CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of and priority to U.S. Provisional Application

No. 62/949,286, filed on Dec. 17, 2019, which is hereby incorporated by reference in its entirety.

FIELD

[0002] The present disclosure relates to metallurgy generally and more specifically to metal alloy products that resist stress corrosion cracking and methods of making metal alloy products.

BACKGROUND

[0003] High-strength and durable aluminum alloys are desirable for use in a number of different applications. Magnesium in solid solution is effective in strengthening aluminum alloys, and magnesium-containing aluminum alloys are relatively inert because magnesium oxide that forms at the surface creates a barrier to corrosion. For example, 5xxx series aluminum alloys are generally considered relatively inert to seawater corrosion and thus are particularly useful in marine construction or offshore applications. 7xxx series aluminum alloys also demonstrate good corrosion resistance in most environments. Nonetheless, 5xxx series aluminum alloys containing relatively high content of magnesium (e.g., 3 wt. % or greater) as an alloying element, as well as 7xxx series aluminum alloys containing low or no copper and 7xxx series aluminum alloys or containing relatively high combined content of zinc, magnesium, and copper (e.g., 6 wt. % or greater), can experience stress corrosion cracking over time.

[0004] Stress corrosion cracking usually occurs at the grain boundaries where stress corrosion cracks may make a trans granular path, especially at the later stages when the failure is more mechanical than corrosive. The start of the cracks requires an indentation in the metal, such as a deep pit or an etched grain boundary. The growth of the cracks generally starts slow, but then transforms and becomes rapid. Roughly, about 70% to about 90% of the time to failure is for nucleation of the crack. Cracks can also be triggered when vacancies or dislocations pile up. [0005] Tension (i.e., stress) is often a prerequisite for stress corrosion, and in bent samples, the cracking almost always starts in the tension side. The corrosion rate is generally proportional to the load, such that the higher the load the shorter the life. In wrought products, the direction of the load in relation to the grain orientation is important. A load, applied in the short transverse direction, can be less than one-fifth of that for the long transverse or longitudinal direction.

[0006] The denuded zones near the grain boundary and sub boundaries can play an important role in crack generation. Crack initiation may be tied to the denuded zone around the grain boundary, which may remain super saturated the longest with the greatest electronegativity with respect to the matrix balance. The precipitates at the edge of the grain may advance the crack (like postage stamp perforations), but the electronegativity in the denuded region may be responsible for the crack initiation.

[0007] Stress corrosion susceptibility may be related to oxide film ductility and crack growth rate. This stress corrosion susceptibility can be a result of the crack growth passivation rate: if the crack grows faster than passivation occurs, failure ensues. Corrosion without stress tends to accelerate the eventual stress corrosion crack rate.

[0008] Structure can also be an important influence on stress corrosion cracking. Fine grain size decreases susceptibility, but a large number of sub-boundaries may produce a much larger improvement in resistance.

[0009] Stress corrosion cracking of aluminum alloys containing magnesium can involve a condition where magnesium-containing precipitates at the edge of a recrystallized grain in conditions where increased temperature and/or time promotes the nucleation and growth of certain magnesium-containing precipitates, such as the MgsAlx beta phase particles for a 5xxx aluminum alloy or the MgZm eta phase particles for a 7xxx aluminum alloy, at the recrystallized grain boundary to form a semi-continuous string, similar to a string of pearls. The relative electronegativity of the MgsAlx beta phase or the MgZm eta phase with respect to the surrounding material in the grain creates a corrosion event near the MgsAlx beta phase or the MgZm eta phase particles. Eventually, the corrosion cells, coupled with the MgsAlx beta phase or the MgZm eta phase, forms weak areas in the microstructure that crack or tear, similar to how perforations formed between postage stamps can be used to guide their separation.

[0010] Depending on the precipitates out of the matrix, the precipitate particles may or may not be continuous, or may be separated or scattered. However, the crack may nonetheless propagate and compromise the integrity and eventually cause the failure of the alloy structure.

SUMMARY

[0011] The term embodiment and like terms are intended to refer broadly to all of the subject matter of this disclosure and the claims below. Statements containing these terms should be understood not to limit the subject matter described herein or to limit the meaning or scope of the claims below. Embodiments of the present disclosure covered herein are defined by the claims below, not this summary. This summary is a high-level overview of various aspects of the disclosure and introduces some of the concepts that are further described in the Detailed Description section below. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used in isolation to determine the scope of the claimed subject matter. The subject matter should be understood by reference to appropriate portions of the entire specification of this disclosure, any or all drawings and each claim.

[0012] Described herein are stress corrosion cracking -resistant aluminum alloy products. The aluminum alloy products described herein advantageously exhibit good resistance to corrosion through the inclusion of calcium, strontium, and/or silver in the alloy, which allows the aluminum alloy products to resist crack formation and growth and fracture while under stress in corrosive environments. Stress corrosion cracking resistance and classification of metals, such as aluminum alloys, can be determined according to various standard test methods, such as ASTM G139-05(2015), Standard Test Method for Determining Stress- Corrosion Cracking Resistance of Heat-Treatable Aluminum Alloy Products Using Breaking Load Method, ASTM International, West Conshohocken, PA, 2015, or ASTM G64- 99(2013), Standard Classification of Resistance to Stress-Corrosion Cracking of Heat- Treatable Aluminum Alloys, ASTM International, West Conshohocken, PA, 2013, ASTM G47-98(2019), Standard Test Method for Determining Susceptibility to Stress-Corrosion Cracking of 2XXX and 7XXX Aluminum Alloy Products, ASTM International, West Conshohocken, PA, 2019, which are hereby incorporated by reference.

