Cross-Reference to Related Application

[1001] The application claims priority to and the benefit of U.S Provisional Patent Application Serial No. 62/687,418 entitled,“High-performance Al-Zn-Mg-Zr Base Aluminum Alloys for Welding and Additive Manufacturing,” filed June 20, 2018, the disclosure of which is incorporated herein by reference in its entirety.

Field

[1002] This application relates to a family of Al-Zn-Mg and Al-Zn-Mg-Cu alloys, or 7000- series aluminum alloys, which, when processed by (i) a conventional manufacturing technique (e.g. sheet casting), (ii) a powder metallurgy process, or (iii) an additive manufacturing technique utilizing a melting process, can fabricate a component with ultra-high strength, improved thermal stability and weldability, compared to other commercial 7000-series aluminum alloys.

Background

[1003] 7000-series aluminum alloys are among the highest strength alloys available. Owing to this and other properties, they are often employed in the automotive, aircraft, and aerospace industries. However, 7000-series aluminum alloys are generally recognized by those skilled in the art as being nearly impossible to weld, which limits their use in numerous applications. Accordingly, the ability to provide weldable 7000-series aluminum alloys is highly desirable. Such materials would also be suitable for use in manufacturing processes such as additive manufacturing (i.e., 3D printing), to produce aluminum alloy components and products.

Summary

[1004] The embodiments described herein relate to a 7000-series aluminum-zinc- magnesium-based alloy, comprising one or more additional transition metals or rare earth metals, and optionally copper. The aluminum alloy, which may further include an inoculant (Sn, In, or Sb), can be fabricated into a feedstock (i.e., sheet, wire, powder, etc.) suitable for use in a manufacturing method, which may utilize welding, an additive manufacturing method which utilizes a wire or powder as feedstock, or a powder metallurgy method. In various aspects, the present disclosure provides an aluminum alloy comprising about 4 to about 12% by weight zinc, about 1 to about 4% by weight magnesium, about 0.3 to about 2% by weight zirconium, and aluminum as the remainder. The alloy is found to possess a strength to weight ratio at room temperature, which is at least as great as that of a conventional 7000-series aluminum alloy. As a result of the beneficial properties, the aluminum alloys of the present disclosure can be used in a welding process substantially without resulting liquation-cracking and/or hot-tearing that would result from using the conventional 7000-series aluminum alloy in the welding process. Furthermore, the aluminum alloys of the present disclosure do not comprise any intentionally added scandium.

[1005] The present disclosure also provides a method of producing a weldable aluminum alloy. This method comprises melting recycled or virgin aluminum, while adding aluminum- master alloys or pure elements, at a temperature of about 700°C to about l000°C to form a liquid mixture of constituents, the liquid mixture of constituents comprising about 4 to about 12% by weight zinc, about 1 to about 4% by weight magnesium, about 0.3 to about 2% by weight zirconium or alternatively about 0.3 to about 2% by weight titanium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, yttrium, lanthanum, cerium, praseodymium, neodymium, gadolinium, dysprosium, erbium, or ytterbium, or combinations thereof, optionally up to about 3% by weight copper, and aluminum as the remainder, wherein the liquid mixture of constituents does not comprise any intentionally added scandium. The melted constituents can be casted into an ambient or a chilled casting mold to form a casted ingot, and heat treated at a temperature of about 400°C to about 480°C for a time of about 0.25 hours to about 6 hours to form a solutionized ingot comprising an Al-Zn-Mg solid-solution with a dispersion of Lb structured AbZr nano-scale precipitates. The solutionized ingot can be hot-formed and/or cold-formed into a sheet, a foil, a rod, a wire, an extrusion, or a forging.

[1006] Further methods are directed to the manufacture of a net-shape component, a near- net-shape component, or a component extruded from a billet. These methods comprise subjecting the 7000-series aluminum alloys of the present disclosure to an additive manufacturing process or a powder metallurgy process to manufacture the net-shape component, the near-net-shape component, and in the case of powder metallurgy, a component extruded from a billet. The components can be heat aged at a temperature of about l00°C to about l80°C for a time of about 1 hour to about 48 hours, to achieve a simultaneous dispersion of fine-scale ZmMg precipitates, primary precipitates (e.g., AbZr), and AbZr nano-scale precipitates, resulting in the component having a strength which is at least as great as that of a net-shape component, near-net-shape component, or component extruded from a billet conventionally manufactured from a conventional 7000-series aluminum alloy.

[1007] The disclosed aluminum alloys can also be used to repair or form a protective coating on a component made from an aluminum alloy. This involves subjecting an aluminum alloy powder to a cold spray process, a thermal spray process, a laser-assisted cold spray process, or a laser cladding process to repair or to form a protective coating on, the component. The component made from an aluminum alloy can be heated treated at a temperature of about 400°C to about 480°C for a time of about 0.25 hours to about 6 hours. In some instances, after heat-treating the component, the component made from an aluminum alloy can be heat aged at a temperature of about l00°C to about l80°C for a time of about 1 hour to about 48 hours.

[1008] An advantage of the 7000-series aluminum alloys disclosed herein is their ability to be welded. Accordingly, a method of preparing a welded metallic assembly is provided. This method comprises joining two or more aluminum alloy components with a filler material in a welding process. The filler material joining the components can be a wire or rod fabricated from a 7000-series aluminum alloy. The two or more aluminum alloy components can each be independently selected from the group consisting of Al-Zn-Mg alloys, Al-Zn-Mg-Cu alloys, Al-Zn-Mg-Zr alloys, and Al-Zn-Mg-Cu-Zr alloys. As described, these alloys comprise about 4 to about 12% by weight zinc, about 1 to about 4% by weight magnesium, about 0.3 to about 2% by weight zirconium, and up to about 3% copper when present. Aluminum makes up the remainder of the composition, which is free of intentionally added scandium.

Brief Description of the Drawings

[1009] The drawings contained herein are examples of the microstructures of the metal alloys described herein, and of the material properties which may be achieved by certain embodiments described herein and are not limiting in any way.

[1010] Fig. 1 is a scanning electron micrograph of a melt-spun ribbon of Al-l lZn-2.5Mg- lCu wt.%. Grains are large, spanning the width of the ribbon.

[1011] Fig. 2 is a scanning electron micrograph of a melt-spun ribbon of Al-l lZn-2.5Mg- lCu-l .5Zr wt.%. Grains are highly refined, with multiple grains contained within the ribbon. [1012] Fig. 3 is an optical micrograph of Al-l lZn-2.5Mg-lCu wt.% melt-spun ribbons which have been hot-compacted and extruded, solution heat treated and artificially aged. Grains have grown to be hundreds of micrometers in size.

[1013] Fig. 4 is an optical micrograph of Al-l lZn-2.5Mg-lCu-l .5Zr wt.% melt-spun ribbons which have been hot-compacted and extruded, solution heat treated and artificially aged. The highly refined grain microstructure has been preserved.

[1014] Fig. 5 shows that a conventionally cast Al-l0Zn-3Mg alloy softens during a conventional solutionizing heat treatment at 450°C, whereas the Al-lOZn-3Mg-l .2Zr shows a hardening response during the same solutionizing step due the precipitation of AbZr nano- precipitates.

[1015] Fig. 6 shows that a conventionally cast Al-l0Zn-3Mg alloy experiences grain growth during a conventional solutionizing heat treatment at 450°C whereas the Al-l0Zn-3Mg- (0.6-l .2)Zr exhibits an improved thermal stability and resists grain growth at high temperatures.

[1016] Fig. 7 shows non-limiting examples of additive manufacturing (AM) processes, according to an embodiment.

[1017] Fig. 8 shows a general powder metallurgy process that includes the steps of compaction and sintering or thermal processing, according to an embodiment.

Detailed Description

[1018] Conventional 7000-series alloy metal powders consist primarily of zinc and magnesium, and optionally of copper, with aluminum being the remainder. This combination of alloying elements is what makes up the 7000 series of aluminum alloys. These alloys are strengthened by the formation of Z Mg precipitates, which form in the solid alloy during a post-process aging treatment. Adding copper to the Al-Zn-Mg based system is known to improve the strength of alloy, but it also degrades the corrosion resistance and the ability of the alloy to be welded. The ability to be welded is an essential prerequisite for an alloy to be processed by an additive manufacturing method.

[1019] In a conventional manufacturing process (e.g., sheet casting) which utilizes welding, two solid metal components are placed in contact with one another, and an energy source is used to locally melt the surface of the two components, and the liquid phase of the two components are mixed by convection. Once solidified, the two components are metallurgically joined, and the chemical composition across the weld is often indistinguishable from the base material. In such processes, the energy source may be an electric current, a laser beam, or an electron beam. In certain processes, additional metal is added to the weld by feeding a wire or a rod into the molten weld, the added material is melted by the energy source and is mixed by convection with the liquid phase of the two components. Once solidified, the two components are metallurgically joined, and the chemical composition of the weld often differs from that of the base material. During these processes, the heat input from the energy source can alter the chemistry and microstructure of the base material, resulting in a region of material, separating the weld from the base material, known as the Heat Affected Zone (HAZ). Thus, the weld can be characterized by three distinct zones, including the weld or fusion zone (FZ), the HAZ, and the base material, often with significant differences in microstructure and mechanical properties. Most notably, the microstructure and mechanical properties of the FZ will resemble that of a cast alloy and will often have much lower strength than the base material. The heat input into the weld is enough to coarsen or recrystallize the adjacent grains in the HAZ, diminishing the properties in this region below that of the base material. The base material is unaffected by the weld and maintains the properties of the starting material.

[1020] When conventional 7000-series aluminum alloys are welded, and particularly those bearing copper as an alloying element, grain growth is uninhibited and phase segregation results in liquation cracks forming between solid and liquid phases, and hot cracking results from the unrefined grain structure’s inability to tolerate the extreme internal stresses which develop during the welding process. Thus, 7000-series aluminum alloys, such as AA7050 and AA7075, are generally recognized by those skilled in the art as being impossible to weld.

[1021] Additive manufacturing, commonly referred to as 3D printing, generally describes a method of forming a net-shape, or near-net-shape, component in an additive manner, where material is deposited one layer at a time until the desired three-dimensional shape is achieved, and there is very little wasted material or scrap resulting from these methods. This contrasts with conventional “subtractive manufacturing” where material is removed from a larger preform, e.g., milling, until the final three-dimensional shape is achieved, and there is generally a lot of wasted material and scrap in these methods.

[1022] Additive manufacturing of metals typically utilizes spherical metal alloy powders and uses a focused energy source, such as a laser beam or an electron beam, to fuse the metal powders at specific locations to fabricate a near-net-shape component with high spatial resolution. The spherical metal powders are typically made by gas-atomization or plasma- atomization, which naturally produces spherical powders, or by plasma spherization, which transforms irregular particles into spherical powders. Typically, during these additive manufacturing techniques, the metal powders are fully melted by the energy source and solidify rapidly so that they are fused to the underlying material, which may be a preexisting substrate or a previously deposited layer of the powder material. To achieve a part with desirable relative density, i.e., >99%, multiple layers of deposited material are re-melted, typically more than once, so that there is complete fusion between each layer of deposited material. During these processes, the molten alloy solidifies rapidly, easily exceeding cooling rates of 10 ³ °C/sec and as high as 10 ⁶ °C/sec. This cooling rate greatly exceeds those experienced during conventional casting of molten alloys which are typically on the order of 10° to 10 ² °C/sec. Because of the very high cooling rates inherent to additive manufacturing techniques, they are considered far- from-equilibrium, and conventional alloys, which have been optimized for equilibrium processing, cannot be easily processed by such methods.

[1023] When conventional 7000-series aluminum alloys are processed by additive manufacturing methods, grain growth is uninhibited, and phase segregation results in liquation cracks forming between solid and liquid phases, and hot cracking results from the unrefined grain structure’s inability to tolerate the extreme internal stresses which develop during the additive manufacturing method. Thus, conventional 7000-series aluminum alloys, such as AA7050 and AA7075, are generally recognized by those skilled in the art as being near impossible to additively manufacture. The solution to both challenges is to refine the size of the grains in the solidified material.

[1024] An attempt to address this issue is by the use of nanoparticles. Nanoparticles can be used to coat the surface of the metal alloy powder, which are then incorporated in the molten alloy during additive manufacturing. These nanoparticles blunt dendrite growth, and thus inhibit grain growth, effectively refining the grain size in the fabricated solid, so that liquation cracking and hot tearing are avoided, and a dense, defect-free component can be fabricated from an otherwise difficult-to-process alloy. However, the process by which the metal alloys powders are coated with nanoparticles adds cost and complexity to the production of metal alloy powders for additive manufacturing, and is thus not considered an ideal art for large-scale and economical production of metal alloy powders to be used in an additive manufacturing method. [1025] 7000-series aluminum alloy powder, which requires scandium (Sc) in addition to optional other elements have been prepared and utilized in an additive manufacturing process. See e.g. Lenczowski (US 2017/0233857 Al). However, scandium is known to be very expensive (about ten times as expensive as silver) and its availability is also limited. Thus, using scandium drastically increases the cost of the powdered alloy, thus limiting its usage for mass applications.

[1026] Generally, an improved method is needed which refines the grain size (measured in accordance with ASTM El 12) in a welded or an additively manufactured component fabricated from an aluminum alloy, and specifically a 7000-series aluminum alloy, which has desirable properties. Preferably, this method can be accomplished by an alloy chemistry and would not require a secondary step to incorporate nanoparticles into the weld or additively manufactured component. In addition, this method should avoid the use of expensive scandium as an added metal element.

[1027] Additionally, it is not only desirable for a 7000-series aluminum alloy to be processed by these methods, but to have an alloy which exceeds the performance of an existing alloy. In other words, it may be desirable to adapt a known 7000-series aluminum alloy, such as AA7075, to overcome the challenges associated with welding and additive manufacturing, but it is more desirable to achieve even higher performance from an alloy based on the Al-Zn- Mg or Al-Zn-Mg-Cu systems.

