FROM THE SAME

FIEUD OF THE INVENTION

[0001] The present disclosure relates to methods for welding aluminum alloys and products made from the same.

BACKGROUND

[0002] Aluminum alloys are used in a variety of industries including marine, defense, automotive, railroad, transportation, aerospace, liquefied natural gas, and oil and gas, among others. Common to all of these industries is the need to weld parts together with fusion based and/or solid state based welding processes.

SUMMARY OF THE DISCUOSURE

[0003] Broadly, the present disclosure relates to methods for welding aluminum alloys and products made from the same. The methods described herein generally realize weldments having improved properties. For instance, the welded products described herein may realize weldments having improved strength, toughness, and/or ductility, among others. The new methods generally include abutting two aluminum alloy components, fusion welding a first zone using a first weld filler wire, and then fusion welding a second zone using a second weld filler wire that is different from the first weld filler wire. The products made from the methods described herein generally comprise a fusion welded portion disposed between a first base portion and a second base portion. The welded portion generally is comprised of a first weld zone, a second weld zone, and a middle weld zone. Additional details are provided below.

[0004] As used herein,“fusion welding” means the melting together of filler metal and base metal, or of base metal only, to produce a weld. Fusion welding of components (e.g., plates, extrusions, sheets, forgings, castings) may be performed using, for instance, gas metal arc welding and gas tungsten arc welding, among others.

[0005] As used herein, a“weld” is a region formed by the joining of at least two materials. For instance, a weld may be formed via fusion welding.

[0006] As used herein,“weld filler wire” means a wire or other suitable configuration that is capable of fusion with another material. For instance, weld filler wires may be used in fusion welding (defined above), where the weld filler wire fuses with a first material and/or a second material, thereby creating a weld. Furthermore, a weld filler wire may be used for repairing defects. For instance, surface defects may be repaired using weld filler wire (e.g., in accordance with U.S. Patent Pub. No. 20100276108). In one embodiment a method comprises (a) locating a surface defect of an aluminum alloy, where the surface defect has a first volume, where the surface defect is at least partially surrounded by an original volume, where the aluminum alloy includes the original volume, and then (b) repairing the surface defect, where the repairing comprises fusion welding at least a portion of the original volume to produce a repaired volume, where the fusion welding comprises (i) first fusion welding a first zone using a first weld filler wire, and then (ii) second fusion welding a second zone using a second weld filler wire, where the second weld filler wire is different from the first weld filler wire, and where the repaired volume includes the first volume of the surface defect and at least a portion of the original volume. After the repairing, the repaired portion may be mechanically or chemically texturized (e.g., via mechanical denting, chemical etching, and combinations thereof). The aluminum alloy may be any of the first and/or second aluminum alloy component compositions described herein. The first and second weld filler wires may similarly be of any of the first and second weld filler wire compositions described herein. In one embodiment, an aluminum alloy is in the form of a mold block.

[0007] The figures constitute a part of this specification and include illustrative embodiments of the present disclosure and illustrate various objects and features thereof. In addition, any measurements, specifications and the like shown in the figures are intended to be illustrative, and not restrictive. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.

[0008] Among those benefits and improvements that have been disclosed, other objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying figures. Detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely illustrative of the invention that may be embodied in various forms. In addition, each of the examples given in connection with the various embodiments of the invention is intended to be illustrative, and not restrictive.

[0009] Throughout the specification and claims, the following terms take the meanings explicitly associated herein, unless the context clearly dictates otherwise. The phrases“in one embodiment” and“in some embodiments” as used herein do not necessarily refer to the same embodiment(s), though it may. Furthermore, the phrases“in another embodiment” and “in some other embodiments” as used herein do not necessarily refer to a different embodiment, although it may. Thus, as described below, various embodiments of the invention may be readily combined, without departing from the scope or spirit of the invention.

[0010] In addition, as used herein, the term "or" is an inclusive "or" operator, and is equivalent to the term "and/or," unless the context clearly dictates otherwise. The term "based on" is not exclusive and allows for being based on additional factors not described, unless the context clearly dictates otherwise. In addition, throughout the specification, the meaning of "a," "an," and "the" include plural references, unless the context clearly dictates otherwise. The meaning of "in" includes "in" and "on", unless the context clearly dictates otherwise.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] FIG. la is an embodiment of a method for welding aluminum alloys.

[0012] FIG. lb is an embodiment of a method for welding aluminum alloys.

[0013] FIG. 2 is a schematic diagram of a welded alloy product.

[0014] FIG. 3 is a schematic diagram of a welded alloy product.

[0015] FIG. 4a is a schematic diagram illustrating one embodiment of an abutment of aluminum alloy components used for preparing the weldments described in the Examples.

[0016] FIG. 4b is a schematic diagram illustrating one embodiment of weldments described in the Examples.

[0017] FIG. 4c is an optical micrograph of weld 2 from the Examples.

[0018] FIG. 4d is an optical micrograph of weld 3 from the Examples.

[0019] FIG. 5a is a schematic diagram illustrating preparation of a Charpy impact V- notch test sample per the Examples.