[0013] Advantageously, the inclusion of calcium, strontium, and/or silver in the alloy provides a level of corrosion resistance to magnesium containing aluminum alloys beyond that achievable by the inclusion of other alloying elements in the aluminum alloy. An example stress corrosion cracking-resistant aluminum alloy product comprises a plurality of alloying elements, including: 3 wt. % to 10 wt. % magnesium or 6 wt. % to 15 wt. % zinc, magnesium, and copper combined, and 0.001 wt. % to 0.1 wt. % calcium; and aluminum. In some embodiments, the stress corrosion cracking-resistant aluminum alloy product further comprises 0.001 wt. % to 0.1 wt. % strontium. In some embodiments, the stress corrosion cracking-resistant aluminum alloy product further comprises 0.001 wt. % to 0.1 wt. % silver. In embodiments, aluminum constitutes a remainder of the stress corrosion cracking-resistant aluminum alloy product (i.e., a remainder of the alloy beyond the alloying elements and any unavoidable impurities). The aluminum alloy may be in any suitable temper, such as an H temper or a T temper, which may be dependent upon the particular aluminum alloy used. Example aluminum alloys include 5xxx series aluminum alloys and 7xxx series aluminum alloys. Optionally, the plurality of alloying elements does not include zinc; that is, in some cases, the alloy does not contain zinc or only contains zinc in trace amounts or as unavoidable impurities. Optionally, the plurality of alloying elements further comprises zinc, such as in an amount of from 0.1 wt. % to 15 wt. %.

[0014] The stress corrosion cracking-resistant aluminum alloy products described herein can be prepared and processed according to any suitable methods. In embodiments, a stress corrosion cracking-resistant aluminum alloy product is prepared by casting an aluminum alloy comprising aluminum, 3 wt. % to 10 wt. % magnesium or 6 wt. % to 15 wt. % zinc, magnesium, and copper combined, and 0.001 wt. % to 0.01 wt. % calcium. Optionally, the cast aluminum product is subjected to one or more hot rolling processes and/or one or more cold rolling processes. Other example processes may include, but are not limited to, homogenization processes, heat treatment processes, aging processes, or the like.

[0015] In embodiments, magnesium containing aluminum alloys may contain magnesium-containing precipitates, which may correspond to intermetallic particles.

Example magnesium-containing precipitates include, MgsAlx beta phase particles and MgZm eta phase particles. The presence of the different magnesium-containing precipitates may depend upon the particular alloy and processing conditions. Magnesium-containing precipitates may, in some cases, serve as corrosion initiation sites and allow for corrosion to propagate and for stress corrosion cracking to be problematic. By including calcium in the aluminum alloys, the presence or concentrations of magnesium-containing precipitates may be limited or reduced and/or the corrosion potential of the magnesium-containing precipitates may be reduced. In some embodiments, a stress corrosion cracking-resistant aluminum alloy product comprises less than 0.05 wt. % of magnesium-containing precipitates, such as Mg5Al8 beta phase particles or MgZm eta phase particles. In some cases, magnesium- containing precipitates may also comprise Zn. [0016] As noted above, the presence of magnesium-containing precipitates may be dictated by the specific composition of an aluminum alloy as well as the processing conditions by which the aluminum alloy is made. In some embodiments, magnesium- containing precipitates in a stress corrosion cracking -resistant aluminum alloy product may be formed through exposure to a temperature of from 50 °C to 600 °C. Optionally, the magnesium-containing precipitates are formed during aging of an aluminum alloy product. [0017] By including calcium, strontium, and/or silver in the alloy, calcium, strontium, and/or silver may be present in magnesium-containing precipitates and/or may modify the composition of the magnesium-containing precipitates as compared to alloys where calcium, strontium, and/or silver may only be present in trace amounts. Inclusion of calcium, strontium, and/or silver in a magnesium-containing precipitate may lower the corrosion potential of the magnesium-containing precipitate as compared to magnesium-containing precipitates that do not include calcium, strontium, and/or silver. Optionally, a presence of the calcium, strontium, and/or silver in the aluminum alloy product reduces an amount of the magnesium-containing precipitates in the stress corrosion cracking-resistant aluminum alloy product as referenced to a comparable aluminum alloy product comprising 3 wt. % to 10 wt. % magnesium or 6 wt. % to 15 wt. % zinc, magnesium, and copper combined, and less than 0.001 wt. % calcium, strontium, and/or silver and subjected to identical processing conditions.

[0018] When calcium, strontium, and/or silver are present in an aluminum alloy, precipitates containing calcium, strontium, and/or silver may develop at grain boundaries. Optionally, a stress corrosion cracking -resistant aluminum alloy product may comprise one or more phases containing calcium, strontium, and/or silver at grain boundaries of the aluminum alloy product. In some cases, the one or more phases containing calcium, strontium, and/or silver may be produced by exposure to an elevated temperature of from 50 °C to 600 °C and/or by aging. Optionally, the one or more phases containing calcium, strontium, and/or silver comprises calcium metal, strontium metal, and/or silver metal. Optionally, one phase of the one or more phases containing calcium, strontium, and/or silver comprises calcium and magnesium. Optionally, one phase of the one or more phases containing calcium, strontium, and/or silver comprises strontium and magnesium. Optionally, one phase of the one or more phases containing calcium, strontium, and/or silver comprises silver and magnesium. Optionally, one phase of the one or more phases containing calcium, strontium, and/or silver comprises calcium and aluminum. Optionally, one phase of the one or more phases containing calcium, strontium, and/or silver comprises strontium and aluminum. Optionally, one phase of the one or more phases containing calcium, strontium, and/or silver comprises silver and aluminum. Optionally, one phase of the one or more phases containing calcium, strontium, and/or silver comprises calcium, aluminum, and magnesium. Optionally, one phase of the one or more phases containing calcium, strontium, and/or silver comprises strontium, aluminum, and magnesium. Optionally, one phase of the one or more phases containing calcium, strontium, and/or silver comprises calcium, strontium, aluminum, and magnesium. Optionally, one phase of the one or more phases containing calcium, strontium, and/or silver comprises calcium, silver, aluminum, and magnesium. Optionally, one phase of the one or more phases containing calcium, strontium, and/or silver comprises strontium, silver, aluminum, and magnesium. Optionally, one phase of the one or more phases containing calcium, strontium, and/or silver comprises calcium, strontium, silver, aluminum, and magnesium. In some cases, the one or more phases containing calcium, strontium, and/or silver may at least partially surround magnesium-containing precipitates located at the grain boundaries, which may optionally limit or reduce the corrosion potential of the magnesium- containing precipitates.