[1028] High-strength conventional 7000-series aluminum alloys are typically known to be unweldable. In contrast, the disclosed alloys are advantageous for, but not limited to, forming ultra-high-strength and weldable aluminum alloys, which can be welded to components having the same alloy compositions, with or without filler material (i.e., weld feed material or weld wire). The filler material can also have the same alloy compositions as the parent materials. Also, the disclosed alloys are especially advantageous for, but not limited to, powder based additive manufacturing techniques, such as laser powder bed fusion, directed energy deposition, laser engineered net shaping, and laser cladding, and wire-based additive manufacturing techniques, such as wire-arc additive manufacturing. It is notoriously difficult to process 7000-series aluminum alloys by these methods because they tend to fail due to liquation-cracking and hot-tearing, stemming from these alloys inability to be welded. The disclosed alloys have been specifically designed to overcome these challenges so that they are easily processed by such methods where rapid melting and solidification are inherent to the processing. Additionally, the disclosed alloys are advantageous for improving the strength as measured in accordance with ASTM E8/E8M and thermal stability (defined specifically as the stability of grain size) of structural components fabricated from conventional 7000-series, either in powder or wrought product form, because the disclosed alloys form a secondary precipitation-strengthening phase at elevated temperatures which conventional alloys do not. This new phase is responsible for an increase in strength and enables the alloy to resist recrystallization at high temperatures. Lastly, the disclosed alloys are advantageous for conventional powder metallurgy techniques, such as hot isostatic pressing, powder molding, and extrusion. During these techniques, the disclosed alloy again precipitates a non- conventional strengthening phase at elevated temperatures (for example, AbZr), which increases the strength of the alloy and improves thermal stability by resisting recrystallization. These non-conventional precipitates are in addition to the conventional precipitates which strengthen 7000-series aluminum alloys (for example, ZmMg) Thus, the disclosed alloys are, for example, advantageous for improving the performance of structural components in aerospace and automotive applications, in sporting and leisure equipment, and in consumer goods.

Definitions

[1029] As used herein,“conventional 7000-series aluminum alloy” refers to an aluminum alloy where zinc (Zn) is the primary alloying element and magnesium is present in smaller amounts. Other elements such as copper, silicon, and iron may also be added in small quantities. Conventional 7000-series aluminum alloys are characterized as being heat- treatable, high-strength materials. Examples of commonly known 7000-series aluminum alloys include AA7070 and AA7075.

[1030] As used herein,“grain growth” refers to an increase in the size of grains in solid aluminum.

[1031] As used herein,“liquation cracking” or“hot cracking” refers to the formation of shrinkage cracks during the solidification of the weld metal.

[1032] As used herein,“solid solution” refers to a solid mixture containing a minor component uniformly distributed within the crystal lattice of the major component. This is distinguished from a mechanical mixture of two or more solids that have a total or partial miscibility gap in solid state. [1033] As used herein,“component” refers to a net-shape or near-net-shape metal structure fabricated from an aluminum alloy or aluminum alloy powder.

[1034] As used herein,“additive manufacturing” (AM) refers to any process which results in a three-dimensional object and includes a step of sequentially forming the shape of the object one layer at a time. For example, AM processes include three-dimensional printing (3DP) processes, laser-net-shape manufacturing, direct metal laser sintering (DMLS), direct metal laser melting (DMLM), plasma transferred arc, freeform fabrication, etc. A non-limiting particular type of AM process uses an energy beam, for example, an electron beam or electromagnetic radiation such as a laser beam, to sinter or melt a powder material. AM processes can employ metal powder materials or wire as a raw material.

[1035] The embodiments described herein relate to Al-Zn-Mg-based aluminum alloys, which have been alloyed further with transition metal or rare earth metal elements, and which may include copper and/or an inoculant (Sn, In, or Sb), so that the alloys have high strength, improved thermal stability, and superior weldability. Accordingly, in some embodiments, the aluminum alloys of the present disclosure are heat-treatable aluminum alloys.

Alloy Compositions

[1036] In some embodiments of the present disclosure, an aluminum alloy is provided that comprises about 4 to about 12% by weight zinc, about 1 to about 4% by weight magnesium, about 0.3 to about 2% by weight of a transition metal element or a rare earth element; and aluminum as the remainder, wherein the alloy does not comprise any intentionally added scandium. In some embodiments, the alloy possesses a strength to weight ratio at room temperature which is at least as great as that of a conventional 7000-series aluminum alloy. In some embodiments, the alloy can be used in a welding process substantially without resulting liquation-cracking and hot-tearing that would result from using the conventional 7000-series aluminum alloy in the welding process. In some embodiments, the transition metal or rare earth metal is selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Y, La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. In some embodiments, the transition metal is selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, and Y. In some embodiments, the transition metal is selected from the group consisting of Ti, Hf, V, Nb, Ta, Cr, Mo, W, Mn, and Y. In some embodiments, the transition metal element in the disclosed aluminum alloy is selected from the group consisting of Ti, Zr, Hf, and V. In some embodiments, the rare earth metal is selected from the group consisting of La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. In some embodiments, the rare earth metal is selected from the group consisting of La, Ce, Pr, Nd, Gd, Dy, Er, and Yb.

[1037] In some embodiments of the present disclosure, an aluminum alloy is provided that consists essentially of about 4 to about 12% by weight zinc, about 1 to about 4% by weight magnesium, about 0.3 to about 2% by weight of a transition metal element or a rare earth element; and aluminum as the remainder, wherein the alloy does not comprise any intentionally added scandium. In some embodiments, the alloy possesses a strength to weight ratio at room temperature which is at least as great as that of a conventional 7000-series aluminum alloy. In some embodiments, the alloy can be used in a welding process substantially without resulting liquation-cracking and hot-tearing that would result from using the conventional 7000-series aluminum alloy in the welding process. In some embodiments, the transition metal or rare earth metal is selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Y, La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. In some embodiments, the aluminum alloy comprises about 0.3 to about 2% of a transition metal element. In some embodiments, the transition metal is selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, and Y. In some embodiments, the transition metal is selected from the group consisting of Ti, Hf, V, Nb, Ta, Cr, Mo, W, Mn, and Y. In some embodiments, the transition metal element in the disclosed aluminum alloy is selected from the group consisting of Ti, Zr, Hf, and V. In some embodiments, the rare earth metal is selected from the group consisting of La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. In some embodiments, the rare earth metal is selected from the group consisting of La, Ce, Pr, Nd, Gd, Dy, Er, and Yb.

[1038] In some embodiments of the present disclosure, an aluminum alloy that consists essentially of about 4 to about 12% by weight zinc, about 1 to about 4% by weight magnesium, about 0.3 to about 2% by weight of a transition metal element or a rare earth element; and aluminum as the remainder, wherein the alloy does not comprise any intentionally added scandium further comprises metallic or metalloid impurities. Impurity in this context refers to a metallic or metalloid additive that does not affect the other intended strengthening mechanisms or significantly degrade the material properties of the aluminum alloy. In some embodiments, the impurities in the disclosed aluminum alloy are silicon and/or iron. In some embodiments, the silicon and/or iron impurities in the disclosed aluminum alloys are present in an amount that does not exceed about 0.5% by weight. In some embodiments, the silicon and/or iron impurities in the disclosed aluminum alloys are present in an amount that does not exceed about 0.3% by weight. In some embodiments, the silicon and/or iron impurities are present in the disclosed aluminum alloys in an amount that does not exceed about 0.1%. Without being bound by any particular theory, it was found that a high concentration (i.e., a concentration exceeding about 0.5% by weight) of impurity or combination of impurities (i.e., silicon and/or iron) will form detrimental intermetallic phases in the aluminum matrix that negatively affect the mechanical properties of the aluminum alloys disclosed herein.

[1039] In some embodiments of the present disclosure, an aluminum alloy is provided that comprises about 4 to about 12% by weight zinc, about 1 to about 4% by weight magnesium, about 0.3 to about 2% by weight of a transition metal element; and aluminum as the remainder, wherein the alloy does not comprise any intentionally added scandium. In some embodiments, the alloy possesses a strength to weight ratio at room temperature which is at least as great as that of a conventional 7000-series aluminum alloy. In some embodiments, the alloy can be used in a welding process substantially without resulting liquation-cracking and hot-tearing that would result from using the conventional 7000-series aluminum alloy in the welding process. In some embodiments, the transition metal is selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, and Y. In some embodiments, the transition metal is selected from the group consisting of Ti, Hf, V, Nb, Ta, Cr, Mo, W, Mn, and Y. In some embodiments, the transition metal element in the disclosed aluminum alloy is selected from the group consisting of Ti, Zr, Hf, and V. In some embodiments, the transition metal is Zr.

[1040] In some embodiments of the present disclosure, an aluminum alloy is provided that comprises about 4 to about 12% by weight zinc, about 1 to about 4% by weight magnesium, about 0.3 to about 2% by weight of a rare earth element; and aluminum as the remainder, wherein the alloy does not comprise any intentionally added scandium. In some embodiments, the alloy possesses a strength to weight ratio at room temperature which is at least as great as that of a conventional 7000-series aluminum alloy. In some embodiments, the alloy can be used in a welding process substantially without resulting liquation-cracking and hot-tearing that would result from using the conventional 7000-series aluminum alloy in the welding process. In some embodiments, the rare earth metal is selected from the group consisting of La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. In some embodiments, the rare earth metal is selected from the group consisting of La, Ce, Pr, Nd, Gd, Dy, Er, and Yb.

[1041] In some embodiments, the amount of zinc in the disclosed alloy is from about 4 to about 12% by weight zinc, e.g., about 4%, about 4.5%, about 5%, about 5.5%, about 6%, about 6.5%, about 7%, about 7.5%, about 8%, about 8.5%, about 9%, about 9.5%, about 10%, about 10.5%, about 11%, about 11.5%, or about 12%, including all ranges and values therebetween. In some embodiments, the alloys of the present disclosure comprise about 5 to about 12% by weight zinc, about 6 to about 12% by weight zinc, about 7 to about 12%, about 8 to about 12%, about 9 to about 12%, about 10 to about 12%, about 5 to about 11%, about 6 to about 11%, about 7 to about 11%, about 8 to about 11%, about 4 to about 10%, about 5 to about 10%, about 6 to about 10%, about 7 to about 10%, about 8 to about 10%, about 4 to about 9%, about 5 to about 9%, about 6 to about 9%, about 7 to about 9%, about 4 to about 8%, about 5 to about 8%, about 6 to about 8%, about 4 to about 7%, about 5 to about 7%, about 4 to about 6%, including all ranges and values therebetween. In some embodiments, the amount of zinc in the disclosed alloy is from about 7 to about 12% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is from about 7 to about 11% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is from about 7 to about 10% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is from about 7 to about 9% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is from about 8 to about 12% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is from about 8 to about 11% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is from about 8 to about 10% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is about 5 to about 11% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is about 5 to about 10% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is about 5 to about 9% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is about 5 to about 8% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is about 5 to about 7% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is about 6 to about 12% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is about 6 to about 1 1% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is about 6 to about 10% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is about 6 to about 9% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is about 6 to about 8% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is about 5 to about 10% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is about 5 to about 9% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is about 5 to about 8% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is about 10% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is about 11% by weight zinc. In some embodiments, the amount of zinc in the disclosed alloy is about 12% by weight zinc. In some embodiments,

[1042] In some embodiments, the amount of magnesium in the disclosed alloy is from about 1 to about 4% by weight magnesium, e.g., about 1%, about 1.25%, about 1.5%, about 1.75%, about 2%, about 2.25%, about 2.5%, about 2.75%, about 3%, about 3.25%, about 3.5%, about 3.75%, or about 4%, including all ranges and values therebetween. In some embodiments, the amount of magnesium in the disclosed alloy is from about 1 to about 3% by weight magnesium. In some embodiments, the amount of magnesium in the disclosed alloy is from about 2 to about 4% by weight magnesium In some embodiments, the amount of magnesium in the disclosed alloy is about 1.5% by weight magnesium. In some embodiments, the amount of magnesium in the disclosed alloy is about 2% by weight magnesium. In some embodiments, the amount of magnesium in the disclosed alloy is about 2.5% by weight magnesium. In some embodiments, the amount of magnesium in the disclosed alloy is about 3% by weight magnesium. In some embodiments, the amount of magnesium in the disclosed alloy is about 3.5% by weight magnesium. In some embodiments, the amount of magnesium in the disclosed alloy is about 4% by weight magnesium.

[1043] In some embodiments, the transition metal element or rare earth metal element in the disclosed aluminum alloy is selected from the group consisting of titanium (Ti), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), chromium (Cr), molybdenum (Mo), tungsten (W), manganese (Mn), yttrium (Y), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu), or combinations thereof. In some embodiments, the amount of transitional metal elements or rare earth elements present in the disclosed alloy is from about 0.3 to about 2% by weight of the metal, e.g., about 0.3%, about 0.4%, about 0.5%, about 0.6%, about 0.7%, about 0.8%, about 0.9%, about 1.0%, about 1.1%, about 1.2%, about 1.3%, about 1.4%, about 1.5%, about 1.6%, about 1.7%, about 1.8%, about 1.9%, or about 2% by weight of the metal, including all ranges and values therebetween. In some embodiments, the amount of transitional metal elements or rare earth elements present in the disclosed alloy is from about 0.3 to about 1% by weight of the metal. In some embodiments, the amount of transitional metal elements or rare earth elements present in the disclosed alloy is from about 0.3 to about 0.7% by weight of the metal. In some embodiments, the amount of transitional metal elements or rare earth elements present in the disclosed alloy is from about 1 to about 2% by weight of the metal. In some embodiments, the amount of transitional metal elements or rare earth elements present in the disclosed alloy is from about 1 to about 1.5% by weight of the metal. In some embodiments, the amount of transitional metal elements or rare earth elements present in the disclosed alloy is from about 1.25 to about 1.75% by weight of the metal. In some embodiments, the amount of transitional metal elements or rare earth elements present in the disclosed alloy is from about 1.4 to about 1.6% by weight of the metal. In some embodiments, the amount of transitional metal elements or rare earth elements present in the disclosed alloy is from about 1.5 to about 2% by weight of the metal. In some embodiments, the amount of transitional metal elements or rare earth elements present in the disclosed alloy is from about 0.1 to about 1% by weight of the metal, e.g., about 0.1%, about 0.15%, about 0.2%, about 0.25%, about 0.3%, about 0.35%, about 0.4%, about 0.45%, about 0.5%, about 0.55%, about 0.6%, about 0.65%, about 0.7%, about 0.75%, about 0.8%, about 0.85%, about 0.9%, about 0.95%, or about 1% by weight of the metal, including all ranges and values therebetween. In some embodiments, the amount of transitional metal elements or rare earth elements present in the disclosed alloy is from about 0.1 to about 0.5% by weight of the metal. In some embodiments, the amount of transitional metal elements or rare earth elements present in the disclosed alloy is from about 0.6 to about 1% by weight of the metal. In some embodiments, the amount of transitional metal elements or rare earth elements present in the disclosed aluminum alloy is greater than about 0.5% by weight of the metal. In some embodiments, the amount of transitional metal elements or rare earth elements present in the disclosed aluminum alloy is about 1.0% by weight of the metal. In some embodiments, the amount of transitional metal elements or rare earth elements present in the disclosed aluminum alloy is about 1.5% by weight of the metal. In some embodiments, the amount of transitional metal elements or rare earth elements present in the disclosed aluminum alloy is about 2.0% by weight of the metal.