[0020] FIG. 5b is a schematic diagram illustrating the Charpy impact V-notch test sample used for the Charpy impact V-notch tests per the Examples.

DETAILED DESCRIPTION

i. Methods

[0021] With reference to FIG. la, the new methods for welding aluminum alloys described herein generally include abutting a first aluminum alloy component against a second aluminum alloy component (10), fusion welding a first zone (20), and then fusion welding a second zone (30). In a particular embodiment, and with reference now to FIG. lb, a new method may include abutting a first aluminum alloy component against a second aluminum alloy component (10), where at least one of the first aluminum alloy component and the second aluminum alloy component is one of a 2xxx aluminum alloy or a 7xxx aluminum alloy (12), fusion welding a first zone using a first weld filler wire (20), where the first weld filler wire is one of a 2xxx aluminum alloy or a 7xxx aluminum alloy (22), and then fusion welding a second zone using a second weld filler wire (30), where the second weld filler wire is different from the first weld filler wire. In this regard, due to the second fusion welding, the second zone may be adjacent to and integral with the first zone. Furthermore, due to the first fusion welding, the first zone may be adjacent to and integral with the first aluminum alloy component and the second aluminum alloy component. In some embodiments, the first aluminum alloy component and the second aluminum alloy component are the same aluminum alloy (e.g., the same 7xxx aluminum alloy or the same 2xxx aluminum alloy). In other embodiments, the first aluminum alloy component and the second aluminum alloy component are different aluminum alloys, the first aluminum alloy component having a first composition, the second aluminum alloy component having a second composition, and with the first composition being different than the second composition.

[0022] As used herein, “aluminum alloy” means an alloy having aluminum as the predominate alloying element and at least one other element in solid solution with the aluminum. Aluminum alloy components and first weld filler wires that may be used with the methods herein include, for instance, those made from the 2xxx and 7xxx aluminum alloys. Second weld filler wires that may be used include, for instance, those made from the 2xxx, 4xxx, 5xxx, and 7xxx aluminum alloys. Thus, aluminum alloys that may be used with the methods described herein include the 2xxx, 4xxx, 5xxx, and 7xxx aluminum alloys. Definitions of 2xxx, 4xxx, 5xxx, and 7xxx aluminum alloy are per the document “International Alloy Designations and Chemical Composition Limits for Wrought Aluminum and Wrought Aluminum Alloys,” January 2015, published by the Aluminum Association, a.k.a.“the Teal Sheets.”

[0023] In one embodiment, a 2xxx aluminum alloy comprises from 2.0 to 7.0 wt. % Cu. In one embodiment, a 2xxx aluminum alloy comprises from 0.1 to 2.0 wt. % Mg. In one embodiment, a 2xxx aluminum alloy comprises up to 2.5 wt. % Li, or up to 3.0 wt. % Li. In one embodiment, a 4xxx aluminum alloy comprises from 0.8 to 13.5 wt. % Si. In one embodiment, a 4xxx aluminum alloy comprises from 0.1 to 2.0 wt. % Mg. In one embodiment, a 5xxx aluminum alloy comprises from 2.0 to 7.0 wt. % Mg. In one embodiment, a 5xxx aluminum alloy comprises at least 4.5 wt. % Mg. In one embodiment, a 7xxx aluminum alloy comprises from 2.0 to 12 wt. % Zn. In one embodiment, a 7xxx aluminum alloy comprises from 1.0 to 3.0 wt. % Mg. In one embodiment, a 7xxx aluminum alloy comprises from 1.0 to 4.0 wt. % Cu, or from 1.1 to 3.0 wt. % Cu. 7xxx aluminum alloys having at least 1.1 wt. % Cu are referred to herein as“high copper 7xxx aluminum alloys.” In another embodiment, a 7xxx aluminum alloy comprises from 0.25 to 1.0 wt. % Cu. In yet another embodiment, a 7xxx aluminum alloy comprises not greater than 0.25 wt. % Cu. Other suitable aluminum alloy compositions are provided below.

[0024] As noted above, at least one of the first aluminum alloy component and the second aluminum alloy component may be a 2xxx aluminum alloy or a 7xxx aluminum alloy. In some embodiments, at least one of the first aluminum alloy component and the second aluminum alloy component is a 7xxx aluminum alloy, such as any of the 7xxx aluminum alloys described above and herein. Non-limiting examples of 7xxx aluminum alloys that may be useful as the first and/or second aluminum alloy component include the 7085, 7185, 7285, 7065, 7055, 7155, 7255, 7040, 7140, 7050, 7150, 7250, 7136, 7081, 7181, 7099, 7199 and 7097 aluminum alloys, as defined by the Teal Sheets. In one embodiment, at least one of the first aluminum alloy component and the second aluminum alloy component comprises aluminum alloy 7085 or another high copper 7xxx aluminum alloy. In another embodiment, a 7xxx aluminum alloy component comprises one of a 7055, 7065, or 7085 aluminum alloy. Other suitable 7xxx aluminum alloys are provided herein.