[0019] In another aspect, methods of making stress corrosion cracking-resistant aluminum alloy products are described. An example method of this aspect comprises providing an aluminum alloy in a molten state as a molten aluminum alloy, such as an aluminum alloy that comprises aluminum, 3 wt. % to 10 wt. % magnesium or 6 wt. % to 15 wt. % zinc, magnesium, and copper combined, and 0.001 wt. % to 0.1 wt. % calcium; and casting the molten aluminum alloy to form an aluminum alloy product. Other processing techniques may also be employed in the methods of this aspect. For example, methods of this aspect may optionally comprise one or more of homogenizing the aluminum alloy product to form a homogenized aluminum alloy product; aging the aluminum alloy product; cold rolling the aluminum alloy product; hot rolling the aluminum alloy product; subjecting the aluminum alloy product to an elevated temperature; or subjecting the aluminum alloy product to a corrosive environment. Advantageously, the stress corrosion cracking-resistant aluminum alloys described herein may be useful in marine environments or other high corrosion or corrosion susceptible environments.

[0020] Advantageously a presence of calcium, strontium, and/or silver in the aluminum alloy product may increase an amount of time needed to induce stress corrosion cracks in the aluminum alloy product as referenced to a comparable aluminum alloy product comprising 3 wt. % to 10 wt. % magnesium or 6 wt. % to 15 wt. % zinc, magnesium, and copper combined, and less than 0.001 wt. % calcium, strontium, and/or silver. [0021] Other objects and advantages will be apparent from the following detailed description of non-limiting examples.

BRIEF DESCRIPTION OF THE FIGURES

[0022] The specification makes reference to the following appended figures, in which use of like reference numerals in different figures is intended to illustrate like or analogous components.

[0023] FIG. 1 A schematically illustrates the formation of magnesium-containing precipitates at grain boundaries.

[0024] FIG. IB schematically illustrates corrosion occurring near magnesium-containing precipitates particles at grain boundaries.

[0025] FIG. 2 provides an overview of an exemplary method of making an aluminum alloy product.

DETAILED DESCRIPTION

[0026] Described herein are aluminum alloy products and systems and methods of making and using aluminum alloy products. The aluminum alloy products described herein include those comprising magnesium-strengthened aluminum alloys with added calcium, strontium, and/or silver. Advantageously, the added calcium, strontium, and/or silver reduce the aluminum alloy’s susceptibility to stress corrosion cracking. By adding calcium, strontium, and/or silver, the growth of magnesium-containing precipitates, such as MgsAlx beta phase particles or MgZm eta phase particles at the grain boundaries may optionally be altered and/or reduced as compared to aluminum alloys containing no or only trace amounts of calcium, strontium, and/or silver. The altered and/or reduced growth of beta or eta phase particles can reduce or limit corrosion that may occur between the beta phase and the surrounding grains, thereby suppressing stress corrosion cracking.

Definitions and Descriptions:

[0027] As used herein, the terms “invention,” “the invention,” “this invention” and “the present invention” are intended to refer broadly to all of the subject matter of this patent application and the claims below. Statements containing these terms should be understood not to limit the subject matter described herein or to limit the meaning or scope of the patent claims below. [0028] In this description, reference is made to alloys identified by AA numbers and other related designations, such as “series” or “7xxx.” For an understanding of the number designation system most commonly used in naming and identifying aluminum and its alloys, see “International Alloy Designations and Chemical Composition Limits for Wrought Aluminum and Wrought Aluminum Alloys” or “Registration Record of Aluminum Association Alloy Designations and Chemical Compositions Limits for Aluminum Alloys in the Form of Castings and Ingot,” both published by The Aluminum Association.

[0029] As used herein, a plate generally has a thickness of greater than about 15 mm. For example, a plate may refer to an aluminum product having a thickness of greater than about 15 mm, greater than about 20 mm, greater than about 25 mm, greater than about 30 mm, greater than about 35 mm, greater than about 40 mm, greater than about 45 mm, greater than about 50 mm, or greater than about 100 mm.

[0030] As used herein, a shate (also referred to as a sheet plate) generally has a thickness of from about 4 mm to about 15 mm. For example, a shate may have a thickness of about 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, about 11 mm, about 12 mm, about 13 mm, about 14 mm, or about 15 mm.

[0031] As used herein, a sheet generally refers to an aluminum product having a thickness of less than about 4 mm. For example, a sheet may have a thickness of less than about 4 mm, less than about 3 mm, less than about 2 mm, less than about 1 mm, less than about 0.5 mm, or less than about 0.3 mm (e.g., about 0.2 mm).