[1044] In some embodiments, the rare earth metal is selected from the group consisting of La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. In some embodiments, the rare earth metal is selected from the group consisting of La, Ce, Pr, Nd, Gd, Dy, Er, and Yb. In some embodiments, the amount of rare earth metal present in the disclosed alloy is from about 0.3 to about 2% by weight, e.g., about 0.3%, about 0.4%, about 0.5%, about 0.6%, about 0.7%, about 0.8%, about 0.9%, about 1.0%, about 1.1%, about 1.2%, about 1.3%, about 1.4%, about 1.5%, about 1.6%, about 1.7%, about 1.8%, about 1.9%, or about 2% by weight of the rare earth metal, including all ranges and values therebetween. In some embodiments, the amount of the rare earth metal present in the disclosed alloy is from about 1 to about 2% by weight, including all ranges and values therebetween. In some embodiments, the amount of the rare earth elements present in the disclosed alloy is from about 0.3 to about 1% by weight of the metal. In some embodiments, the amount of the rare earth elements present in the disclosed alloy is from about 0.3 to about 0.7% by weight of the metal. In some embodiments, the amount of the rare earth elements present in the disclosed alloy is from about 1 to about 2% by weight of the metal. In some embodiments, the amount of the rare earth elements present in the disclosed alloy is from about 1 to about 1.5% by weight of the metal. In some embodiments, the amount of the rare earth elements present in the disclosed alloy is from about 1.25 to about 1.75% by weight of the metal. In some embodiments, the amount of the rare earth elements present in the disclosed alloy is from about 1.4 to about 1.6% by weight of the metal. In some embodiments, the amount of the rare earth elements present in the disclosed alloy is from about 1.5 to about 2% by weight of the metal. In some embodiments, the amount of the rare earth metal present in the disclosed alloy is about 1.0% by weight. In some embodiments, the amount of the rare earth metal present in the disclosed alloy is about 1.5% by weight. In some embodiments, the amount of the rare earth metal present in the disclosed alloy is about 2.0% by weight.

[1045] In some embodiments, the transition metal element in the disclosed aluminum alloy is selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, and Y. In some embodiments, the transition metal element in the disclosed aluminum alloy is selected from the group consisting of Ti, Hf, V, Nb, Ta, Cr, Mo, W, Mn, and Y. In some embodiments, the transition metal element in the disclosed aluminum alloy is selected from the group consisting of Ti, Hf, and V. In some embodiments, the amount of transition metal present in the disclosed alloy is from about 0.3 to about 2% by weight, e.g., about 0.3%, about 0.4%, about 0.5%, about 0.6%, about 0.7%, about 0.8%, about 0.9%, about 1.0%, about 1.1%, about 1.2%, about 1.3%, about 1.4%, about 1.5%, about 1.6%, about 1.7%, about 1.8%, about 1.9%, or about 2% by weight of the transition metal, including all ranges and values therebetween. In some embodiments, the amount of transition metal present in the disclosed alloy is from about 1 to about 2% by weight, including all ranges and values therebetween. In some embodiments, the amount of transitional metal elements present in the disclosed alloy is from about 0.3 to about 1% by weight of the metal. In some embodiments, the amount of transitional metal elements in the disclosed alloy is from about 0.3 to about 0.7% by weight of the metal. In some embodiments, the amount of transitional metal elements in the disclosed alloy is from about 1 to about 2% by weight of the metal. In some embodiments, the amount of transitional metal elements in the disclosed alloy is from about 1 to about 1.5% by weight of the metal. In some embodiments, the amount of transitional metal elements in the disclosed alloy is from about 1.25 to about 1.75% by weight of the metal. In some embodiments, the amount of transitional metal elements in the disclosed alloy is from about 1.4 to about 1.6% by weight of the metal. In some embodiments, the amount of transitional metal elements in the disclosed alloy is from about 1.5 to about 2% by weight of the metal. In some embodiments, the amount of the transition metal present in the disclosed alloy is about 1.0% by weight. In some embodiments, the amount of the transition metal present in the disclosed alloy is about 1.5% by weight. In some embodiments, the amount of the transition metal present in the disclosed alloy is about 2.0% by weight.

[1046] In some embodiments, the transition metal element in the disclosed aluminum alloy is zirconium (Zr). In some embodiments, the amount of zirconium present in the disclosed alloy is from about 0.3 to about 2% by weight zirconium, e.g., about 0.3%, about 0.4%, about 0.5%, about 0.6%, about 0.7%, about 0.8%, about 0.9%, about 1.0%, about 1.1%, about 1.2%, about 1.3%, about 1.4%, about 1.5%, about 1.6%, about 1.7%, about 1.8%, about 1.9%, or about 2% by weight Zr, including all ranges and values therebetween. In some embodiments, the amount of zirconium present in the disclosed alloy is from about 1 to about 2% by weight zirconium, including all ranges and values therebetween. In some embodiments, the amount of zirconium present in the disclosed alloy is from about 0.3 to about 1% by weight of zirconium. In some embodiments, the amount of zirconium present in the disclosed alloy is from about 0.3 to about 0.7% by weight of zirconium. In some embodiments, the amount of zirconium present in the disclosed alloy is from about 1 to about 2% by weight of zirconium. In some embodiments, the amount of zirconium present in the disclosed alloy is from about 1 to about 1.5% by weight of zirconium. In some embodiments, the amount of zirconium present in the disclosed alloy is from about 1.25 to about 1.75% by weight of zirconium. In some embodiments, the amount of zirconium present in the disclosed alloy is from about 1.4 to about 1.6% by weight of zirconium. In some embodiments, the amount of zirconium present in the disclosed alloy is from about 1.5 to about 2% by weight of zirconium. In some embodiments, the amount of zirconium present in the disclosed alloy is about 1.0% by weight Zr. In some embodiments, the amount of zirconium present in the disclosed alloy is about 1.5% by weight Zr. In some embodiments, the amount of zirconium present in the disclosed alloy is about 2.0% by weight Zr. [1047] In some embodiments, the alloy is differentiated from the conventional 7000-series alloys by the further addition of a transition metal element, a rare earth element, or a lanthanide, excluding Sc. In some embodiments, the total addition of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, La, Ce, Pr, Nd, Gd, Dy, Er, Tm, Yb, Lu or combinations thereof to the alloy is from about 0.05 to about 0.8 atomic percent (at.%). In some embodiments, the total addition of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, La, Ce, Pr, Nd, Gd, Dy, Er, Tm, Yb, Lu or combinations thereof to the alloy is from about 0.3 to about 0.5 at.%. As shown in Table 1, these concentrations greatly exceed the maximum equilibrium solubility limit of these elements in solid aluminum, which is less than about 0.1 at.% for most of these elements.

Table 1

• Knipling, Keith E., David C. Dunand, and David N. Seidman. "Criteria for developing castable, creep-resistant aluminum-based alloys-A review." Zeitschrift fur Metallkunde 97, no. 3 (2006): 246-265.

[1048] Accordingly, in some embodiments, the present disclosure provides an aluminum alloy comprising: about 4 to about 12% by weight zinc; about 1 to about 4% by weight magnesium; about 0.3 to about 2% by weight zirconium; and aluminum as the remainder, wherein the alloy does not comprise any intentionally added scandium (Sc). In some embodiments, the alloy possesses a strength to weight ratio at room temperature which is at least as great as that of a conventional 7000-series aluminum alloy. In some embodiments, the alloy can be used in a welding process substantially without resulting in liquation-cracking and hot-tearing that would result from using the conventional 7000-series aluminum alloy in the welding process.

[1049] In some embodiments, the present disclosure provides an aluminum alloy comprising: about 4 to about 12% by weight zinc; about 1 to about 4% by weight magnesium; about 0.3 to about 2% by weight of titanium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium or lutetium, or a combination thereof; and aluminum as the remainder, wherein the alloy does not comprise any intentionally added scandium (Sc). In some embodiments, the alloy possesses a strength to weight ratio at room temperature which is at least as great as that of a conventional 7000-series aluminum alloy. In some embodiments, the alloy can be used in a welding process substantially without resulting in liquation-cracking and hot-tearing that would result from using the conventional 7000-series aluminum alloy in the welding process.

[1050] In some embodiments, an aluminum alloy comprising about 4 to about 12% by weight zinc; about 1 to about 4% by weight magnesium; about 0.3 to about 2% by weight zirconium, further comprise about 0.1 to about 1% by weight of titanium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium or lutetium, or combinations thereof; and aluminum as the remainder, wherein the alloy possesses a strength to weight ratio at room temperature which is at least as great as that of a conventional 7000-series aluminum alloy; wherein the alloy can be used in a welding process substantially without resulting liquation-cracking and hot-tearing that would result from using the conventional 7000-series aluminum alloy in the welding process; and wherein the alloy does not comprise any intentionally added scandium. In some embodiments, the amount of titanium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium or lutetium, or combinations thereof is about 0.1%, about 0.15%, about 0.2%, about 0.25%, about 0.3%, about 0.35%, about 0.4%, about 0.45%, about 0.5%, about 0.55%, about 0.6%, about 0.65%, about 0.7%, about 0.75%, about 0.8%, about 0.85%, about 0.9%, about 0.95%, or about 1% by weight of the metal, including all ranges and values therebetween.

[1051] As described herein, the disclosed alloys are free of scandium. In some embodiments, no scandium is intentionally added to the aluminum alloys disclosed herein. Consequently, in some embodiments, the amount of scandium in the aluminum alloys of the present disclosure is less than about 0.05%, less than about 0.04%, less than about 0.03%, less than about 0.02%, less than about 0.01%, less than about 0.005%, or less than about 0.001% by weight of the total composition. In some embodiments, the amount of scandium in the aluminum alloy is less than about 0.1% by weight of the alloy composition. In some embodiments, the amount of scandium in the aluminum alloy is less than about 0.05% by weight of the alloy composition. In some embodiments, the amount of scandium in the aluminum alloy is less than about 0.02% by weight of the alloy composition. In some embodiments, the amount of scandium in the aluminum alloy is less than about 0.01% by weight of the alloy composition.

[1052] In some embodiments, the aluminum alloys of the present disclosure comprise primary precipitates, e.g., AbZr, which are believe to further strengthen the alloy. In some embodiments, the primary precipitates have an average diameter of from about 0.05 to about 1.5 pm, e.g., about 0.05 pm, about 0.1 pm, about 0.15 pm, about 0.2 pm, about 0.25 pm, about 0.3 pm, about 0.35 pm, about 0.4 pm, about 0.45 pm, about 0.5 pm, about 0.55 pm, about 0.6 pm, about 0.65 pm, about 0.7 pm, about 0.75 pm, about 0.8 pm, about 0.85 pm, about 0.9 pm, about 0.95 pm, about 1.00 pm, about 1.05 pm, about 1.1 pm, about 1.15 pm, about 1.2 pm, about 1.25 pm, about 1.3 pm, about 1.35 pm, about 1.4 pm, about 1.45 pm, or about 1.5 pm, including all ranges and values therebetween. In some embodiments, the primary precipitates have an average diameter ranging from about 0.1 to about 1.5 pm. In some embodiments, the primary precipitates are Al-X primary precipitates. In some embodiments, X is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Y, La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu. In some embodiments, the primary precipitates are AhZr In some embodiments, when multiple transition metals or rare earth metals are present in the aluminum alloy, the Al-X primary precipitates are AI-X1-X2, AI-X1-X2-X3, etc. primary precipitates, wherein Xi, X2, and X3 and so forth each represent a different transition metal or rare earth metal.

[1053] In some embodiments, the primary precipitates are nano-scale precipitates having an average diameter of from about 1 to about 100 nm, e.g., about 1 nm, about 2 nm, about 4 nm, about 6 nm, about 8 nm, about 10 nm, about 12 nm, about 14 nm, about 16 nm, about 18 nm, about 20 nm, about 22 nm, about 24 nm, about 26 nm, about 28 nm, about 30 nm, about 32 nm, about 34 nm, about 36 nm, about 38 nm, about 40 nm, about 42 nm, about 44 nm, about 46 nm, about 48 nm, about 50 nm, about 52 nm, about 54 nm, about 56 nm, about 58 nm, about 60 nm, about 62 nm, about 64 nm, about 66 nm, about 68 nm, about 70 nm, about 72 nm, about 74 nm, about 76 nm, about 78 nm, about 80 nm, about 82 nm, about 84 nm, about 86 nm, about 88 nm, about 90 nm, about 92 nm, about 94 nm, about 96 nm, about 98 nm, or about 100 nm, including all ranges and values therebetween. In some embodiments, the nano-scale precipitates have an average diameter of from about 3 to about 50 nm. In some embodiments, the nano-scale precipitates have an average diameter of from about 3 to about 20 nm. In some embodiments, the nano-scale precipitates are Al-X nano-scale precipitates. In some embodiments, X is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Y, La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu. In some embodiments, the nano-scale precipitates are AbZr. In some embodiments, when multiple transition metals or rare earth metals are present in the aluminum alloy, the Al-X nano-scale precipitates are AI-X1-X2, AI-X1-X2-X3, etc. nano-scale precipitates, wherein Xi, X2, and X3 and so forth each represent a different transition metal or rare earth metal.