[0025] Some 2xxx aluminum alloys components that may be useful in accordance with the welding methods described herein may be those having from 2.0 to 7.0 wt. % Cu, or from 2.0 to 6.0 wt. % Cu, and from 0.1 to 2.0 wt. % Mg, or from 0.1 to 1.5 wt. % Mg, or from 0.1 to 1.0 wt. % Mg, optionally with up to 2.5 or 3.0 wt. % Li, up to 1.0 wt. % Mn, and up to 1.0 wt. % Ag. Other suitable 2xxx aluminum alloys are provided herein.

[0026] As noted above, the first weld filler wire may be one of a 2xxx aluminum alloy or a 7xxx aluminum alloy. In one embodiment, the first weld filler wire comprises a 7xxx aluminum alloy. A 7xxx weld filler wire may be made from any of the 7xxx aluminum alloys described herein. In some embodiments, the first weld filler wire comprises a 7xxx aluminum alloy having from 6.0 to 9.0 wt. % Zn, from 2.3 to 2.7 wt. % Mg, and from 1.4 to 1.8 wt. % Cu. In one embodiment, a first weld filler wire comprises a 7xxx aluminum alloy having from 5.4 to 5.9 wt. % Zn, 2.75 to 3.25 wt. % Cu, and from 2.4 to 2.9 wt. % Mg. In some of these embodiments, the balance of the alloy is aluminum, incidental elements (e.g., grain refining elements; grain structure control elements), and impurities. In one embodiment, a first weld filler wire comprises a 7xxx aluminum alloy having from 6.0 to 9.0 wt. % Zn, from 2.3 to 2.7 wt. % Mg, from 1.4 to 1.8 wt. % Cu, up to 0.15 wt. % Fe, up to 0.15 wt. % Si, and from 0.05 to 0.20 wt. % Zr, the balance being aluminum, incidental elements, and impurities. In another embodiment, a first weld filler wire comprises a 7xxx aluminum alloy having from 5.4 to 5.9 wt. % Zn, from 2.4 to 2.9 wt. % Mg, from 2.75 to 3.25 wt. % Cu, up to 0.06 wt. % Si, up to 0.08 wt. % Fe, from 0.05 to 0.20 wt. % Zr, from 0.06 to 0.10 wt. % Ti, and from 0.015 to 0.025 wt. % B, the balance being aluminum, incidental elements, and impurities.

[0027] In one embodiment, the first weld filler wire comprises a 2xxx aluminum alloy. A 2xxx weld filler wire may be made from any of the 2xxx aluminum alloys described herein. In one embodiment, a first weld filler wire comprises a 2xxx aluminum alloy having from 5.0 to 6.5 wt. % Cu, from 2.0 to 3.0 wt. % Mg, and from 2.0 to 4.0 wt. % Zn. In some of these embodiments, the balance of the alloy is aluminum, incidental elements (e.g., grain refining elements; grain structure control elements), and impurities. In one embodiment, a first weld filler wire comprises a 2xxx aluminum alloy having from 5.0 to 6.5 wt. % Cu, from 2.0 to 3.0 wt. % Mg, from 2.0 to 4.0 wt. % Zn, up to 0.25 wt. % Si, up to 0.25 wt. % Fe, from 0.05 to 0.20 wt. % Ti, up to 0.10 wt. % B, and from 0.05 to 0.20 wt. % Zr, the balance being aluminum, incidental elements, and impurities.

[0028] As noted above, the second weld filler wire may be an aluminum alloy that is different from the first weld filler wire. For instance, the first weld filler wire may be a 2xxx aluminum alloy and the second weld filler wire may be a different 2xxx aluminum alloy, where the composition of the second weld filler alloy is different from the first weld filler alloy. Similarly, the first weld filler wire may be a 7xxx aluminum alloy and the second weld filler wire may be a different 7xxx aluminum alloy, where the composition of the second weld filler alloy is different from the first weld filler alloy.

[0029] In one embodiment, the second weld filler wire is one of a 2xxx aluminum alloy, a 4xxx aluminum alloy, a 5xxx aluminum alloy, or a 7xxx aluminum alloy. In one embodiment, a second weld filler wire comprises a 2xxx aluminum alloy. In one embodiment, a second weld filler wire comprises a 4xxx aluminum alloy. In one embodiment, the second weld filler wire comprises aluminum alloy 4043 or similar. In one embodiment, a second weld filler wire comprises a 5xxx aluminum alloy. In one embodiment, a second weld filler wire comprises a 5xxx aluminum alloy having at least 4.5 wt. % Mg. In one embodiment, a second weld filler wire comprises a 5xxx aluminum alloy having from 5.6 to 8.0 wt. % Mg. In another embodiment, a second weld filler wire comprises a 5xxx aluminum alloy having from 5.6 to 8.0 wt. % Mg and from 0.05 to 3.5 wt. % Zn. In one embodiment, a second weld filler wire comprises a 5xxx aluminum alloy having from 5.3 to 6.2 wt. % Mg, from 3.5 to 4.5 wt. % Cu, and from 0.7 to 1.3 wt. % Zn. In some of these embodiments, the balance of the alloy is aluminum, incidental elements (e.g., grain refining elements; grain structure control elements), and impurities. In one embodiment, the second weld filler wire comprises aluminum alloy 5556 or similar. In one embodiment, a second weld filler wire comprises a 7xxx aluminum alloy.