[0032] Reference may be made in this application to alloy temper or condition. For an understanding of the alloy temper descriptions most commonly used, see “American National Standards (ANSI) H35 on Alloy and Temper Designation Systems.” An F condition or temper refers to an aluminum alloy as fabricated. An O condition or temper refers to an aluminum alloy after annealing. An Hxx condition or temper, also referred to herein as an H temper, refers to a non-heat treatable aluminum alloy after cold rolling with or without thermal treatment (e.g., annealing). Suitable H tempers include HX1, HX2, HX3 HX4, HX5, HX6, HX7, HX8, or HX9 tempers. A T1 condition or temper refers to an aluminum alloy cooled from hot working and naturally aged (e.g., at room temperature). A T2 condition or temper refers to an aluminum alloy cooled from hot working, cold worked and naturally aged. A T3 condition or temper refers to an aluminum alloy solution heat treated, cold worked, and naturally aged. A T4 condition or temper refers to an aluminum alloy solution heat treated and naturally aged. A T5 condition or temper refers to an aluminum alloy cooled from hot working and artificially aged (at elevated temperatures). A T6 condition or temper refers to an aluminum alloy solution heat treated and artificially aged. A T7 condition or temper refers to an aluminum alloy solution heat treated and artificially overaged. A T8x condition or temper refers to an aluminum alloy solution heat treated, cold worked, and artificially aged. A T9 condition or temper refers to an aluminum alloy solution heat treated, artificially aged, and cold worked. A W condition or temper refers to an aluminum alloy after solution heat treatment.

[0033] As used herein, terms such as “cast metal product,” “cast product,” “cast aluminum alloy product,” and the like are interchangeable and refer to a product produced by direct chill casting (including direct chill co-casting) or semi-continuous casting, continuous casting (including, for example, by use of a twin belt caster, a twin roll caster, a block caster, or any other continuous caster), electromagnetic casting, hot top casting, or any other casting method.

[0034] As used herein, the meaning of “room temperature” can include a temperature of from about 15 °C to about 30 °C, for example about 15 °C, about 16 °C, about 17 °C, about 18 °C, about 19 °C, about 20 °C, about 21 °C, about 22 °C, about 23 °C, about 24 °C, about 25 °C, about 26 °C, about 27 °C, about 28 °C, about 29 °C, or about 30 °C. As used herein, the meaning of “ambient conditions” can include temperatures of about room temperature, relative humidity of from about 20 % to about 100 %, and barometric pressure of from about 975 millibar (mbar) to about 1050 mbar. For example, relative humidity can be about 20 %, about 21 %, about 22 %, about 23 %, about 24 %, about 25 %, about 26 %, about 27 %, about 28 %, about 29 %, about 30 %, about 31 %, about 32 %, about 33 %, about 34 %, about 35 %, about 36 %, about 37 %, about 38 %, about 39 %, about 40 %, about 41 %, about 42 %, about 43 %, about 44 %, about 45 %, about 46 %, about 47 %, about 48 %, about 49 %, about 50 %, about 51 %, about 52 %, about 53 %, about 54 %, about 55 %, about 56 %, about 57 %, about 58 %, about 59 %, about 60 %, about 61 %, about 62 %, about 63 %, about 64 %, about 65 %, about 66 %, about 67 %, about 68 %, about 69 %, about 70 %, about 71 %, about 72 %, about 73 %, about 74 %, about 75 %, about 76 %, about 77 %, about 78 %, about 79 %, about 80 %, about 81 %, about 82%, about 83 %, about 84 %, about 85 %, about 86 %, about 87 %, about 88 %, about 89 %, about 90 %, about 91 %, about 92 %, about 93 %, about 94 %, about 95 %, about 96 %, about 97 %, about 98 %, about 99 %, about 100 %, or anywhere in between. For example, barometric pressure can be about 975 mbar, about 980 mbar, about 985 mbar, about 990 mbar, about 995 mbar, about 1000 mbar, about 1005 mbar, about 1010 mbar, about 1015 mbar, about 1020 mbar, about 1025 mbar, about 1030 mbar, about 1035 mbar, about 1040 mbar, about 1045 mbar, about 1050 mbar, or anywhere in between.

[0035] All ranges disclosed herein are to be understood to encompass any and all subranges subsumed therein. For example, a stated range of “1 to 10” should be considered to include any and all subranges between (and inclusive of) the minimum value of 1 and the maximum value of 10; that is, all subranges beginning with a minimum value of 1 or more, e.g. 1 to 6.1, and ending with a maximum value of 10 or less, e.g., 5.5 to 10. Unless stated otherwise, the expression “up to” when referring to the compositional amount of an element means that element is optional and includes a zero percent composition of that particular element. Unless stated otherwise, all compositional percentages are in weight percent (wt. %).

[0036] As used herein, the meaning of “a,” “an,” and “the” includes singular and plural references unless the context clearly dictates otherwise.

[0037] In the following examples, the aluminum alloy products and their components are described in terms of their elemental composition in weight percent (wt. %). In each alloy, the remainder is aluminum, with a maximum wt. % of 0.15 % for the sum of all impurities. [0038] Incidental elements, such as grain refiners and deoxidizers, or other additives may be present in aspects of the invention and may add other characteristics on their own without departing from or significantly altering the alloy described herein or the characteristics of the alloy described herein.

[0039] Unavoidable impurities, including materials or elements, may be present in the alloy in minor amounts due to inherent properties of aluminum or leaching from contact with processing equipment. Some impurities found in aluminum may include iron and silicon.

The alloy, as described, may contain no more than about 0.25 wt. % of any element besides the alloying elements, incidental elements, and unavoidable impurities.

[0040] Described herein are methods of treating and preparing metals and metal alloys, including aluminum, aluminum alloys, magnesium, magnesium alloys, magnesium composites, and steel, among others, and the resultant treated and prepared metals and metal alloys. In some examples, the metals for use in the methods described herein include aluminum alloys, for example, 5xxx series aluminum alloys or 7xxx series aluminum alloys. In some examples, the materials for use in the methods described herein include non-ferrous materials, including aluminum, aluminum alloys, magnesium, magnesium-based materials, magnesium alloys, magnesium composites, titanium, titanium-based materials, titanium alloys, copper, copper-based materials, composites, sheets used in composites, or any other suitable metal, non-metal or combination of materials. Monolithic as well as non-monolithic, such as roll-bonded materials, cladded alloys, cladding layers, composite materials, such as but not limited to carbon fiber-containing materials, or various other materials are also useful with the methods described herein. In some examples, aluminum alloys containing iron are useful with the methods described herein.