[1054] In some embodiments, the nano-scale precipitates Al-X (or AI-X1-X2, AI-X1-X2-X3, etc.) with an Lb crystal structure have an average diameter ranging from about 1 to about 100 nm, e.g., about 1 nm, about 2 nm, about 4 nm, about 6 nm, about 8 nm, about 10 nm, about 12 nm, about 14 nm, about 16 nm, about 18 nm, about 20 nm, about 22 nm, about 24 nm, about 26 nm, about 28 nm, about 30 nm, about 32 nm, about 34 nm, about 36 nm, about 38 nm, about 40 nm, about 42 nm, about 44 nm, about 46 nm, about 48 nm, about 50 nm, about 52 nm, about 54 nm, about 56 nm, about 58 nm, about 60 nm, about 62 nm, about 64 nm, about 66 nm, about 68 nm, about 70 nm, about 72 nm, about 74 nm, about 76 nm, about 78 nm, about 80 nm, about 82 nm, about 84 nm, about 86 nm, about 88 nm, about 90 nm, about 92 nm, about 94 nm, about 96 nm, about 98 nm, or about 100 nm, including all ranges and values therebetween. In some embodiments, the nano-scale precipitates with an Lb crystal structure have an average diameter ranging from about 3 to about 50 nm. In some embodiments, the nano-scale precipitates with an Lb crystal structure have an average diameter ranging from about 3 to about 20 nm. Without being bound by any particular theory, it is believed that the formation of these nano-scale precipitates provides an increase in strength over what could be expected from a conventional 7000-series alloy. In some embodiments, X is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Y, La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu. In some embodiments, the nano-scale precipitates with an Lb crystal structure are AbZn nano-scale precipitates.

[1055] In some embodiments, the aluminum alloys of the present disclosure comprise an aluminum matrix with a simultaneous dispersion of Al-X primary precipitates and ZmMg precipitates. In some embodiments, the simultaneous dispersion further comprises nano-scale precipitates Al-X. In some embodiments, X is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Y, La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu.

[1056] The addition of the previously stated elements Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Y, La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu (X) is expected to form thermally stable aluminide intermetallic phases in the metal alloy, i.e. Al-X, and in the case of multiple elements being added, a mixed aluminide phase will form, i.e. Al-(Xi, X2, X3, etc.). Without being bound by any particular theory, it is believed the purpose of these additional elements and the resulting intermetallic phases is three-fold:

1. These solid intermetallic phases will precipitate from the molten alloy to form primary precipitates, which are about 0.1 to lOs of micrometers, and which are preferably 0.1 to 1.5 pm in size, and which provide nucleation sites for fcc-Al grains upon solidification, so that the solidified alloy has a refined grain size. In some embodiments, the primary precipitates are about 0.1 to about 1.5 pm. This overcomes some of the generic challenges associated with additive manufacturing.

2. During a post-process heat treatment, these elements will form nano-scale, aluminide precipitates in the solid alloy, which are about 1 to about 100 nm in size or about 3 to about 20 nm. These precipitates provide an increase in strength over what could be expected from a conventional 7000-series alloy. Additionally, these aluminide precipitates generally do not interact with the zinc and magnesium which are present in the alloy, and which form fine-scale, ZmMg precipitates in the solid alloy, which are responsible for the strengthening effect in a conventional 7000-series alloy, so that after the heat treatment, the alloy may be heat treated in a conventional manner to gain the strength which could be expected from a conventional 7000-series alloy.

3. Both the fine-scale, primary precipitates and the nano-scale aluminide precipitates have excellent thermal stability due to the sluggish diffusivity of these elements in solid aluminum. These precipitates improve the thermal stability of the alloy by providing a barrier to recrystallization. [1057] In some embodiments, the disclosed alloys form a non-conventional strengthening phase (e.g., an intermetallic phase such as AhZr) at elevated temperatures that is not present in conventional 7000-series alloys. These non-conventional precipitates are in addition to the conventional precipitates which strengthen 7000-series aluminum alloys (for example, ZmMg) Without being bound by any particular theory, this new phase is responsible for an increase in strength and improves thermal stability by resisting recrystallization.

[1058] In some embodiments, copper is further added to the 7000-series aluminum alloys of the present disclosure. In some embodiments, the amount of copper in the disclosed aluminum alloy is up to about 3% by weight copper. In some embodiments, the amount of copper in the disclosed aluminum alloy is from about 1 to about 4% by weight copper, e.g., about 1%, about 1.25%, about 1.5%, about 1.75%, about 2%, about 2.25%, about 2.5%, about 2.75%, about 3%, about 3.25%, about 3.5%, about 3.75%, or about 4%, including all ranges and values therebetween. In some embodiments, the amount of copper in the disclosed aluminum alloy is from about 0 to about 3% by weight copper. In some embodiments, aluminum alloy of the present disclosure comprises no more than 3% by weight copper. In some embodiments, aluminum alloy of the present disclosure comprises no more than 2% by weight copper. In some embodiments, aluminum alloy of the present disclosure comprises no more than 1% by weight copper. In some embodiments, aluminum alloy of the present disclosure comprises about 1% by weight copper.

[1059] In some embodiments, the aluminum alloy of the present disclosure further comprises Sn, In, or Sb, ranging from about 0.001 to about 0.1 at.%, e.g., about 0.001%, about 0.005%, about 0.010%, about 0.015%, about 0.02%, about 0.025, about 0.030%, about 0.035%, about 0.040%, about 0.045%, about 0.050%, about 0.055%, about 0.060%, about 0.065%, about 0.070%, about 0.075%, about 0.080%, about 0.085%, about 0.090%, or about 0.10%, about 0.15%, including all ranges and values therebetween. Without being bound by any particular theory, these minor additions are found to accelerate precipitation kinetics of transition metals.

[1060] In some embodiments, the aluminum alloys of the present disclosure further comprise one or more of silicon (Si) and iron (Fe) impurities. In some embodiments, the silicon and/or iron impurities in the disclosed aluminum alloys are present in an amount that does not exceed about 1% by weight, about 0.9% by weight, about 0.8% by weight, about 0.7% by weight, about 0.6% by weight, about 0.5% by weight, about 0.4% by weight, about 0.3% by weight, about 0.2% by weight, or about 0.1% by weight, individually or in combination, including all ranges and values therebetween. In some embodiments, the silicon and/or iron impurities in the disclosed aluminum alloys are present in an amount that does not exceed about 0.5% by weight. In some embodiments, the silicon and/or iron impurities in the disclosed aluminum alloys are present in an amount that does not exceed about 0.3% by weight. In some embodiments, the silicon and/or iron impurities are present in the disclosed aluminum alloys in an amount that does not exceed about 0.1%. Without being bound by any particular theory, it was found that a high concentration (i.e., a concentration exceeding about 0.5% by weight) of impurity or combination of impurities (i.e., silicon and/or iron) will form detrimental intermetallic phases in the aluminum matrix that negatively affect mechanical properties of the aluminum alloys disclosed herein.

[1061] In some embodiments, the aluminum alloys of the present disclosure comprise 4 to 12% by weight zinc, 1 to 4% by weight magnesium, optional copper up to about 3% by weight, 0.3 to 2% by weight zirconium, and aluminum as the remainder. In some embodiments, the alloy does not comprise any intentionally added scandium. Accordingly, the amount of scandium is less than about 0.05% or less than about 0.02% by weight.

[1062] In some embodiments, the aluminum alloys of the present disclosure comprise 7 to 12% by weight zinc, 2 to 4% by weight magnesium, optional copper up to about 3% by weight, 0.3 to 2% by weight zirconium, and aluminum as the remainder. In some embodiments, the alloy does not comprise any intentionally added scandium. Accordingly, the amount of scandium is less than about 0.05% or less than about 0.02% by weight.

[1063] In some embodiments, the aluminum alloys of the present disclosure comprise 5 to 7% by weight zinc, 1 to 4% by weight magnesium, optional copper up to about 3% by weight, 0.3 to 2% by weight zirconium, and aluminum as the remainder. In some embodiments, the alloy does not comprise any intentionally added scandium. Accordingly, the amount of scandium is less than about 0.05% or less than about 0.02% by weight.

[1064] In some embodiments, the alloys of the present disclosure comprise about 4 to about 12% by weight zinc, 1 to 4% by weight magnesium, optional copper up to about 3% by weight, 0.3 to 2% by weight zirconium, impurities of manganese, chromium, silicon, and iron that do not exceed about 0.5% by weight, and aluminum as the remainder. In some embodiments, the alloy does not comprise any intentionally added scandium. Accordingly, the amount of scandium is less than about 0.05% or less than about 0.02% by weight. [1065] In some embodiments, the alloys of the present disclosure comprise about 7 to about 12% by weight zinc, 1 to 4% by weight magnesium, optional copper up to about 3% by weight, 0.3 to 2% by weight zirconium, impurities of manganese, chromium, silicon, and iron that do not exceed about 0.5% by weight, and aluminum as the remainder. In some embodiments, the alloy does not comprise any intentionally added scandium. Accordingly, the amount of scandium is less than about 0.05% or less than about 0.02% by weight.

[1066] In some embodiments, the alloys of the present disclosure comprise about 5 to about 7% by weight zinc, 1 to 4% by weight magnesium, optional copper up to about 3% by weight, 0.3 to 2% by weight zirconium, impurities of manganese, chromium, silicon, and iron that do not exceed about 0.5% by weight, and aluminum as the remainder. In some embodiments, the alloy does not comprise any intentionally added scandium. Accordingly, the amount of scandium is less than about 0.05% or less than about 0.02% by weight.

[1067] In some embodiments, the aluminum alloys of the present disclosure comprise about 4 to about 12% by weight zinc, 1 to 4% by weight magnesium, optional copper up to about 3% by weight, 0.3 to 2% by weight titanium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium or lutetium, or combinations thereof, impurities of manganese, chromium, silicon, and iron that do not exceed about 0.5% by weight, and aluminum as the remainder. In some embodiments, the alloy does not comprise any intentionally added scandium. Accordingly, the amount of scandium is less than about 0.05% or less than about 0.02% by weight.

[1068] In some embodiments, the aluminum alloys of the present disclosure comprise about 7 to about 12% by weight zinc, 1 to 4% by weight magnesium, optional copper up to about 3% by weight, 0.3 to 2% by weight titanium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium or lutetium, or combinations thereof, impurities of manganese, chromium, silicon, and iron that do not exceed about 0.5% by weight, and aluminum as the remainder. In some embodiments, the alloy does not comprise any intentionally added scandium. Accordingly, the amount of scandium is less than about 0.05% or less than about 0.02% by weight.

[1069] In some embodiments, the aluminum alloys of the present disclosure comprise about 5 to about 7% by weight zinc, 1 to 4% by weight magnesium, optional copper up to about 3% by weight, 0.3 to 2% by weight titanium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium or lutetium, or combinations thereof, impurities of manganese, chromium, silicon, and iron that do not exceed about 0.5% by weight, and aluminum as the remainder. In some embodiments, the alloy does not comprise any intentionally added scandium. Accordingly, the amount of scandium is less than about 0.05% or less than about 0.02% by weight.

[1070] In some embodiments, the 7000-series aluminum alloys of the present disclosure further comprise one or more inoculants. In some embodiments, the one or more inoculants is selected from the group consisting of Sn, In, and Sb.

[1071] In some embodiments, the aluminum as the reminder is an amount of aluminum from about 77 to about 82%, e.g., about 77.2%. about 77.4%, about 77.6%, about 77.8%, about 78%, about 78.2%. about 78.4%, about 78.6%, about 78.8%, about 79%, about 79.2%. about 79.4%, about 79.6%, about 79.8%, about 80%, about 80.2%. about 80.4%, about 80.6%, about 80.8%, about 81%, about 81.2%. about 81.4%, about 81.6%, about 81.8%, or about 82%, including all ranges and values therebetween. In some embodiments, the aluminum as the reminder is an amount of aluminum from about 78 to about 82%. In some embodiments, the aluminum as the reminder is an amount of aluminum from about 79 to about 82%. In some embodiments, the aluminum as the reminder is an amount of aluminum from about 80 to about 82%. In some embodiments, the aluminum as the reminder is an amount of aluminum from about 80.5 to about 82%. In some embodiments, the aluminum as the reminder is an amount of aluminum from about 81 to about 82%. In some embodiments, the aluminum as the reminder is an amount of aluminum from about 80 to about 81%. In some embodiments, the aluminum as the reminder is an amount of aluminum from about 81.5 to about 82%. In some embodiments, the aluminum as the reminder is an amount of aluminum from about 80.5 to about 81.0%.

[1072] The disclosed 7000-series aluminum alloy has been designed to overcome the challenges of welding and additive manufacturing, such as liquation cracking and hot tearing, by undergoing an in situ phase reaction when processed from a molten phase to produce a refined grain size in the final component; such liquid phase processing is inherent to most welding and additive manufacturing processes which utilize an electric arc, laser beam, or electron beam as an energy source. This aluminum alloy, when fabricated into a component, can be heat treated to improve the strength of the component by more than 10%, and in some cases 20%, compared to what is typically obtained from a conventional 7000-series aluminum alloy (e.g. AA7050). In some embodiments, the strength of the component is increased by about 10%, about 12%, about 14%, about 16%, about 18%, or about 20% compared to the strength of a conventional 7000-series aluminum alloy. In some embodiments, the strength is increased from about 10% to about 25% compared to the strength of a conventional 7000-series aluminum alloy. Additionally, this pre-alloyed metal powder can be processed by such powder metallurgy processes as hot isostatic pressing, powder molding, and extrusion, which do not cause a liquid phase to form during the manufacturing process. When processed by such methods, the alloy has mechanical properties and thermal stability exceeding what is expected from a conventional 7000-series alloy.