[0030] In one embodiment, at least one of the first aluminum alloy component and the second aluminum alloy component comprises a 7xxx aluminum alloy, the first weld filler wire comprises a 7xxx aluminum alloy, and the second weld filler wire comprises a 5xxx aluminum alloy. In one embodiment, at least one of the first aluminum alloy component and the second aluminum alloy component comprises aluminum alloy 7085 or another high copper 7xxx aluminum alloy, the first weld filler wire comprises a 7xxx aluminum alloy having from 6.0 to 9.0 wt. % Zn, from 2.3 to 2.7 wt. % Mg, and from 1.4 to 1.8 wt. % Cu, and the second weld filler wire comprises a 5xxx aluminum alloy. In one embodiment, at least one of the first aluminum alloy component and the second aluminum alloy component comprises aluminum alloy 7085 or another high copper 7xxx aluminum alloy, the first weld filler wire comprises a 7xxx aluminum alloy having from 5.4 to 5.9 wt. % Zn, from 2.75 to 3.25 wt. % Cu, from 2.4 to 2.9 wt. % Mg, and the second weld filler wire comprises a 5xxx aluminum alloy. In some of these embodiments, the second weld filler wire is aluminum alloy 5556 or similar.

[0031] In one embodiment, at least one of the first aluminum alloy component and the second aluminum alloy component comprises a 2xxx or a 7xxx aluminum alloy, the first weld filler wire comprises a 2xxx aluminum alloy, and the second weld filler wire comprises a 5xxx aluminum alloy. In one embodiment, at least one of the first aluminum alloy component and the second aluminum alloy component comprises aluminum alloy 7085 or another high copper 7xxx aluminum alloy, the first weld filler wire comprises a 2xxx aluminum alloy having from 5.0 to 6.5 wt. % Cu, from 2.0 to 3.0 wt. % Mg, and from 2.0 to 4.0 wt. % Zn, and the second weld filler wire comprises a 5xxx aluminum alloy. In some of these embodiments, the second weld filler wire is aluminum alloy 5556 or similar. ii. Products

[0032] The methods described herein may be used to produce welded alloy products having one or more weldments having improved properties, such as having improved strength, toughness, and/or ductility, among others. In one embodiment, a welded alloy product realizes at least two of an improved strength, an improved toughness, and an improved ductility. In another embodiment, a welded alloy product realizes an improved strength, an improved toughness, and an improved ductility. As described in greater detail below, a welded alloy product made in accordance with one or more of the methods described herein generally comprises a first base portion, a second base portion, and a fusion welded portion disposed between the first base portion and the second base portion.

[0033] With reference now to FIG. 2, one embodiment of a welded alloy product (200) is shown. This type of weldment in the welded alloy product (200) is commonly referred to as a single-V butt weld. In the illustrated embodiment, the welded alloy product (200) comprises a first base portion (201), a second base portion (202), and a fusion welded portion (250). The fusion welded portion (250) comprises a first weld zone (210), a second weld zone (212), and a middle weld zone (220). As illustrated, the fusion welded portion (250) is disposed between the first base portion (201) and the second base portion (202). Further, the illustrated embodiment of FIG. 2 shows a first weld zone (210) that is adjacent to and integral with the first base portion (201), and a second weld zone (212) that is adjacent to and integral with the second base portion (202). However, as illustrated, the first weld zone (210) is segregated from the second weld zone (220), as opposed to being adjacent to and integral with the second weld zone (see FIG. 3). The first weld zone (210) and/or second weld zone (212) may be produced via fusion welding of a first weld filler wire. Further, the middle weld zone (220) may be produced via fusion welding of a second weld filler wire. An example of a weldment of this type is given in the below Examples. The first weld zone (210) may be produced by performing one or more fusion weld passes on the first aluminum base portion (201). Similarly, the second weld zone (212) may be produced by performing one or more weld passes on the second base portion (202). Furthermore, the middle weld zone (220) may be produced by performing one or more weld passes between the first base portion (201) and second base portion (202).

[0034] With reference now to FIG. 3, an embodiment of a welded alloy product (300) is shown. This type of weldment in the welded alloy product (300) is commonly referred to as a single-V butt weld. In the illustrated embodiment, the welded alloy product (300) comprises a first base portion (301), a second base portion (302), and a fusion welded portion (350). The fusion welded portion (350) comprises a first weld zone (310), a second weld zone (312), and a middle weld zone (320). As illustrated in this embodiment, the first weld zone (310) is adjacent to and integral with the second weld zone (312), generally forming a single weld zone. The first weld zone (310) and/or second weld zone (312) may be produced by first performing one or more weld passes on the first base portion (301) and second base portion (302), respectively, followed by one or more passes between the first base portion (301) and second base portion (302). The first weld zone (310) and second weld zone (320) may be produced via fusion welding with a first weld filler wire. The middle weld zone (320) may be produced via fusion welding with a second weld filler wire.