[0041] Non-limiting exemplary 5xxx series aluminum alloys for use as the aluminum alloy product can include AA5005, AA5005A, AA5205, AA5305, AA5505, AA5605, AA5006, AA5106, AA5010, AA5110, AA5110A, AA5210, AA5310, AA5016, AA5017, AA5018, AA5018A, AA5019, AA5019A, AA5119, AA5119A, AA5021, AA5022, AA5023, AA5024, AA5026, AA5027, AA5028, AA5040, AA5140, AA5041, AA5042, AA5043, AA5049, AA5149, AA5249, AA5349, AA5449, AA5449A, AA5050, AA5050A, AA5050C, AA5150, AA5051, AA5051A, AA5151, AA5251, AA5251A, AA5351, AA5451, AA5052, AA5252, AA5352, AA5154, AA5154A, AA5154B, AA5154C, AA5254, AA5354, AA5454, AA5554, AA5654, AA5654A, AA5754, AA5854, AA5954, AA5056, AA5356, AA5356A, AA5456, AA5456A, AA5456B, AA5556, AA5556A, AA5556B, AA5556C, AA5257, AA5457, AA5557, AA5657, AA5058, AA5059, AA5070, AA5180, AA5180A, AA5082, AA5182, AA5083, AA5183, AA5183A, AA5283, AA5283A, AA5283B, AA5383, AA5483, AA5086, AA5186, AA5087, AA5187, or AA5088.

[0042] Non-limiting exemplary 7xxx series aluminum alloys for use in the methods described herein can include AA7011, AA7019, AA7020, AA7021, AA7039, AA7072, AA7075, AA7085, AA7108, AA7108A, AA7015, AA7017, AA7018, AA7019A, AA7024, AA7025, AA7028, AA7030, AA7031, AA7033, AA7035, AA7035A, AA7046, AA7046A, AA7003, AA7004, AA7005, AA7009, AA7010, AA7011, AA7012, AA7014, AA7016, AA7116, AA7122, AA7023, AA7026, AA7029, AA7129, AA7229, AA7032, AA7033, AA7034, AA7036, AA7136, AA7037, AA7040, AA7140, AA7041, AA7049, AA7049A, AA7149,7204, AA7249, AA7349, AA7449, AA7050, AA7050A, AA7150, AA7250, AA7055, AA7155, AA7255, AA7056, AA7060, AA7064, AA7065, AA7068, AA7168, AA7175, AA7475, AA7076, AA7178, AA7278, AA7278A, AA7081, AA7181, AA7185, AA7090, AA7093, AA7095, or AA7099.

[0043] The following description will serve to further illustrate the present invention without, at the same time, however, constituting any limitation thereof. On the contrary, it is to be clearly understood that resort may be had to various embodiments, modifications, and equivalents thereof which, after reading the description herein, may suggest themselves to those skilled in the art without departing from the spirit of the invention. [0044] High-strength and durable aluminum alloys are desirable for use in a number of different applications. Magnesium in solid solution is effective in strengthening the aluminum alloys, and the alloys are also relatively inert because magnesium oxide that forms at the surface creates a barrier to corrosion. However, aluminum alloys having a magnesium, such as a relatively high content magnesium in the case of certain 5xxx aluminum alloys or a relatively high combined content of zinc, magnesium, and copper in the case of certain 7xxx aluminum alloys, may, nonetheless, experience stress corrosion cracking.

[0045] Stress corrosion cracking of aluminum alloys containing magnesium involves a condition where magnesium-containing particles precipitate at the edge of a recrystallized grain at increased temperature and/or over time, which promotes the nucleation and growth of MgsAls beta phase particles or MgZm eta phase particles at the recrystallized grain boundary. FIG. 1 A schematically illustrates a grain structure of a magnesium-containing aluminum alloy and shows the presence of the MgsAls beta phase particles 105 at the grain boundaries 110. The relative electronegativity of the MgsAls beta phase with respect to the surrounding material in the grain may generate a corrosion event near the MgsAls beta phase particles. Eventually, the corrosion cells, coupled with the MgsAls beta phase, may form weak areas 115 in the microstructure, as schematically illustrated in the grain structure depicted in FIG. IB, which may crack or tear under stress. Similar corrosion behavior may be observed in aluminum alloys with discontinuous precipitation of MgZm eta phase along grain boundaries. Although MgsAls and MgZm are described as exemplary magnesium-containing precipitates or magnesium-containing intermetallic compounds that may form particles at the grain boundaries, other magnesium-containing phases or compounds, such as MgsAb or others, may also be formed at the grain boundaries of the magnesium-strengthened aluminum alloy and/or may make the alloy susceptible to stress corrosion cracking.

[0046] In the case of 5xxx aluminum alloys, precipitation of magnesium at grain boundaries, such as formation of MgsAls beta phase particles at grain boundaries, may be more prominent when the magnesium content is 3 wt. % or higher, and the MgsAls beta phase may optionally form a semi-continuous string of particles along some grain boundaries. However, depending on the processing and/or operating conditions, magnesium precipitation, such as MgsAls beta phase formation, may also occur when the magnesium content is below 3 wt. %. Depending on the magnesium content, the magnesium-containing precipitates may or may not be continuous, or may be separated or scattered. However, cracks may nonetheless propagate and compromise strength, and may eventually cause failure of the alloy product. [0047] In the case of 7xxx aluminum alloys, precipitation of magnesium at grain boundaries, such as formation of MgZm eta phase particles at grain boundaries, may be more prominent when a combined content of magnesium zinc, magnesium, and copper is 6 wt. % or higher, and the MgZm eta phase may optionally form a semi-continuous string of particles along some grain boundaries. However, depending on the processing and/or operating conditions, magnesium precipitation, such as MgZm eta phase formation, may also occur when the combined content of zinc, magnesium, and copper is below 6 wt. %. Depending on the magnesium content, the magnesium-containing precipitates may or may not be continuous, or may be separated or scattered. However, cracks may nonetheless propagate and compromise strength, and may eventually cause failure of the alloy product.