[1073] In some embodiments, the aluminum alloys of the present disclosure are fabricated into a rod, a wire, a ribbon, chips, a powder, or any other form known in the art. In some embodiments, a rod, a wire, a ribbon, chips, a powder are fabricated from an aluminum alloy of the present disclosure, which is in the form of an ingot or solutionized ingot. In some embodiments, the aluminum alloy is fabricated into a ribbon, chips, or a powder. In some embodiments, the aluminum alloy is fabricated into chips. In some embodiments, the aluminum alloy is fabricated into a rod or a wire. In some embodiments, the aluminum alloy is fabricated into a rod. In some embodiments, the aluminum alloy is fabricated into a wire. In some embodiments, the wire of the present disclosure has an average diameter of from about 0.8 mm to about 5.2 mm, e.g., about 0.8 mm, about 1.2 mm, about 1.6 mm, about 2.0 mm, about 2.4 mm, about 2.8 mm, about 3.2 mm, about 3.6 mm, about 4.0 mm, about 4.4 mm, about 4.8 mm, or about 5.2 mm, including all ranges and values therebetween. In some embodiments, the aluminum alloy is fabricated into a ribbon. In some embodiments, the alloys may be fabricated as a melt-spun ribbon, hot compacted, and extruded into a structure. In some embodiments, the aluminum alloy is fabricated into a powder. In some embodiments, the powder is fabricated by a process selected from the group consisting of gas-atomizing, plasma-atomizing, rotating- electrode processing, or mechanical alloying. In some embodiments, the process further comprises plasma spheridizing. In some embodiments, the powders are spherical shaped. In some embodiments, spherical particles are desirable because they spread nicely for powder bed methods and flow nicely for powder spray methods. Gas atomization generally gives spherical particles with a wide distribution of diameters. In some embodiments, the powders are irregular shaped. Methods such as air or water atomization generally provide irregular shapes (including, but not limited to ligamental and/or globular. [1074] In some embodiments, the powders of the present disclosure have a particle size ranging from about 1 to about 500 pm, e.g., about 1 pm, about 25 pm, about 50 pm, about 75 pm, about 100 pm, about 125 pm, about 150 pm, about 175 pm, about 200pm, about 225 pm, about 250 pm, about 275 pm, about 300 pm, about 325 pm, about 350 pm, about 375 pm, about 400 pm, about 425 pm, about 450 pm, about 475 pm, or about 500 pm, including all ranges and values therebetween. In some embodiments, the powders have a particle size ranging from about 15 to about 75 pm. In some embodiments, powders with a particle size ranging from about 15 to about 75 pm are useful in an additive manufacturing process. In some embodiments, the powder comprises particles having an average particle size dso of less than about 100 pm. In some embodiments, the powder comprises particles having an average particle size dso of from about 5 to about 100 pm, e.g., about 5 pm, about 10 pm, about 15 pm, about 20 pm, about 25 pm, about 30 pm, about 35 pm, about 40 pm, about 45 pm, about 50 pm, about 55 pm, about 60 pm, about 65 pm, about 70 pm, about 75 pm, about 80 pm, about 85 pm, about 90 pm, about 95 pm, or about 100 pm, including all ranges and values therebetween. In some embodiments, the powder comprises particles having an average particle size dso of from about 10 to about 70 pm. In some embodiments, the powdered aluminum alloys of the present disclosure are further processed according to any suitable method known in the art to provide a wire, chips, a ribbon, or the like.

[1075] In some embodiments, the aluminum alloys of the present disclosure are fabricated into a component, the component having a yield strength greater than 580 MPa, an ultimate tensile strength greater 600 MPa, and an elongation at failure of more than 2%. In some embodiments, the yield strength of the component is from about 500 MPa to about 750 MPa, e.g., about 500 MPa, about 550 MPa, about 600 MPa, about 650 MPa, about 700 MPa, or about 750 MPa, including all ranges and values therebetween. In some embodiments, the ultimate tensile strength of the component is from about 500 MPa to about 750 MPa, e.g., about 500 MPa, about 550 MPa, about 600 MPa, about 650 MPa, about 700 MPa, or about 750 MPa, including all ranges and values therebetween. In some embodiments, the component has an elongation at failure of more than 1%, more than 2%, more than 3%, more than 4%, more than 5%, more than 6%, more than 7%, more than 8%, more than 9%, or more than 10%, including all ranges and values therebetween. [1076] In some embodiments, the aluminum alloys of the present disclosure are formed into a sheet, forging, or extrusion. In some embodiments, the sheet, forging, or extrusion is welded to assemble a component.

[1077] In some embodiments, the aluminum alloys of the present disclosure are formed into a rod or wire. In some embodiments, the rod or wire is used a filler material during a melding process to join conventional aluminum alloys, or to join components which have been fabricated from the disclosed alloys. In some embodiments, the composition of the filler material is the same as the aluminum alloy components being joined.

[1078] The aluminum alloys of the present disclosure have numerous advantages over convention 7000-series aluminum alloys. In some embodiments, the aluminum alloys of the present disclosure have enhanced thermal stability, e.g., thermal stability greater than that of a convention 7000-series aluminum alloy. In some embodiments, the aluminum alloys of the present disclosure are high-strength, weldable aluminum alloys. In some embodiments, the alloys of the present disclosure possess a strength to weight ratio at room temperature which is at least as great as that of a conventional 7000-series aluminum alloy. In some embodiments, the strength to weight ratio is about l90 MPa cm ³ /g to about 370 MPa cmVg, e.g., about 190 MPa cmVg, about 200 MPa cmVg, about 210 MPa cmVg, about 220 MPa cmVg, about

230 MPa cmVg, about 240 MPa cmVg, about 250 MPa cmVg, about 260 MPa cmVg, about

270 MPa cmVg, about 280 MPa cmVg, about 290 MPa cmVg, about 300 MPa cmVg, about

310 MPa cmVg, about 320 MPa cmVg, about 330 MPa cmVg, about 340 MPa cmVg, about

350 MPa cmVg, about 360 MPa cmVg, or about 370 MPa cmVg, including all ranges and values therebetween as measured by the ASTM-E8/E8M test for strength and a method of determining density (e.g. ASTM B962). In some embodiments, the aforementioned properties result in the disclosed aluminum alloy being weldable or suitable for use in additive manufacturing.

[1079] In some embodiments of the present disclosure, the average grain size after a solutionizing heat treatment is less than 100 pm. In some embodiments, the average grain size after a solutionizing heat treatment is less than 95 pm. In some embodiments, the average grain size after a solutionizing heat treatment is less than 90 pm. In some embodiments, the average grain size after a solutionizing heat treatment is less than 85 pm. In some embodiments, the average grain size after a solutionizing heat treatment is less than 80 pm. In some embodiments, the average grain size after a solutionizing heat treatment is less than 75 pm. In some embodiments, the average grain size after a solutionizing heat treatment is less than 70 pm. In some embodiments, the average grain size after a solutionizing heat treatment is less than 65 pm. In some embodiments, the average grain size after a solutionizing heat treatment is less than 60 pm. In some embodiments, the average grain size after a solutionizing heat treatment is less than 55 gm. In some embodiments, the average grain size after a solutionizing heat treatment is less than 50 gm. In some embodiments, the average grain size after a solutionizing heat treatment is less than 45 gm. In some embodiments, the average grain size after a solutionizing heat treatment is less than 40 gm. In some embodiments of the present disclosure, the average grain size after a solutionizing heat treatment is from about 40 to about 100 gm, e.g., about 40 gm, about 45 gm, about 50 gm, about 55 gm, about 60 gm, about 65 gm, about 70 gm, about 75 gm, about 80 gm, about 85 gm, about 90 gm, about 95 gm, or about 100 gm, including all ranges and values therebetween. In some embodiments, refining grain size in this manner results in the disclosed aluminum alloy being free of liquation cracking and hot tearing during a welding or additive manufacturing process.

[1080] In some embodiments, the aluminum alloy of the present disclosure or component fabricated from an aluminum alloy of the present disclosure has a tensile strength at least as great as that of a conventional 7000-series aluminum alloy. In some embodiments, the tensile strength of the disclosed aluminum alloy ranges from about 50 to about 750 MPa, e.g., about 50 MPa, about 100 MPa, about 150 MPa, about 200 MPa, about 250 MPa, about 300 MPa, about 350 MPa, about 400 MPa, about 450 MPa, about 500 MPa, about 550 MPa, about 600 MPa, about 650 MPa, about 700 MPa, or about 750 MPa, including all ranges and values therebetween. In some embodiments, the tensile strength is greater than about 350 MPa. In some embodiments, the tensile strength is greater than about 450 MPa. In some embodiments, the tensile strength is greater than about 500 MPa. In some embodiments, the tensile strength is greater than about 550 MPa. In some embodiments, the tensile strength is greater than about 600 MPa. In some embodiments, the tensile strength is greater than about 650 MPa. In some embodiments, the tensile strength is greater than about 700 MPa. In some embodiments, the tensile strength is greater than about 750 MPa.

[1081] In some embodiments, the aluminum alloy of the present disclosure or component fabricated from an aluminum alloy of the present disclosure has a shear strength at least as great as that of a conventional 7000-series aluminum alloy. In some embodiments, the shear strength of the disclosed aluminum alloy ranges from about 50 to about 400 MPa, e.g., about 50 MPa, about 75 MPa, about 100 MPa, about 125 MPa, about 150 MPa, about 175 MPa, about 200 MPa, about 225 MPa, about 250 MPa, about 275 MPa, about 300 MPa, about 325 MPa, about 350 MPa, about 375 MPa, or about 400 MPa, including all ranges and values therebetween. In some embodiments, the shear strength is about 250 MPa. In some embodiments, the shear strength is about 300 MPa. In some embodiments, the shear strength is greater that about 200 MPa.

[1082] In some embodiments, the aluminum alloy of the present disclosure or component fabricated from an aluminum alloy of the present disclosure has a yield strength at least as great as that of a conventional 7000-series aluminum alloy. In some embodiments, the yield strength of the disclosed aluminum alloy ranges from about 150 to about 600 MPa, e.g., about 150 MPa, about 175 MPa, about 200 MPa, about 225 MPa, about 250 MPa, about 275 MPa, about 300 MPa, about 325 MPa, about 350 MPa, about 375 MPa, about 400 MPa, about 425 MPa, about 450 MPa, about 475 MPa, about 500 MPa, about 525 MPa, about 550 MPa, about 575 MPa, or about 600 MPa, including all ranges and values therebetween. In some embodiments, the yield strength is greater than about 450 MPa. In some embodiments, the yield strength is greater than about 500 MPa. In some embodiments, the yield strength is greater than about 550 MPa. In some embodiments, the yield strength is greater than about 580 MPa.

[1083] In some embodiments, the aluminum alloy of the present disclosure or component fabricated from an aluminum alloy of the present disclosure has a modulus of elasticity at least as great as that of a conventional 7000-series aluminum alloy. In some embodiments, the modulus of elasticity of the disclosed aluminum alloy ranges from about 50 to about 80 GPa, e.g., about 50 GPa, about 52.5 GPa, about 55 GPa, about 57.5 GPa, about 60 GPa, about 62.5 GPa, about 65 GPa, about 67.5 GPa, about 70 GPa, about 72.5 GPa, about 75 GPa, about 77.5 GPa, or about 80 GPa, including all ranges and values therebetween. In some embodiments, the modulus of elasticity is about 65 GPa. In some embodiments, the modulus of elasticity is about 70 GPa. In some embodiments, the modulus of elasticity is about 75 GPa. In some embodiments, the modulus of elasticity is about 80 GPa. In some embodiments, the modulus of elasticity is greater that about 75 GPa.

[1084] In some embodiments, the aluminum alloy of the present disclosure or component fabricated from an aluminum alloy of the present disclosure has an elongation at failure of from about 1 to about 15%. In some embodiments, the aluminum alloy of the present disclosure or component fabricated from an aluminum alloy of the present disclosure has an elongation at failure of from about 2 to about 10%. In the elongation at failure is more than about 2%, more than about 3%, more than about 4%, more than about 5%, more than about 6%, more than about 7%, more than about 8%, more than about 9%, or more than about 10%. In some embodiments, the elongation at failure is more than about 2%. In some embodiments, the elongation at failure is more than about 3%. In some embodiments, the elongation at failure is more than about 4%. In some embodiments, the elongation at failure is more than about 5%.

[1085] In some embodiments, an aluminum alloy component (e.g., a net-shape or a near- net-shape) component fabricated from a 7000-series aluminum alloy of the present disclosure (e.g., by a process such as additive manufacturing or powder metallurgy) possesses a tensile strength, shear strength, yield strength, and/or a modulus of elasticity as defined above.

[1086] In some embodiments, based on the foregoing properties, the structure fabricated from the alloy, in any of its forms, may be used in an application where very high strength and low density is desired, such as in an aerospace component, a satellite component, an automotive component, in a transportation application, in a sporting good or leisure equipment, or in a consumer product.

[1087] As noted above, in some embodiments, the aluminum alloys of the present disclosure are in the form of powders. In some embodiments, the aluminum alloy powders disclosed herein are useful in additive manufacturing processes. In some embodiments, the aluminum alloy powders that are useful in additive manufacturing processes are spherical metal alloy powders. In some embodiments, the spherical metal powders are formed using gas- atomization, plasma-atomization, or plasma-spherization.

[1088] In some embodiments, the aluminum alloys disclosed herein are useful in joining techniques, including, but not limited to welding. Without being bound by any particular theory, the utility of the disclosed aluminum alloys may be a result of their reduced or eliminated tendency to undergo hot-cracking or liquation-cracking when subjected to the above processes.

Methods

[1089] In some embodiments, a method of producing a weldable 7000-series aluminum alloy is provided, the method comprising: a) melting recycled or virgin aluminum, while adding aluminum-master alloys or pure elements, at a temperature of about 700°C to about l000°C to form a liquid mixture of constituents, the liquid mixture of constituents comprising about 4 to about 12% by weight zinc, about 1 to about 4% by weight magnesium, about 0.3 to about 2% by weight of a transition metal or a rare earth metal, and aluminum as the remainder, and wherein the constituents do not comprise any intentionally added scandium; b) casting the melted constituents into an ambient or a chilled casting mold to form a casted ingot; c) heat- treating the casted ingot at a temperature of about 400°C to about 480°C for a time of about 0.25 hours to about 6 hours to form a solutionized ingot comprising an Al-Zn-Mg solid-solution with a dispersion of Lb structured AbZr nano-scale precipitates; and d) hot-forming and/or cold-forming the solutionized ingot into a sheet, a foil, a rod, a wire, an extrusion, or a forging.