[0035] With reference now to FIGS. 2 and 3, in one embodiment, at least one of the first base portion (201, 301) and the second base portion (202, 302) comprises a 2xxx aluminum alloy or a 7xxx aluminum alloy. The first base portion (201, 301) and/or second base portion (202, 302) may be any one of the 2xxx aluminum alloys or 7xxx aluminum alloys described herein as being suitable as a first and/or second aluminum alloy component. Furthermore, at least one of the first weld zone (210, 310) and second weld (212, 312) zone may comprise one of a 2xxx or 7xxx aluminum alloy. For instance, the first weld zone (210, 310) and second weld zone (212, 312) may be produced using a first weld filler wire comprising a 2xxx or 7xxx aluminum alloy, such as any of the 2xxx or 7xxx aluminum alloys described herein as being suitable as a first weld filler wire. The middle zone (220, 320) generally comprises an aluminum alloy having a composition different than the first weld zone (210, 310) and the second weld zone (212, 312).

[0036] In one embodiment, a welded alloy product is a crack-free product. As used herein,“crack-free product” means a product that is sufficiently free of cracks such that it can be used for its intended, end-use purpose. The determination of whether a welded alloy product is“crack-free” may be made by any suitable method, such as, by visual inspection, dye penetrant inspection and/or by non-destructive test methods. In some embodiments, the non-destructive test method is an ultrasonic inspection. In some embodiments, the non destructive test method is a computed topography scan (“CT scan”) inspection (e.g., by measuring density differences within the product). In one embodiment, a welded alloy product is determined to be crack-free by visual inspection. In another embodiment, a welded alloy product is determined to be crack-free by dye penetrant inspection.

[0037] In one embodiment, at least one of the first weld zone and the second weld zone comprises a 7xxx aluminum alloy, such as any of the 7xxx aluminum alloys described herein. In one embodiment, at least one of the first weld zone and the second weld zone comprises a 7xxx aluminum alloy having from 6.0 to 9.0 wt. % Zn, from 2.3 to 2.7 wt. % Mg, and from 1.4 to 1.8 wt. % Cu. In one embodiment, at least one of the first weld zone and the second weld zone comprises a 7xxx aluminum alloy having from 5.4 to 5.9 wt. % Zn, from 2.75 to 3.25 wt. % Cu, from 2.4 to 2.9 wt. % Mg. In one embodiment, at least one of the first weld zone and the second weld zone comprises a 2xxx aluminum alloy. In one embodiment, at least one of the first weld zone and the second weld zone comprises a 2xxx aluminum alloy having from 5.0 to 6.5 wt. % Cu, from 2.0 to 3.0 wt. % Mg, and from 2.0 to 4.0 wt. % Zn.

[0038] The middle weld zone (220, 320) may comprise a 2xxx aluminum alloy, a 4xxx aluminum alloy, a 5xxx aluminum alloy, or a 7xxx aluminum alloy. In one embodiment, a middle weld zone comprises a 2xxx aluminum alloy. In one embodiment, a middle weld zone comprises a 4xxx aluminum alloy. In one embodiment, a middle weld zone comprises aluminum alloy 4043 or similar. In one embodiment, a middle weld zone comprises a 5xxx aluminum alloy. In one embodiment, a middle weld zone comprises a 5xxx aluminum alloy having at least 4.5 wt. % Mg. In one embodiment, a middle weld zone comprises a 5xxx aluminum alloy having from 5.6 to 8.0 wt. % Mg. In one embodiment, a middle weld zone comprises a 5xxx aluminum alloy having from 5.6 to 8.0 wt. % Mg, and from 0.05 to 3.5 wt. % Zn. In one embodiment, a middle weld zone comprises a 5xxx aluminum alloy having from 5.3 to 6.2 wt. % Mg, from 3.5 to 4.5 wt. % Cu, and from 0.7 to 1.3 wt. % Zn. In one embodiment, a middle weld zone comprises aluminum alloy 5556 or similar. In one embodiment, a middle weld zone comprises a 7xxx aluminum alloy, such as any of the 7xxx aluminum alloys described herein.

[0039] In some embodiments, a welded alloy product comprises a first base portion comprising a 7xxx aluminum alloy, where the first weld zone comprises more copper than the first base portion. In one embodiment, a first weld zone comprises at least 0.25 wt. % more copper than the first base portion. In another embodiment, a first weld zone comprises at least 0.50 wt. % more copper than the first base portion. In yet another embodiment, a first weld zone comprises at least 0.75 wt. % more copper than the first base portion. In another embodiment, a first weld zone comprises at least 1.0 wt. % more copper than the first base portion.

[0040] In some embodiments, a welded alloy product comprises a first base portion comprising a 7xxx aluminum alloy, where the first weld zone comprises more magnesium than the first base portion. In one embodiment, a first weld zone comprises at least 0.25 wt. % more magnesium than the first base portion. In another embodiment, a first weld zone comprises at least 0.50 wt. % more magnesium than the first base portion.