[0048] Increased or elevated temperatures may lead to the growth of the magnesium- containing precipitates, such as temperatures from 50 °C to 600 °C. In some embodiments, the elevated temperature that may lead to the growth of the magnesium-containing precipitates, such as MgsAls or MgZm may not be very high, and may be below 200 °C, such as below 150 °C, below 100 °C, below 50 °C, or even lower. Therefore, heat treatment, if performed for magnesium-strengthened aluminum alloys, may be limited or require close control so as to limit the formation of the magnesium-containing precipitates. However, increases in temperature may not be avoided and/or may occur during subsequent handling of products made of various magnesium-strengthened aluminum alloys, such as during welding, paint baking, etc. Therefore, the magnesium-containing precipitates may inevitably form and create preferential corrosion sites which may eventually lead to stress corrosion cracking. [0049] To suppress stress corrosion cracking, calcium, strontium and/or silver may be added to magnesium-strengthened aluminum alloys to reduce corrosion that may otherwise occur at the grain boundaries due to the presence of the magnesium-containing precipitates when no calcium, strontium, and/or silver are added. By adding calcium, strontium, and/or silver, the growth of the magnesium-containing precipitates may be altered. Without intending to be bound to any particular theory, the inventors believe that, given a relatively low solubility in aluminum, calcium or strontium, or optionally silver, may precipitate, along with magnesium, at the grain boundaries when the magnesium-strengthened aluminum alloy is subjected to an elevated temperature. The magnesium precipitate, the calcium precipitate, the strontium precipitate, and/or the silver precipitate may form one or more intermetallic compounds that may or may not include aluminum. The formation of intermetallic compounds containing magnesium, calcium, strontium, and/or silver may reduce the amount of magnesium that may otherwise form magnesium-containing precipitates, such as MgsAlx and/or MgZm. The overall reduction in the magnesium-containing precipitates may lead to reduced corrosion at the grain boundaries, thereby suppressing or reducing the stress corrosion cracking phenomenon, such as when compared to magnesium-containing aluminum alloys that lack or only contain trace amounts of calcium, strontium, and/or silver. A trace amount of each of calcium, strontium, and/or silver may refer to an amount of each of calcium, strontium, and/or silver that may be less than 0.001 wt. %. Alternatively, the precipitates or particles containing calcium, strontium, and/or silver may coat and/or be positioned adjacent to the magnesium-containing precipitates that may be formed at the grain boundaries, thereby limiting the corrosion reaction between the magnesium-containing precipitates and the surrounding grains. The ductility of the oxide film at the crack tip may also be modified constructively by adding calcium and/or strontium. Additionally, calcium and/or strontium can vary or positively form a very stable pacifying layer in the region of the crack tip, reducing the overall growth rate of an initiated crack in a denuded region of the grain. Further, the calcium, strontium, and/or silver remaining in the grains may alter the electronegativity of the grains themselves and/or a relative electronegativity of the grains as compared to the magnesium-containing precipitates, and thus limit the corrosion that may occur where the magnesium-containing precipitates may be present.

[0050] Depending on the application, the amount of calcium that may be added to the magnesium-strengthened aluminum alloy may range from 0.001% to 0.1% by weight. In some embodiments, the weight percent of calcium in the alloy may be from 0.001% to 0.1%, from 0.005% to 0.1%, from 0.01% to 0.1%, from 0.015% to 0.1%, from 0.02% to 0.1%, from 0.025% to 0.1%, from 0.03% to 0.1%, from 0.035% to 0.1%, from 0.04% to 0.1%, from

0.045% to 0.1%, from 0.05% to 0.1%, from 0.055% to 0.1%, from 0.06% to 0.1%, from

0.065% to 0.1%, from 0.07% to 0.1%, from 0.075% to 0.1%, from 0.08% to 0.1%, from

0.085% to 0.1%, from 0.09% to 0.1%, from 0.095% to 0.1%, from 0.001% to 0.095%, from

0.005% to 0.095%, from 0.01% to 0.095%, from 0.015% to 0.095%, from 0.02% to 0.095%, from 0.025% to 0.095%, from 0.03% to 0.095%, from 0.035% to 0.095%, from 0.04% to 0.095%, from 0.045% to 0.095%, from 0.05% to 0.095%, from 0.055% to 0.095%, from 0.06% to 0.095%, from 0.065% to 0.095%, from 0.07% to 0.095%, from 0.075% to 0.095%, from 0.08% to 0.095%, from 0.085% to 0.095%, from 0.09% to 0.095%, from 0.001% to 0.09%, from 0.005% to 0.09%, from 0.01% to 0.09%, from 0.015% to 0.09%, from 0.02% to

0.09%, from 0.025% to 0.09%, from 0.03% to 0.09%, from 0.035% to 0.09%, from 0.04% to

0.09%, from 0.045% to 0.09%, from 0.05% to 0.09%, from 0.055% to 0.09%, from 0.06% to