[1090] In some embodiments, a method of producing a weldable 7000-series aluminum alloy is provided, the method comprising: a) melting recycled or virgin aluminum, while adding aluminum-master alloys or pure elements, at a temperature of about 700°C to about l000°C to form a liquid mixture of constituents, the liquid mixture of constituents comprising about 4 to about 12% by weight zinc, about 1 to about 4% by weight magnesium, about 0.3 to about 2% by weight of a transition metal, and aluminum as the remainder, and wherein the constituents do not comprise any intentionally added scandium; b) casting the melted constituents into an ambient or a chilled casting mold to form a casted ingot; c) heat-treating the casted ingot at a temperature of about 400°C to about 480°C for a time of about 0.25 hours to about 6 hours to form a solutionized ingot comprising an Al-Zn-Mg solid-solution with a dispersion of Lb structured AbZr nano-scale precipitates; and d) hot-forming and/or cold forming the solutionized ingot into a sheet, a foil, a rod, a wire, an extrusion, or a forging.

[1091] In some embodiments, the transition metal in the liquid mixture of constituents is selected from the group consisting of titanium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, and yttrium. In some embodiments, the transition metal in the liquid mixture of constituents in zirconium.

[1092] In some embodiments, the rare earth metal is selected from the group consisting of lanthanum, cerium, praseodymium, neodymium, gadolinium, dysprosium, erbium, ytterbium, or combinations thereof.

[1093] In some embodiments, the amount of zinc in the liquid mixture of constituents is from about 4 to about 12% by weight zinc, e.g., about 4%, about 4.5%, about 5%, about 5.5%, about 6%, about 6.5%, about 7%, about 7.5%, about 8%, about 8.5%, about 9%, about 9.5%, about 10%, about 10.5%, about 11%, about 11.5%, or about 12%, including all ranges and values therebetween. In some embodiments, the alloys of the present disclosure comprise about 5 to about 12% by weight zinc, about 6 to about 12% by weight zinc, about 7 to about 12%, about 8 to about 12%, about 9 to about 12%, about 10 to about 12%, about 5 to about 11%, about 6 to about 11%, about 7 to about 11%, about 8 to about 11%, about 4 to about 10%, about 5 to about 10%, about 6 to about 10%, about 7 to about 10%, about 8 to about 10%, about 4 to about 9%, about 5 to about 9%, about 6 to about 9%, about 7 to about 9%, about 4 to about 8%, about 5 to about 8%, about 6 to about 8%, about 4 to about 7%, about 5 to about 7%, about 4 to about 6%, including all ranges and values therebetween. In some embodiments, the amount of zinc in the liquid mixture of constituents is about 10% by weight zinc. In some embodiments, the amount of zinc in the liquid mixture of constituents is about 11% by weight zinc. In some embodiments, the amount of zinc in the liquid mixture of constituents is about 12% by weight zinc.

[1094] In some embodiments, the amount of magnesium in the liquid mixture of constituents is from about 1 to about 4% by weight magnesium, e.g., about 1%, about 1.25%, about 1.5%, about 1.75%, about 2%, about 2.25%, about 2.5%, about 2.75%, about 3%, about 3.25%, about 3.5%, about 3.75%, or about 4%, including all ranges and values therebetween. In some embodiments, the amount of magnesium in the liquid mixture of constituents is about 1.5% by weight magnesium. In some embodiments, the amount of magnesium in the liquid mixture of constituents is about 2% by weight magnesium. In some embodiments, the amount of magnesium in the liquid mixture of constituents is about 2.5% by weight magnesium. In some embodiments, the amount of magnesium in the liquid mixture of constituents is about 3% by weight magnesium.

[1095] In some embodiments, the temperature of step a) is about 700 °C, about 725 °C, about 750 °C, about 775 °C, about 800 °C, about 825 °C, about 850 °C, about 875 °C, 900 °C, about 925 °C, about 950 °C, about 975 °C, or about 1000 °C, including all ranges and values therebetween. In some embodiments, the temperature of step a) is from about 750 °C to about 1000 °C. In some embodiments, the temperature of step a) is from about 800 °C to about 1000 °C. In some embodiments, the temperature of step a) is from about 850 °C to about 1000 °C. In some embodiments, the temperature of step a) is from about 900 °C to about 1000 °C.

[1096] In some embodiments, step a) includes the constituents zinc (Zn), magnesium (Mg), and zirconium (Zr) in any amount or range described above for the aluminum alloys of the present disclosure.

[1097] In some embodiments, the constituents of step a) further comprise about 0.0 to about 4% by weight copper, e.g., about 0%, about 0.25%, about 0.50%, about 0.75%, about 1%, about 1.25%, about 1.50%, about 1.75%, about 2%, about 2.25%, about 2.50%, about 2.75%, about 3%, about 3.25%, about 3.50%, about 3.75%, or about 4% by weight copper, including all ranges and values therebetween. In some embodiments, the amount of copper is less than about 4% by weight copper, less than about 3% by weight copper, less than about 2% by weight copper, or less than about 1% by weight copper. In some embodiments, the amount of copper is up to about 3% by weight. In some embodiments, when copper is present, the solutionized ingot comprises an Al-Zn-Mg-Cu solid-solution with the dispersion of Lb structured AbZr nano-scale precipitates.

[1098] As noted, the constituents of the liquid mixture of step a) comprise no intentionally added scandium. Accordingly, in some embodiments, the liquid mixture of constituents in step a) comprises less than about 0.5% scandium, less than about 0.5% scandium, less than about 0.3% scandium, less than about 0.2% scandium, less than about 0.1% scandium, or less than about 0.05% scandium, none of which has been intentionally added to the aluminum alloys of the present disclosure.

[1099] In some embodiments, step b) of the method of producing a weldable 7000-series aluminum alloy includes casting the melted constituents into an ambient casting mold to form a casted ingot. In some embodiments, step b) of the method of producing a weldable 7000- series aluminum alloy includes casting the melted constituents into a chilled casting mold to form a casted ingot. In some embodiments, the chilled coasting mold is at a temperature below about 20 °C, below about l5°C, below about 10 °C, below about 5°C, or below about 0 °C. In some embodiments, the chilled casting mold is from about 0 °C to about 15 °C, e.g., about 0 °C, about 3 °C, about 6 °C, about 9 °C, about 12 °C, or about 15 °C, including all ranges and values therebetween. In some embodiments, the chilled casting mold is from about 5 °C to about 10 °C. In some embodiments, the chilled casting mold is from about 0 °C to about 10 °C.

[1100] In some embodiments, the heat-treating the casted ingot of step c) occurs at a temperature of about 400 °C, about 410 °C, about 420 °C, about 430 °C, about 440 °C, about 450 °C, about 460 °C, about 470 °C, or about °C, including all ranges and values therebetween. In some embodiments, the heat-treating the casted ingot of step c) occurs for a time of about 0.25 h, about 0.5 h, about 0.75 h, about 1 h, about 1.25 h, about 1.5 h, about 1.75 h, about 2 h, about 2.25 h, about 2.5 h, about 2.75 h, about 3 h, about 3.25 h, about 3.5 h, about 3.75 h, about 4 h, about 4.25 h, about 4.5 h, about 4.75 h, about 5 h, about 5.25 h, about 5.5 h, about 5.75 h, or about 6 hours, including all ranges and values therebetween, to form a solutionized ingot comprising an Al-Zn-Mg solid-solution with a dispersion of Lb structured AbZr nano-scale precipitates. [1101] In some embodiments, the hot-forming and/or cold-forming of the solutionized ingot of step d) provides a sheet. In some embodiments, the hot-forming and/or cold-forming of the solutionized ingot of step d) provides a foil. In some embodiments, the hot-forming and/or cold-forming of the solutionized ingot of step d) provides a rod. In some embodiments, the hot-forming and/or cold-forming of the solutionized ingot of step d) provides a wire. In some embodiments, the hot-forming and/or cold-forming of the solutionized ingot of step d) provides an extrusion. In some embodiments, the hot-forming and/or cold-forming of the solutionized ingot of step d) provides a forging.

[1102] In some embodiments, the method of producing a weldable 7000-series aluminum alloy further comprises step e) heat-aging the formed sheet, foil, rod, wire, extrusion, or forging at a temperature of about l00°C to about l80°C for a time of about 1 hour to about 48 hours.

[1103] In some embodiments, the heat-aging of step e) is carried out at about 100 °C, about 105 °C, about 100 °C, about 105 °C, about 100 °C, about 105 °C, about 100 °C, about 105 °C, about 100 °C, about 105 °C, about 100 °C, about 105 °C, about 100 °C, about 105 °C, about 100 °C, about 105 °C, or about 180 °C, including all ranges and values therebetween.

[1104] In some embodiments, the heat-aging of step e) is for a time of about 1 h, about 2 h, about 3 h, about 4 h, about 5 h, about 6 h, about 7 h, about 8 h, about 9 h, about 10 h, about 11 h, about 12 h, about 13 h, about 14 h, about 15 h, about 16 h, about 17 h, about 18 h, about

19 h, about 20 h, about 21 h, about 22 h, about 23 h, about 24 h, about 25 h, about 26 h, about

27 h, about 28 h, about 29 h, about 30 h, about 31 h, about 32 h, about 33 h, about 34 h, about

35 h, about 36 h, about 37 h, about 38 h, about 39 h, about 40 h, about 41 h, about 42 h, about

43 h, about 44 h, about 45 h, about 46 h, about 47 h, or about 48 h, including all ranges and values therebetween. In some embodiments, the heat-aging of step e) is for a time of about 1 h to about 10 h. In some embodiments, the heat-aging of step e) is for a time of about 1 h to about 5 h. In some embodiments, the heat-aging of step e) is for a time of about 1 h to about 3 h. In some embodiments, the heat-aging of step e) is for a time of about 5 h to about 20 h. In some embodiments, the heat-aging of step e) is for a time of about 5 h to about 15 h. In some embodiments, the heat-aging of step e) is for a time of about 5 h to about 10 h.

[1105] In some embodiments, the aluminum alloys disclosed herein are produced by a rapid solidification process, as described in E.J. Lavernia et al. Journal of Material Science 2010, 45, 287-325, the disclosure of which is hereby incorporated by reference in its entirety. In some embodiments, the rapid solidification process is selected from the group consisting of melt spinning, melt extraction, beam glazing, spray deposition, gas atomization, plasma atomization, and plasma spherization. In some embodiments, the rapid solidification process is defined by a cooling rate of from about 10 ² to about 10 ⁷ Ks ¹ , e.g., about 10 ² Ks ¹ , about 10 ³ Ks ¹ , about 10 ⁴ Ks ¹ , about 10 ⁵ Ks ¹ , about 10 ⁶ Ks ¹ , or about 10 ⁷ Ks ¹ , including all ranges and values therebetween.

[1106] Melt spinning is a convenient and economic method for fabricating metallic ribbons at industrial scales. In some applications of melt spinning, the substance (e.g., an aluminum alloy) is melted for extrusion through a spinneret and then directly solidified by cooling. In some embodiments, melt spinning further produces non-equilibrium phases such as nanocrystalline phases, quasi-crystalline phases, and a supersaturated solid solutions. In some embodiments, the aluminum alloys produced from melt spinning are in the form of ribbons (i.e., thin strips. In some embodiments, melt spinning produces ribbons comprising amorphous aluminum alloys and/or glassy aluminum alloys.

[1107] Spray deposition, also known as spray casting, spray forming and in-situ compaction, is a method of casting near net shape metal components with homogeneous microstructures via the deposition of semi-solid sprayed droplets onto a shaped substrate. In some embodiments, the spay deposition method is selected from the group consisting of cold gas spraying, plasma spraying (vacuum, atmospheric, and the like), high-velocity oxy-fuel spraying (HVOF), gas-assisted spray forming, or combustion flame spraying. In some embodiments, spray deposition involves the atomization of molten metal, but instead of being allowed to solidify as powder, the spray is collected on a substrate to form billets for subsequent forging. In some embodiments, spray deposition is used to form tubes, strips, sheets, or near- net shape pre-forms of 7000-series aluminum alloys.

[1108] In plasma spherization, non-spherical powders are melted in a plasma beam to form spherical particles. In some embodiments, a gas (e.g., N2, Ar) is used to transport the powder. In some embodiments, this method is useful in producing aluminum alloys of the present disclosure having high melting points. In some embodiments, plasma spherization is used to transform irregular shaped 7000-series aluminum alloy particles into spherical powders of a 7000-series aluminum alloy. In some embodiments, the spherical powders thus produced have a uniform composition.

[1109] Plasma atomization is also useful for preparing spherical powders of 7000-series aluminum alloys. In some embodiments, plasma atomization is used to transform feedstock 7000-series aluminum alloy into spherical powders of a 7000-series aluminum alloy. In some embodiments, the spherical powders thus produced have a uniform composition. In some embodiments, 7000-series aluminum alloy wire feedstock is fed into a plasma torch that, with the aid of gases, atomises the wire into a spherical metal powder. In some embodiments, the size of the powder particles ranges from about 1 to about 200 pm, including all ranges and values therebetween.

[1110] Another method of metal powder production is gas atomization. In some embodiments, the aluminum alloy feedstock is melted under an air or inert gas blanket, or under vacuum. The chamber can then be backfilled with gas to force molten alloy through a nozzle where high velocity air, nitrogen, helium, or argon gas impinges onto the flowing melt and breaks it up. The resulting powder is mostly spherical. In some embodiments, small amounts of asymmetric particles and satellites (i.e., small particle adhering to a larger one) are present.

[1111] In some embodiments, the rapid solidification process results in the formation of primary crystallites that are about 10 pm or less in diameter. In some embodiments, the primary crystallites are less than about 10 pm, less than about 9 pm, less than about 8 pm, less than about 7 pm, less than about 6 pm, less than about 5 pm, less than about 4 pm, less than about 3 pm, less than about 2 pm, or less than about 1 pm, including all ranges and values therebetween. In some embodiments the rapid solidification process results in extended ranges of solid solutions.