[0041] In some embodiments, a welded alloy product comprises a first base portion comprising a 2xxx aluminum alloy, where the first weld zone comprises more zinc than the first base portion. In one embodiment, a first weld zone comprises at least 0.25 wt. % more zinc than the first base portion. In another embodiment, a first weld zone comprises at least 0.50 wt. % more zinc than the first base portion. In yet another embodiment, a first weld zone comprises at least 0.75 wt. % more zinc than the first base portion. In another embodiment, a first weld zone comprises at least 1.0 wt. % more zinc than the first base portion.

[0042] In one embodiment, a welded alloy product comprises (a) a first base portion, (b) a second base portion, where at least one of the first base portion and second base portion is a 7xxx aluminum alloy, and (c) a fusion welded portion comprising a first weld zone, a second weld zone, and a middle weld zone, where at least one of the first weld zone and second weld zone comprises a 7xxx aluminum alloy, and where the middle weld zone comprises a 5xxx aluminum alloy. In one embodiment, at least one of the first base portion and the second base portion is aluminum alloy 7085 or another high copper 7xxx aluminum alloy, at least one of the first weld zone and the second weld zone comprises a 7xxx aluminum alloy having from 6.0 to 9.0 wt. % Zn, from 2.3 to 2.7 wt. % Mg, and from 1.4 to 1.8 wt. % Cu, and the middle weld zone comprises a 5xxx aluminum alloy. In another embodiment, at least one of the first base portion and second base portion is aluminum alloy 7085 or another high copper 7xxx aluminum alloy, at least one of the first weld zone and the second weld zone comprises a 7xxx aluminum alloy having from 5.4 to 5.9 wt. % Zn, from 2.75 to 3.25 wt. % Cu, from 2.4 to 2.9 wt. % Mg, and the middle weld zone comprises a 5xxx aluminum alloy. In some of these embodiments, the middle weld zone comprises aluminum alloy 5556 or similar.

[0043] In one embodiment, a welded alloy product comprises (a) a first base portion, (b) a second base portion, and (c) a fusion welded portion comprising a first weld zone, a second weld zone, and a middle weld zone, where at least one of the first base portion and the second base portion is a 7xxx aluminum alloy, where at least one of the first weld zone and the second weld zone comprises a 2xxx aluminum alloy, and where the middle weld zone comprises a 5xxx aluminum alloy. In one embodiment, at least one of the first base portion and the second base portion is aluminum alloy 7085 or another high copper 7xxx aluminum alloy, at least one of the first weld zone and the second weld zone comprises a 2xxx aluminum alloy having from 5.0 to 6.5 wt. % Cu, from 2.0 to 3.0 wt. % Mg, and from 2.0 to 4.0 wt. % Zn, and the middle weld zone comprises a 5xxx aluminum alloy. In some of these embodiments, the middle weld zone comprises aluminum alloy 5556 or similar.

Examples

[0044] Three welded joints were prepared in accordance with the schematic representation given in FIGS. 4a and 4b. That is, a first aluminum alloy component (401) was abutted to a second aluminum alloy component (402), and a weldment (410) was formed between the aluminum alloy components (401, 402). For all three welded joints, aluminum alloy 7085 was used for the first aluminum alloy component (401) and second aluminum alloy component (402). The welded joints were prepared with commercial weld filler wire aluminum alloy 5556 and a 7xxx weld filler wire (“Alloy 1”). Nominal compositions of the 7085 alloy, the 5556 alloy, and Alloy 1 are given in Table 1, below.

Table 1: Nominal Aluminum Alloy Compositions (in wt. %)

[0045] Prior to welding, the aluminum alloy components (401, 402) were machined from a 1.0 inch thick 7085 rolled plate that was saw cut beveled at a 37.5 degree angle. The aluminum alloy component (401, 402) surfaces to be welded were then wiped with acetone, filed, and then wire brushed with a stainless steel brush. Dimensions of the aluminum alloy component and the resulting welded joints are given in FIGS. 4a and 4b.

[0046] The weldments were produced using a gas tungsten arc with a 0.187 inch diameter zirconia tungsten electrode. Furthermore, the weldments were produced using a shielding gas consisting of 75% argon and 25% helium (by volume) at a flowrate of 40 cubic feet per hour. Between each welding pass, welded zones were brushed with a stainless steel wire brush. The welded zones were held at a temperature at or below l20°F between passes. Weld filler wires used for producing the welds included (1) a 0.125 inch diameter wire of commercial 5556 aluminum alloy, and (2) a 0.062 inch diameter wire of Alloy 1. The three welded joints were prepared in accordance with the following methods:

Method 1

[0047] The first welded joint (“Weld 1”) was prepared using only the Alloy 1 weld filler wire. A single weld zone was prepared using a total number of 7 passes using the Alloy 1 weld filler wire. Method 2

[0048] The second welded joint (“Weld 2”) was prepared using a method in accordance with that shown by FIG. 2 and described above in the specification. For method 2, the weld was prepared by fusion welding a first zone using the Alloy 1 filler wire, and fusion welding a second zone using the 5556 aluminum alloy weld filler wire. The first weld zone was produced by performing 3 weld passes on the aluminum alloy component surfaces on each side of the weld joint. The second weld zone was produced by performing 7 weld passes between the aluminum alloy components. An optical micrograph of a cross-section of Weld 2 is given in FIG. 4c.