0.09%, from 0.065% to 0.09%, from 0.07% to 0.09%, from 0.075% to 0.09%, from 0.08% to 0.09%, from 0.085% to 0.09%, from 0.001% to 0.085%, from 0.005% to 0.085%, from 0.01% to 0.085%, from 0.015% to 0.085%, from 0.02% to 0.085%, from 0.025% to 0.085%, from 0.03% to 0.085%, from 0.035% to 0.085%, from 0.04% to 0.085%, from 0.045% to 0.085%, from 0.05% to 0.085%, from 0.055% to 0.085%, from 0.06% to 0.085%, from 0.065% to 0.085%, from 0.07% to 0.085%, from 0.075% to 0.085%, from 0.08% to 0.085%, from 0.001% to 0.08%, from 0.005% to 0.08%, from 0.01% to 0.08%, from 0.015% to 0.08%, from 0.02% to 0.08%, from 0.025% to 0.08%, from 0.03% to 0.08%, from 0.035% to 0.08%, from 0.04% to 0.08%, from 0.045% to 0.08%, from 0.05% to 0.08%, from 0.055% to 0.08%, from 0.06% to 0.08%, from 0.065% to 0.08%, from 0.07% to 0.08%, from 0.075% to 0.08%, from 0.001% to 0.075%, from 0.005% to 0.075%, from 0.01% to 0.075%, from 0.015% to 0.075%, from 0.02% to 0.075%, from 0.025% to 0.075%, from 0.03% to 0.075%, from 0.035% to 0.075%, from 0.04% to 0.075%, from 0.045% to 0.075%, from 0.05% to 0.075%, from 0.055% to 0.075%, from 0.06% to 0.075%, from 0.065% to 0.075%, from 0.07% to 0.075%, from 0.001% to 0.07%, from 0.005% to 0.07%, from 0.01% to 0.07%, from 0.015% to 0.07%, from 0.02% to 0.07%, from 0.025% to 0.07%, from 0.03% to 0.07%, from 0.035% to 0.07%, from 0.04% to 0.07%, from 0.045% to 0.07%, from 0.05% to 0.07%, from 0.055% to 0.07%, from 0.06% to 0.07%, from 0.065% to 0.07, from 0.001% to 0.065%, from 0.005% to 0.065%, from 0.01% to 0.065%, from 0.015% to 0.065%, from 0.02% to 0.065%, from 0.025% to 0.065%, from 0.03% to 0.065%, from 0.035% to 0.065%, from 0.04% to 0.065%, from 0.045% to 0.065%, from 0.05% to 0.065%, from 0.055% to 0.065%, from 0.06% to 0.065%, from 0.001% to 0.06%, from 0.005% to 0.06%, from 0.01% to 0.06%, from 0.015% to 0.06%, from 0.02% to 0.06%, from 0.025% to 0.06%, from 0.03% to 0.06%, from 0.035% to 0.06%, from 0.04% to 0.06%, from 0.045% to 0.06%, from 0.05% to 0.06%, from 0.055% to 0.06%, from 0.001% to 0.055%, from 0.005% to 0.055%, from 0.01% to 0.055%, from 0.015% to 0.055%, from 0.02% to 0.055%, from 0.025% to 0.055%, from 0.03% to 0.055%, from 0.035% to 0.055%, from 0.04% to 0.055%, from 0.045% to 0.055%, from 0.05% to 0.055%, from 0.001% to 0.05%, from 0.005% to 0.05%, from 0.01% to 0.05%, from 0.015% to 0.05%, from 0.02% to 0.05%, from 0.025% to 0.05%, from 0.03% to 0.05%, from 0.035% to 0.05%, from 0.04% to 0.05%, from 0.045% to 0.05%, from 0.001% to 0.045%, from 0.005% to 0.045%, from 0.01% to 0.045%, from 0.015% to 0.045%, from 0.02% to 0.045%, from 0.025% to 0.045%, from 0.03% to 0.045%, from 0.035% to 0.045%, from 0.04% to 0.045%, from 0.001% to 0.04%, from 0.005% to 0.04%, from 0.01% to 0.04%, from 0.015% to 0.04%, from 0.02% to 0.04%, from 0.025% to 0.04%, from 0.03% to 0.04%, from 0.035% to 0.04%, from 0.001% to 0.035%, from 0.005% to 0.035%, from 0.01% to 0.035%, from 0.015% to 0.035%, from 0.02% to 0.035%, from 0.025% to 0.035%, from 0.03% to 0.035%, from 0.001% to 0.03%, from 0.005% to 0.03%, from 0.01% to 0.03%, from 0.015% to 0.03%, from 0.02% to 0.03%, from 0.025% to 0.03%, from 0.001% to 0.025%, from 0.005% to 0.025%, from 0.01% to 0.025%, from 0.015% to 0.025%, from 0.02% to 0.025%, from 0.001% to 0.02%, from 0.005% to 0.02%, from 0.01% to 0.02%, from 0.015% to 0.02%, from 0.001% to 0.015%, from 0.005% to 0.015%, from 0.01% to 0.015%, from 0.001% to 0.01%, from 0.005% to 0.01%, or from 0.001% to 0.005%.