[1112] Generally, because of the rapid solidification of the metal alloy during the atomizing process, the powders may consist primarily of a solid solution of the alloying elements but may also contain intermetallic phases (e.g., AbZr). If the metal alloy powders are synthesized by a mechanically alloying process, which is a solid-state process that does not include quenching a molten alloy into a solid, the mechanical energy input is enough so that the metal alloy powders will still consist primarily of a solid solution of the alloying elements but may also contain secondary intermetallic phases. The presence of secondary intermetallic phases is considered neither a detrimental nor beneficial attribute of the metal alloy powders if they are to be used in an additive manufacturing process which forms a liquid phase in the alloy; such intermetallic phases may be considered beneficial for the metal alloy powders if they are to be used in a powder metallurgy process which does not form a liquid phase, and the method of fabricating a powder may be adjusted in such a way as to promote the formation of secondary intermetallic phases in the metal alloy powder. [1113] The method disclosed herein may include fabricating a component using a manufacturing technique that utilizes welding where the disclosed alloy is utilized as the base material or as a filler material. In some embodiments, the 7000-series aluminum alloy rods and wires described above are used as filler material to join two aluminum alloy components in a welding process. Accordingly, a method of preparing a welded metallic assembly is provided, the method comprising joining two aluminum alloy components with a filler material in a welding process, wherein the filler material joining the components is the wire or the rod fabricated from a 7000-series aluminum alloy of the present disclosure, and wherein the two aluminum alloy components are each independently selected from the group consisting of Al- Zn-Mg alloys, Al-Zn-Mg-Cu alloys, Al-Zn-Mg-Zr alloys, and Al-Zn-Mg-Cu-Zr alloys. In some embodiments, the filler material is a rod fabricated from a 7000-series aluminum alloy of the present disclosure. In some embodiments, the filler material is a wire fabricated from a 7000-series aluminum alloy of the present disclosure. In some embodiments, the filler material is a sheet fabricated from a 7000-series aluminum alloy of the present disclosure.

[1114] In some embodiments, the welding process is selected from the group consisting of arc-welding, torch-welding, laser-beam-welding, and electron-beam-welding. In some embodiments, the welding process does not result in liquation cracking and/or hot tearing of the welded metallic assembly. Thus, in some embodiments, the welded metallic assembly is free of liquation cracks and hot cracks.

[1115] In some embodiments, the filler material and the two aluminum alloy components have the same composition. Accordingly, in some embodiments, the filler material and the two aluminum alloy components each independently selected from the group consisting of Al- Zn-Mg alloys, Al-Zn-Mg-Cu alloys, Al-Zn-Mg-Zr alloys, and Al-Zn-Mg-Cu-Zr alloys comprise about 4 to about 12% by weight zinc, about 1 to about 4% by weight magnesium, about 0.3 to about 2% zirconium when present, and up to about 3% copper when present. As noted above, neither the filler material, nor the aluminum alloy components have any intentionally added scandium.

[1116] The 7000-series aluminum alloys disclosed herein are suitable for use in various additive manufacturing processes due to their beneficial properties including, but not limited to weldability and high strength to weight ratios. Examples of additive manufacturing processes are disclosed in U.S. Patent No. 10,124,408, which is incorporated herein by reference in its entirety. Fig. 7 provides a non-limiting overview of some additive manufacturing processes applicable to aluminum alloys. [1117] In some embodiments, the present disclosure provides a method of manufacturing a net-shape component or a near-net-shape component, the method comprising subjecting an aluminum alloy of the present disclosure to an additive manufacturing process (e.g., an additive layering manufacturing process) to manufacture the net-shape component or the near-net-shape component. In some embodiments, the aluminum alloy is a rod, a wire, a ribbon, a powder, or chips. In some embodiments, the aluminum alloy is a wire. In some embodiments, the aluminum alloy is a powder. In some embodiments, the powder is a spherical aluminum alloy powder. The method may include using a pre-alloyed metal powders to fabricate a structure using an additive manufacturing (or powder metallurgy) process, where the method may include the formation of a liquid phase.

[1118] In some embodiments, the additive manufacturing process is powder bed fusion or selective laser melting. In some embodiments, the additive manufacturing process is powder bed fusion. In some embodiments, the additive manufacturing process is selective laser melting. In some embodiments of a powder bed fusion or selective laser melting process, a laser is used to melt the powders and fuse them together into a net-shape, or near-net-shape component.

[1119] In some embodiments, the additive manufacturing process is powder directed energy deposition. In some embodiments of a powder directed energy deposition process, a laser is used to melt blown powders and fuse them onto a net-shape, or near-net-shape component.

[1120] In some embodiments, the additive manufacturing process includes subjecting the aluminum alloy to a focused energy source. In some embodiments, the focused energy source is selected from the group consisting of a laser beam and an electron beam. In some embodiments, the focused energy source is a laser beam. In some embodiments, the laser beam is a pulsed energy laser beam. In some embodiments, the focused energy source is an electron beam.

[1121] In some embodiments of the additive manufacturing process, the focused energy source is used to fully melt the aluminum alloy. In some embodiments, the fully melted aluminum alloy is deposited as a layer to a preexisting substrate or a previously deposited layer of the aluminum alloy. In some embodiments, deposited layer of the aluminum alloy undergoes rapid solidification to fuse the material to the preexisting substrate or the previously deposited layer of the aluminum alloy. In some embodiments, the rapid solidification occurs at a cooling rate of about 10 ² to about 10 ⁸ Ks ¹ , e.g., about 10 ² Ks ¹ , about 10 ³ Ks ¹ , about 10 ⁴ Ks ¹ , about 10 ⁵ Ks ¹ , about 10 ⁶ Ks ¹ , about 10 ⁷ Ks ¹ , or about 10 ⁸ Ks ¹ , including all ranges and values therebetween. In some embodiments, the rapid solidification occurs at a cooling rate of at least about 10 ⁷ Ks ¹ . In some embodiments, the rapid solidification occurs at a cooling rate greater than about 10 ⁷ Ks ¹ . As described herein, the net-shape components or near-net shape components prepared using the 7000-series aluminum alloys of the present disclosure avoid liquation cracking and hot cracking as a result of the beneficial properties of the disclosed aluminum alloy materials.

[1122] In some embodiments, the additive manufacturing process disclosed herein further comprises heat-aging the net-shape or near-net-shape component at a temperature of about l00°C to about l80°C for a time of about 1 hour to about 48 hours, to achieve a simultaneous dispersion of fine-scale ZmMg precipitates, primary precipitates, and Al-X nano-scale precipitates, and resulting in the component having a strength which is at least as great as that of a net-shape or near-net-shape component conventionally manufactured from a conventional 7000-series aluminum alloy. In some embodiments, the primary precipitates have an average diameter ranging from about 0.1 to about 10 pm, e.g., about 0.1 pm, about 0.5 pm, about 1 pm, about 1.5 pm, about 2 pm, about 2.5 pm, about 3 pm, about 3.5 pm, about 4 pm, about 4.5 pm, about 5 pm, about 5.5 pm, about 6 pm, about 6.5 pm, about 7 pm, about 7.5 pm, about 8 pm, about 8.5 pm, about 9 pm, about 9.5 pm, or about 10 pm, including all ranges and values therebetween. In some embodiments, the primary precipitates have an average diameter ranging from about 0.5 to about 1.5 pm. In some embodiments, the primary precipitates have an average diameter ranging from about 0.1 to about 1.5 pm. In some embodiments, the primary precipitates are Al-X primary precipitates. In some embodiments, X is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Y, La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu. In some embodiments, X is Zr. In some embodiments, the primary precipitates are AbZr primary precipitates. In some embodiments, the Al-X nano-scale precipitates have an average diameter ranging from about 1 to about 100 nm, e.g., about 1 nm, about 2 nm, about 4 nm, about 6 nm, about 8 nm, about 10 nm, about 12 nm, about 14 nm, about 16 nm, about 18 nm, about 20 nm, about 22 nm, about 24 nm, about 26 nm, about 28 nm, about 30 nm, about 32 nm, about 34 nm, about 36 nm, about 38 nm, about 40 nm, about 42 nm, about 44 nm, about 46 nm, about 48 nm, about 50 nm, about 52 nm, about 54 nm, about 56 nm, about 58 nm, about 60 nm, about 62 nm, about 64 nm, about 66 nm, about 68 nm, about 70 nm, about 72 nm, about 74 nm, about 76 nm, about 78 nm, about 80 nm, about 82 nm, about 84 nm, about 86 nm, about 88 nm, about 90 nm, about 92 nm, about 94 nm, about 96 nm, about 98 nm, or about 100 nm, including all ranges and values therebetween. In some embodiments, the Al-X nano-scale precipitates have an average diameter ranging from about 3 to about 50 nm. In some embodiments, the AbZr nano-scale precipitates have an average diameter ranging from about 3 to about 20 nm. In some embodiments, the Al-X nano-scale precipitates have an average diameter ranging from about 3 to about 10 nm. In some embodiments, X is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Y, La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu. In some embodiments, the nano-scale precipitates are AbZr nano-scale precipitates.

[1123] In some embodiments, heat-aging the net-shape component or near-net- shape component is carried out at a temperature of about l00°C, about H0°C, about l20°C, about l30°C, about l40°C, about l50°C, about l60°C, about l70°C, or about l80°C, including all ranges and values therebetween.

[1124] In some embodiments, the heat-aging the net-shape component or near-net-shape component is for a time of about 1 h, about 2 h, about 3 h, about 4 h, about 5 h, about 6 h, about 7 h, about 8 h, about 9 h, about 10 h, about 11 h, about 12 h, about 13 h, about 14 h, about 15 h, about 16 h, about 17 h, about 18 h, about 19 h, about 20 h, about 21 h, about 22 h, about 23 h, about 24 h, about 25 h, about 26 h, about 27 h, about 28 h, about 29 h, about 30 h, about 31 h, about 32 h, about 33 h, about 34 h, about 35 h, about 36 h, about 37 h, about 38 h, about 39 h, about 40 h, about 41 h, about 42 h, about 43 h, about 44 h, about 45 h, about 46 h, about 47 h, or about 48 h, including all ranges and values therebetween. In some embodiments, the heat- aging of step is for a time of about 1 h to about 10 h. In some embodiments, the heat-aging of step is for a time of about 1 h to about 5 h. In some embodiments, the heat-aging of step is for a time of about 1 h to about 3 h. In some embodiments, the heat-aging of step is for a time of about 5 h to about 20 h. In some embodiments, the heat-aging of step is for a time of about 5 h to about 15 h. In some embodiments, the heat-aging of step is for a time of about 5 h to about 10 h.

[1125] In some embodiments of the additive manufacturing process, prior to the heat-aging step, the net-shape component or near-net-shape component is heat treated at a temperature of about 400°C to about 480°C for a time of about 0.25 hours to about 6 hours. In some embodiments, the temperature for heat-treating is about 400°C, about 4lO°C, about 420°C, about 430°C, about 440°C, about 450°C, about 460°C, about 470°C, or about 480°C, including all ranges and values therebetween. In some embodiments, heat-aging is for a time of about 0.25 h, about 0.5 h, about 0.75 h, about 1 h, about 1.25 h, about 1.5 h, about 1.75 h, about 2 h, about 2.25 h, about 2.5 h, about 2.75 h, about 3 h, about 3.25 h, about 3.5 h, about 3.75 h, about 4 h, about 4.25 h, about 4.5 h, about 4.75 h, about 5 h, about 5.25 h, about 5.5 h, about 5.75 h, or about 6 hours, including all ranges and values therebetween.

[1126] In some embodiments, a method of manufacturing an aluminum alloy component comprises using a wire produced by the methods disclosed herein in an additive manufacturing process to manufacture a net-shape or a near-net-shape component. In some embodiments, the method comprises heat-treating the net shape or near net shape component at a temperature of about 400°C to about 480°C for a time of about 0.25 hours to about 6 hours, after the wire using step and before the heat-aging step. In some embodiments, the method further comprises, after the heating treating step, heat-aging the net-shape or near-net-shape component at a temperature of about l00°C to about l 80°C for a time of about 1 hour to about 48 hours, to achieve a simultaneous dispersion of fine-scale ZmMg precipitates, primary precipitates having an average diameter of about 0.1 to about 10 pm, and Al-X nano-scale precipitates having an average diameter of about 1 to about 100 nm, and resulting in the component having a strength which is at least as great as that of a component conventionally manufactured from a conventional 7000-series aluminum alloy. In some embodiments, X is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Y, La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu. In some embodiments, X is Zr.

[1127] The present disclosure also provides a method of manufacturing a net-shape component, a near-net-shape component, or a component extruded from a billet, the method comprising subjecting the ribbon, chips, or powder fabricated from a 7000-series aluminum alloy disclosed herein to a powder metallurgy process to manufacture the net-shape component, the near-net-shape component, or the component extruded from a billet. In some embodiments, the powder metallurgy process includes hot pressing, hot isostatic pressing, cold isostatic pressing, powder molding, hot extrusion, or extrusion.

[1128] Fig. 8 provides an overview of some of the steps in a general powder metallurgy process. In some embodiments, powder metallurgy includes blending a powder fabricated from a 7000-series aluminum alloy of the present disclosure to form a homogenous mass with uniform distribution of particle size and composition. In some embodiments, the powder metallurgy process further involves pressing or compacting the powder (e.g., powder particles) fabricated from a 7000-series aluminum alloy of the present disclosure in a die and sintering the powder to fuse (or bond) the particles together. In some embodiments, the pressing is carried out at high pressure. In some embodiments, the sintering carried out at a temperature from about 300 °C to about 650 °C, e.g., about 300 °C, about 325 °C, about 350 °C, about 375 °C, about 400 °C, about 425 °C, about 450 °C, about 475 °C, about 500 °C, about 525 °C, about 550 °C, about 575 °C, about 600 °C, about 625 °C, or about 650 °C, including all ranges and values therebetween. In some embodiments, the sintering temperature is below the melting temperature of the major component in the aluminum alloy. In some embodiments, being below the melting means carrying out the sintering process at a temperature that is from about 70-90% of the melting point of the metal. In some embodiments, the sintering is carried out under inert atmosphere conditions, such as argon or nitrogen. After cooling and optional secondary processing, the finished product is obtained.