Method 3

[0049] The third welded joint (“Weld 3”) was prepared using a method in accordance with that shown by FIG. 3 and described above in the specification. For method 3, the weld was prepared by fusion welding a first zone using the Alloy 1 weld filler wire, and fusion welding a second zone using the 5556 aluminum alloy weld filler wire. The first weld zone was produced by performing 6 weld passes on the aluminum alloy component surfaces and weld joint. The second weld zone was produced by performing 3 weld passes between the aluminum alloy components to fill the weld joint. An optical micrograph of a cross-section of Weld 3 is given in FIG. 4d.

[0050] Following the production of the three weld joints, each welded joint was evaluated using the Charpy impact V-notch test, and in accordance with ASTM standard E23 entitled, “Standard Test Methods for Notched Bar Impact Testing of Metallic Materials”. With reference now to FIG. 5 a, preparation of the Charpy impact V-notch samples including removing the weld reinforcement zone (510) from the welded joint (500), and then machining a 10 mm x 10 mm x 55 mm sample from the welded joint (500) ( see FIG. 5b). The sample was machined from 1 mm ± 0.5 mm away from the upper edge (512) of the welded joint. FIG. 5b shows the 10 mm x 10 mm x 55 mm sample (550) used for the Charpy impact V-notch test. The V-notch (552) location used for the Charpy impact V- notch test was located on the root side (554) of the sample. Three samples of each weld were prepared and evaluated using the Charpy impact V-notch test. Results from the Charpy impact V-notch test are given in Table 2, below.

Table 2: Charpy Impact V-notch Test Results

[0051] The inventive welds (Weld 2 and Weld 3) showed a significant improvement over the non-inventive weld (Weld 1). Furthermore, as illustrated in the optical micrographs (FIGS. 4c and 4d), the inventive welds were crack-free. Thus, the inventive method produced welds having a significant advantage over the conventional method and weld filler wire (i.e., Weld 1).

[0052] Aspects of the invention will now be described with reference to the following numbered clauses:

Clause 1. A method comprising:

(i) abutting a first aluminum alloy component against a second aluminum alloy component, wherein at least one of the first aluminum alloy component and the second aluminum alloy component is one of a 2xxx aluminum alloy or a 7xxx aluminum alloy;

(ii) first fusion welding a first zone using a first weld filler wire, wherein the first weld filler wire is one of a 2xxx aluminum alloy or a 7xxx aluminum alloy;

wherein, due to the first fusion welding, the first zone is adjacent to and integral with the first aluminum alloy component and the second aluminum alloy component;

(iii) second fusion welding a second zone using a second weld filler wire, wherein the second weld filler wire is different from the first weld filler wire, wherein the first zone is adjacent to the second zone;

wherein, due to the second fusion welding, the second zone is adjacent to and integral with the first zone.

Clause 2. The method of clause 1, wherein at least one of the first aluminum alloy component and second aluminum alloy component is a 7xxx aluminum alloy.

Clause 3. The method of clause 1, wherein at least one of the first aluminum alloy component and second aluminum alloy component is a 2xxx aluminum alloy.

Clause 4. The method of any of the preceding clauses, wherein the first aluminum alloy component and second aluminum alloy component comprise the same aluminum alloy.

Clause 5. The method of any of the preceding clauses, wherein the first weld filler wire comprises a 7xxx aluminum alloy.

Clause 6. The method of clause 5, wherein the first weld filler wire comprises from 6.0 to 9.0 wt. % Zn, from 2.3 to 2.7 wt. % Mg, and from 1.4 to 1.8 wt. % Cu. Clause 7. The method of clause 5, wherein the first weld filler wire comprises from 5.4 to 5.9 wt. % Zn, from 2.75 to 3.25 wt. % Cu, and from 2.4 to 2.9 wt. % Mg.

Clause 8. The method of any of clauses 1-4, wherein the first weld filler wire comprises a 2xxx aluminum alloy.

Clause 9. The method of clause 8, wherein the first weld filler wire comprises from 5.0 to 6.5 wt. % Cu, from 2.0 to 3.0 wt. % Mg, and from 2.0 to 4.0 wt. % Zn.

Clause 10. The method of any of the preceding clauses, wherein the second weld filler wire comprises one of a 2xxx aluminum alloy, a 4xxx aluminum alloy, a 5xxx aluminum alloy, or a 7xxx aluminum alloy.

Clause 11. The method of clause 10, wherein the second weld filler wire comprises a 5xxx aluminum alloy having at least 4.5 wt. % Mg.

Clause 12. The method of clause 11, wherein the second weld filler wire comprises a 5xxx aluminum alloy having from 5.6 to 8.0 wt. % Mg.

Clause 13. The method of clause 12, wherein the second weld filler wire comprises from 0.05 to 3.5 wt. % Zn.

Clause 14. The method of clause 11, wherein the second weld filler wire comprises from 5.3 to 6.2 wt. % Mg, from 3.5 to 4.5 wt. % Cu, and from 0.7 to 1.3 wt. % Zn.

Clause 15. The method of clause 11, wherein the second weld filler wire comprises aluminum alloy 5556.

Clause 16. The method of clause 10, wherein the second weld filler wire comprises aluminum alloy 4043.

Clause 17. A welded alloy product comprising:

(a) a first base portion;

(b) a second base portion;

wherein at least one of the first base portion and the second base portion comprises a 2xxx aluminum alloy or a 7xxx aluminum alloy;

(c) a fusion welded portion disposed between the first base portion and the second base portion, the fusion welded portion comprising:

(i) a first weld zone adjacent to and integral with the first base portion;

(ii) a second weld zone adjacent to and integral with the second base portion; wherein at least one of the first weld zone and second weld zone comprises one of a 2xxx aluminum alloy or a 7xxx aluminum alloy;

(iii) a middle weld zone disposed between and integral with the first weld zone and the second zone; and wherein the middle zone comprises an aluminum alloy having a composition different than the first weld zone and the second weld zone. Clause 18. The welded alloy product of clause 17, wherein the first weld zone is adjacent to and integral with the second weld zone.

Clause 19. The welded alloy product of any of clauses 17-18, wherein at least one of the first weld zone and second weld zone comprises a 7xxx aluminum alloy.

Clause 20. The welded alloy product of clause 19, wherein at least one of the first weld zone and second weld zone comprises from 6.0 to 9.0 wt. % Zn, from 2.3 to 2.7 wt. % Mg, and from 1.4 to 1.8 wt. % Cu.

Clause 21. The welded alloy product of clause 19, wherein at least one of the first weld zone and second weld zone comprises from 5.4 to 5.9 wt. % Zn, from 2.75 to 3.25 wt. % Cu, and from 2.4 to 2.9 wt. % Mg.

Clause 22. The welded alloy product of any of clauses 17-18, wherein at least one of the first weld zone and second weld zone comprises a 2xxx aluminum alloy.

Clause 23. The welded alloy product of clause 22, wherein at least one of the first weld zone and second weld zone comprises from 5.0 to 6.5 wt. % Cu, from 2.0 to 3.0 wt. % Mg, and from 2.0 to 4.0 wt. % Zn.

Clause 24. The welded alloy product of any of clauses 17-23, wherein the middle weld zone comprises one of a 2xxx aluminum alloy, a 4xxx aluminum alloy, a 5xxx aluminum alloy, or a 7xxx aluminum alloy.

Clause 25. The welded alloy product of clause 24, wherein the middle weld zone comprises a 5xxx aluminum alloy having at least 4.5 wt. % Mg.

Clause 26. The welded alloy product of 25, wherein the middle weld zone comprises from 5.6 to 8.0 wt. % Mg.

Clause 27. The welded alloy product of clause 26, wherein the middle weld zone comprises from 0.05 to 3.5 wt. % Zn.

Clause 28. The welded alloy product of clause 24, wherein the middle weld zone comprises from 5.3 to 6.2 wt. % Mg, from 3.5 to 4.5 wt. % Cu, and from 0.7 to 1.3 wt. % Zn.

Clause 29. The welded alloy product of clause 24, wherein the middle weld zone comprises aluminum alloy 5556.

Clause 30. The welded alloy product of clause 24, wherein the middle weld zone comprises aluminum alloy 4043.

Clause 31. The welded alloy product of any of clauses 17-30, wherein the first base portion comprises a high copper 7xxx aluminum alloy, and wherein the first weld zone comprises more copper than the first base portion. Clause 32. The welded alloy product of clause 31, wherein the first weld zone comprises at least 0.25 wt. % more copper, or 0.50 wt. % more copper, or 0.75 wt. % more copper, or 1.0 wt. % more copper than the first base portion.

Clause 33. The welded alloy product of any of clauses 17-30, wherein the first base portion comprises a high copper 7xxx aluminum alloy, and wherein the first weld zone comprises more magnesium than the first base portion.

Clause 34. The welded alloy product of clause 33, wherein the first weld zone comprises at least 0.25 wt. % more magnesium or 0.50 wt. % more magnesium than the first base portion. Clause 35. The welded alloy product of any of clauses 17-30, wherein the first base portion comprises a 2xxx aluminum alloy, and wherein the first weld zone comprises more zinc than the first base portion.

Clause 36. The welded alloy product of clause 35, wherein the first weld zone comprises at least 1.0 wt. % more zinc, or 2.0 wt. % more zinc, or 2.5 wt. % more zinc than the first base portion.

Clause 37. The welded alloy product of any of clauses 17-36, wherein the welded alloy product is crack-free.

[0053] Other clauses based on any of the above paragraphs of the specification and the attached drawings are contemplated and apply to the present patent application.

[0054] While a number of embodiments of the present invention have been described, it is understood that these embodiments are illustrative only, and not restrictive, and that many modifications may become apparent to those of ordinary skill in the art. Further still, the various steps may be carried out in any desired order (and any desired steps may be added and/or any desired steps may be eliminated).