[1129] In some embodiments, the aluminum alloy powder of the present disclosure for use in the powder metallurgy process is prepared by a rapid solidification process. In some embodiments the process results in the formation of a powder comprising a solid solution of the alloying elements (Mg, Zn, Zr, etc.). In some embodiments, the powder further comprises one or more secondary intermetallic phases. In some embodiments, the disclosed powder metallurgy process is modified by any suitable method to promote the formation of intermetallic phases.

[1130] In some embodiments, the powder metallurgy process disclosed herein comprises heating treating the net-shape component, the near-net-shape component, or the component extruded from the billet at a temperature of about 400°C to about 480°C (e.g., about 400°C, about 4lO°C, about 420°C, about 430°C, about 440°C, about 450°C, about 460°C, about 470°C, or about 480°C, including all ranges and values therebetween) for a time of about 0.25 hours to about 6 hours (e.g., 0.25 h, about 0.5 h, about 0.75 h, about 1 h, about 1.25 h, about 1.5 h, about 1.75 h, about 2 h, about 2.25 h, about 2.5 h, about 2.75 h, about 3 h, about 3.25 h, about 3.5 h, about 3.75 h, about 4 h, about 4.25 h, about 4.5 h, about 4.75 h, about 5 h, about 5.25 h, about 5.5 h, about 5.75 h, or about 6 hours, including all ranges and values therebetween).

[1131] In some embodiments, the powder metallurgy process disclosed herein further comprises heat-aging the net-shape component, the near-net-shape component, or the component extruded from the billet at a temperature of about l00°C to about l80°C for a time of about 1 hour to about 48 hours, to achieve a simultaneous dispersion of fine-scale Z Mg precipitates, primary precipitates, and AbZr nano-scale precipitates, and resulting in the component having a strength which is at least as great as that of a net-shape or near-net-shape component conventionally manufactured from a conventional 7000-series aluminum alloy. In some embodiments, the primary precipitates have an average diameter ranging from about 0.1 to about 10 pm, e.g., about 0.1 pm, about 0.5 pm, about 1 pm, about 1.5 pm, about 2 pm, about

2.5 pm, about 3 pm, about 3.5 pm, about 4 pm, about 4.5 pm, about 5 pm, about 5.5 pm, about 6 pm, about 6.5 pm, about 7 pm, about 7.5 pm, about 8 pm, about 8.5 pm, about 9 pm, about

9.5 pm, or about 10 pm, including all ranges and values therebetween. In some embodiments, the primary precipitates have an average diameter ranging from about 0.5 to about 1.5 pm. In some embodiments, the primary precipitates have an average diameter ranging from about 0.1 to about 1.5 pm. In some embodiments, the primary precipitates are Al-X primary precipitates. In some embodiments, X is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Y, La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu. In some embodiments, X is Zr. In some embodiments, the primary precipitates are AbZr primary precipitates. In some embodiments, the Al-X nano- scale precipitates have an average diameter ranging from about 1 to about 100 nm, e.g., about 1 nm, about 2 nm, about 4 nm, about 6 nm, about 8 nm, about 10 nm, about 12 nm, about 14 nm, about 16 nm, about 18 nm, about 20 nm, about 22 nm, about 24 nm, about 26 nm, about 28 nm, about 30 nm, about 32 nm, about 34 nm, about 36 nm, about 38 nm, about 40 nm, about 42 nm, about 44 nm, about 46 nm, about 48 nm, about 50 nm, about 52 nm, about 54 nm, about 56 nm, about 58 nm, about 60 nm, about 62 nm, about 64 nm, about 66 nm, about 68 nm, about 70 nm, about 72 nm, about 74 nm, about 76 nm, about 78 nm, about 80 nm, about 82 nm, about 84 nm, about 86 nm, about 88 nm, about 90 nm, about 92 nm, about 94 nm, about 96 nm, about 98 nm, or about 100 nm, including all ranges and values therebetween. In some embodiments, the Al-X nano-scale precipitates have an average diameter ranging from about 3 to about 50 nm. In some embodiments, the AbZr nano-scale precipitates have an average diameter ranging from about 3 to about 20 nm. In some embodiments, the Al-X nano-scale precipitates have an average diameter ranging from about 3 to about 10 nm. In some embodiments, X is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Y, La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu. In some embodiments, the nano-scale precipitates are AbZr nano-scale precipitates.

[1132] In some embodiments, the heat-aging the net-shape component, the near-net-shape component, or the component extruded from the billet is for a time of about 1 h, about 2 h, about 3 h, about 4 h, about 5 h, about 6 h, about 7 h, about 8 h, about 9 h, about 10 h, about 11 h, about 12 h, about 13 h, about 14 h, about 15 h, about 16 h, about 17 h, about 18 h, about 19 h, about 20 h, about 21 h, about 22 h, about 23 h, about 24 h, about 25 h, about 26 h, about 27 h, about 28 h, about 29 h, about 30 h, about 31 h, about 32 h, about 33 h, about 34 h, about 35 h, about 36 h, about 37 h, about 38 h, about 39 h, about 40 h, about 41 h, about 42 h, about 43 h, about 44 h, about 45 h, about 46 h, about 47 h, or about 48 h, including all ranges and values therebetween. In some embodiments, the heat-aging of step is for a time of about 1 h to about 10 h. In some embodiments, the heat-aging of step is for a time of about 1 h to about 5 h. In some embodiments, the heat-aging of step is for a time of about 1 h to about 3 h. In some embodiments, the heat-aging of step is for a time of about 5 h to about 20 h. In some embodiments, the heat-aging of step is for a time of about 5 h to about 15 h. In some embodiments, the heat-aging of step is for a time of about 5 h to about 10 h.

[1133] In some embodiments, an aluminum alloy component is manufactured by fabricating a ribbon, chips, or a powder from any of the 7000-series aluminum alloys using a rapid solidification process; and then using the ribbon, chips, or powder in a powder metallurgy process to manufacture a net-shape component, a near-net-shape component, or a component extruded from a billet. In some embodiments, the method further comprises heat-treating the net-shape component, the near-net-shape component, or the component extruded from the billet at a temperature of about 400°C to about 480°C for a time of about 0.25 hours to about 6 hours; and heat-aging the component at a temperature of about l00°C to about l80°C for a time of about 1 hour to about 48 hours, to achieve a simultaneous dispersion of fine-scale ZmMg precipitates, primary precipitates having an average diameter of about 0.1 to about 10 pm, and Al-X nano-scale precipitates having an average diameter of about 1 to about 100 nm, and resulting in the component having a strength which is at least as great as that of a component conventionally manufactured from a conventional 7000-series aluminum alloy. In some embodiments, X is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Y, La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu. In some embodiments, X is Zr.

[1134] In some embodiments, an aluminum alloy component is manufactured by fabricating a powder from any of the 7000-series aluminum alloys using a rapid solidification process; and then using the powder in an additive manufacturing process to manufacture a net- shape component or a near-net-shape component. In some embodiments, the method further comprises heat-treating the net-shape component or the near-net-shape component at a temperature of about 400°C to about 480°C for a time of about 0.25 hours to about 6 hours; and then heat-aging the component at a temperature of about l00°C to about l80°C for a time of about 1 hour to about 48 hours, to achieve a simultaneous dispersion of fine-scale Z Mg precipitates, primary precipitates having an average diameter of about 0.1 to about 10 pm, and Al-X nano-scale precipitates having an average diameter of about 1 to about 100 nm, and resulting in the component having a strength which is at least as great as that of a component conventionally manufactured from a conventional 7000-series aluminum alloy. In some embodiments, X is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Y, La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu. In some embodiments, X is Zr.

[1135] In some embodiments, a method to repair or to form a protective coating on a component made from an aluminum or a magnesium alloy is provided, the method comprising subjecting an aluminum alloy powder as disclosed herein to a cold spray process, a thermal spray process, a laser-assisted cold spray process, or a laser cladding process; and disposing the processed powder on a surface of the component made from an aluminum alloy; thereby repairing or forming a protective coating on the component.

[1136] In some embodiments, a method to repair or to form a protective coating on a component made from an aluminum alloy is provided, the method comprising subjecting an aluminum alloy powder as disclosed herein to a cold spray process, a thermal spray process, a laser-assisted cold spray process, or a laser cladding process; and disposing the processed powder on a surface of the component made from an aluminum alloy; thereby repairing or forming a protective coating on the component.

[1137] In some embodiments, the method to repair or to form a protective coating, further comprises heat-aging the component made from an aluminum alloy at a temperature of about l00°C to about l80°C for a time of about 1 hour to about 48 hours. In some embodiments, prior to the heat-aging step, the component made from an aluminum alloy component of the present disclosure is heat treated at a temperature of about 400°C to about 480°C for a time of about 0.25 hours to about 6 hours.

[1138] From the foregoing, it will be understood that numerous modifications and variations can be effectuated without departing from the true spirit and scope of the novel concepts of the present disclosure. It is to be understood that no limitation with respect to the specific embodiments illustrated and described is intended or should be inferred.

Examples

Example 1

[1139] The chemical compositions and physical properties of Example alloy 1 (Zr-free) and the New alloy comprising Zr are compared in Table 2. The two alloys were both fabricated by melt spinning, followed by consolidating into a billet by hot pressing, and then extruding into a profile. Although both compositions have similar hardness after melt spinning, the alloy displays an age-hardening response during the heat treatment whereas the example alloy does not (Fig. 5). Without being bound by any particular theory, it is believed that this is the effect of Al-X precipitates forming during this thermal process. Both alloys respond to a second thermal aging where conventional Z Mg precipitates are formed, and the alloy retains the same incremental increase in hardness over the example alloy.

[1140] The addition of Zr allows the alloy to reach a higher maximum strength and improves its thermal stability by maintaining fine grains during a high temperature heat treatment, as shown in Fig. 3 (example alloy 1), Fig. 4, and Fig. 6.

[1141] The scanning electron micrograph of the melt-spun ribbon of example alloy 1 supports the above findings, and shows that grains are large (Fig. 1). In contrast, the scanning electron micrograph of the alloy from Table 2 shows that grains are highly refined, with multiple grains contained with the ribbon (Fig. 2). Thus, while the conventional alloy exhibits the uninhibited grain growth that ultimately leads to liquation cracking and hot cracking when the material is welded or subjected to additive manufacturing, the aluminum alloy is free from such characteristics. Consequently the alloy is stronger and more thermally stable.

Table 2

Knoop Microhardness (MPa)

[Zn] [Mg] [Cu] [Zr] _{Solution Artifldai}

Alloy

wt ^. /o wt ^. /o wt ^. /o wt ^. /o \ _s _r _\ I _c| t Spun Treated Aging

(450 °C, 1 h ) (120 °C, 10 h)

Example alloy 1 11 2.5 1 0.0 1,560 1,620 2,300

New alloy 11 2.5 1 1.5 1,650 2,060 2,850

Example 2

[1142] Attempts have been made to fabricate conventional 7000-series aluminum alloys by additive manufacturing processes, namely selective laser melting (SLM). Due to hot cracking issues these attempts were largely unsuccessful (example alloy 1) [refer to HRL, Sistiaga publications]. Towards this end, some researchers have worked to develop custom 7000-series alloys tailored for the AM process. One example is an Al-Zn-Mg alloy with large additions of Sc (example alloy 3) [Zhou]

[1143] Another solution is to blend the aluminum alloy powder with a second powder which serves as an inoculant to nucleate fine grains during solidification (example alloy 2) [HRL] While technically feasible, this approach adds complexity and cost.

[1144] The alloy has solved the hot cracking issue during printing without using expensive elements like scandium, while at the same time improving the strength over the other examples of 3D printed 7000-series aluminum.

[1145] Table 3 lists properties of 7000-series aluminum alloys fabricated by selective laser melting of gas-atomized powder. In all cases, the 3D printed material has been subject to a T6 heat treatment involving a solutionizing step at ~450-480°C followed by an artificial aging step at ~l20°C.

Table 3

*Zr added in the form of Zr¾ to powder, not alloyed.

• [HRL] Martin, John H., Brennan D. Yahata, Jacob M. Hundley, Justin A. Mayer, Tobias A. Schaedler, and Tresa M. Pollock. "3D printing of high-strength aluminium alloys." Nature 549, no. 7672 (2017): 365.

• [Sistiaga] Montero-Sistiaga, Maria L., Raya Mertens, Bey Vrancken, Xiebin Wang, Brecht Van Hooreweder, Jean-Pierre Kruth, and Jan Van Humbeeck. "Changing the ahoy composition of A17075 for better processability by selective laser melting." Journal of Materials Processing Technology 238 (2016): 437-445. [Zhou] Zhou, Le, Hao Pan, Holden Hyer, Sharon Park, Yuanli Bai, Brandon McWilliams, Kyu Cho, and Yongho Sohn. "Microstructure and tensile property of a novel AIZnMgScZr alloy additively manufactured by gas atomization and laser powder bed fusion." Scripta Materialia 158 (2019): 24-28

Example 3 :

[1146] 7000-series alloys can be fabricated by rapid solidification processes and consolidated by conventional powder processes. One such alloy is commercially produced AA7034, in which melt spun ribbons are chopped into chips, consolidated into a billet by hot pressing, and extruded into a profile. In this example, a Cu-free 7000-series alloy is produced into powder by gas-atomization (a rapid solidification process), consolidated into a billet by hot pressing, and extruded into a profile (Process 1). Also in this example is a Cu-free 7000- series alloy which is produced into a powder by gas atomization and directly extruded into a profile without an intermediate consolidation step (Process 2).

[1147] Although the mechanical properties are similar to an alloy which is commercially produced, it is advantageous to eliminate copper in the alloy chemistry, which improves weldability and corrosion resistance. The addition of zirconium is also advantageous for improving weldability and thermal stability.

[1148] Mechanical properties of rapid solidification and extruded 7000-series alloys are provided in Table 4. In all cases, the extruded material has been subject to a T6 heat treatment involving a solutionizing step at ~450-480°C followed by an artificial aging step at ~l20°C.

Table 4