[0051] Depending on the application, the amount of strontium that may be added to the magnesium-strengthened aluminum alloy may range from 0.001% to 0.1% by weight. In some embodiments, the weight percent of strontium in the alloy may be from 0.001% to 0.1%, from 0.005% to 0.1%, from 0.01% to 0.1%, from 0.015% to 0.1%, from 0.02% to 0.1%, from 0.025% to 0.1%, from 0.03% to 0.1%, from 0.035% to 0.1%, from 0.04% to 0.1%, from 0.045% to 0.1%, from 0.05% to 0.1%, from 0.055% to 0.1%, from 0.06% to 0.1%, from 0.065% to 0.1%, from 0.07% to 0.1%, from 0.075% to 0.1%, from 0.08% to 0.1%, from 0.085% to 0.1%, from 0.09% to 0.1%, from 0.095% to 0.1%, from 0.001% to 0.095%, from 0.005% to 0.095%, from 0.01% to 0.095%, from 0.015% to 0.095%, from 0.02% to 0.095%, from 0.025% to 0.095%, from 0.03% to 0.095%, from 0.035% to 0.095%, from 0.04% to 0.095%, from 0.045% to 0.095%, from 0.05% to 0.095%, from 0.055% to 0.095%, from 0.06% to 0.095%, from 0.065% to 0.095%, from 0.07% to 0.095%, from 0.075% to 0.095%, from 0.08% to 0.095%, from 0.085% to 0.095%, from 0.09% to 0.095%, from 0.001% to 0.09%, from 0.005% to 0.09%, from 0.01% to 0.09%, from 0.015% to 0.09%, from 0.02% to 0.09%, from 0.025% to 0.09%, from 0.03% to 0.09%, from 0.035% to 0.09%, from 0.04% to 0.09%, from 0.045% to 0.09%, from 0.05% to 0.09%, from 0.055% to 0.09%, from 0.06% to 0.09%, from 0.065% to 0.09%, from 0.07% to 0.09%, from 0.075% to 0.09%, from 0.08% to 0.09%, from 0.085% to 0.09%, from 0.001% to 0.085%, from 0.005% to 0.085%, from 0.01% to 0.085%, from 0.015% to 0.085%, from 0.02% to 0.085%, from 0.025% to 0.085%, from 0.03% to 0.085%, from 0.035% to 0.085%, from 0.04% to 0.085%, from 0.045% to 0.085%, from 0.05% to 0.085%, from 0.055% to 0.085%, from 0.06% to 0.085%, from 0.065% to 0.085%, from 0.07% to 0.085%, from 0.075% to 0.085%, from 0.08% to 0.085%, from 0.001% to 0.08%, from 0.005% to 0.08%, from 0.01% to 0.08%, from 0.015% to 0.08%, from 0.02% to 0.08%, from 0.025% to 0.08%, from 0.03% to 0.08%, from 0.035% to 0.08%, from 0.04% to 0.08%, from 0.045% to 0.08%, from 0.05% to 0.08%, from 0.055% to 0.08%, from 0.06% to 0.08%, from 0.065% to 0.08%, from 0.07% to 0.08%, from 0.075% to 0.08%, from 0.001% to 0.075%, from 0.005% to 0.075%, from 0.01% to 0.075%, from 0.015% to 0.075%, from 0.02% to 0.075%, from 0.025% to 0.075%, from 0.03% to 0.075%, from 0.035% to 0.075%, from 0.04% to 0.075%, from 0.045% to 0.075%, from 0.05% to 0.075%, from 0.055% to 0.075%, from 0.06% to 0.075%, from 0.065% to 0.075%, from 0.07% to 0.075%, from 0.001% to 0.07%, from 0.005% to 0.07%, from 0.01% to 0.07%, from 0.015% to 0.07%, from 0.02% to 0.07%, from 0.025% to 0.07%, from 0.03% to 0.07%, from 0.035% to 0.07%, from 0.04% to 0.07%, from 0.045% to 0.07%, from 0.05% to 0.07%, from 0.055% to 0.07%, from 0.06% to 0.07%, from 0.065% to 0.07, from 0.001% to 0.065%, from 0.005% to 0.065%, from 0.01% to 0.065%, from 0.015% to 0.065%, from 0.02% to 0.065%, from 0.025% to 0.065%, from 0.03% to 0.065%, from 0.035% to 0.065%, from 0.04% to 0.065%, from 0.045% to 0.065%, from 0.05% to 0.065%, from 0.055% to 0.065%, from 0.06% to 0.065%, from 0.001% to 0.06%, from 0.005% to 0.06%, from 0.01% to 0.06%, from 0.015% to 0.06%, from 0.02% to 0.06%, from 0.025% to 0.06%, from 0.03% to 0.06%, from 0.035% to 0.06%, from 0.04% to 0.06%, from 0.045% to 0.06%, from 0.05% to 0.06%, from 0.055% to 0.06%, from 0.001% to 0.055%, from 0.005% to 0.055%, from 0.01% to 0.055%, from 0.015% to 0.055%, from 0.02% to 0.055%, from 0.025% to 0.055%, from 0.03% to 0.055%, from 0.035% to 0.055%, from 0.04% to 0.055%, from 0.045% to 0.055%, from 0.05% to 0.055%, from 0.001% to 0.05%, from 0.005% to 0.05%, from 0.01% to 0.05%, from 0.015% to 0.05%, from 0.02% to 0.05%, from 0.025% to 0.05%, from 0.03% to 0.05%, from 0.035% to 0.05%, from 0.04% to 0.05%, from 0.045% to 0.05%, from

0.001% to 0.045%, from 0.005% to 0.045%, from 0.01% to 0.045%, from 0.015% to 0.045%, from 0.02% to 0.045%, from 0.025% to 0.045%, from 0.03% to 0.045%, from 0.035% to 0.045%, from 0.04% to 0.045%, from 0.001% to 0.04%, from 0.005% to 0.04%, from 0.01% to 0.04%, from 0.015% to 0.04%, from 0.02% to 0.04%, from 0.025% to 0.04%, from 0.03% to 0.04%, from 0.035% to 0.04%, from 0.001% to 0.035%, from 0.005% to 0.035%, from 0.01% to 0.035%, from 0.015% to 0.035%, from 0.02% to 0.035%, from 0.025% to 0.035%, from 0.03% to 0.035%, from 0.001% to 0.03%, from 0.005% to 0.03%, from 0.01% to 0.03%, from 0.015% to 0.03%, from 0.02% to 0.03%, from 0.025% to 0.03%, from 0.001% to 0.025%, from 0.005% to 0.025%, from 0.01% to 0.025%, from 0.015% to 0.025%, from 0.02% to 0.025%, from 0.001% to 0.02%, from 0.005% to 0.02%, from 0.01% to 0.02%, from 0.015% to 0.02%, from 0.001% to 0.015%, from 0.005% to 0.015%, from 0.01% to 0.015%, from 0.001% to 0.01%, from 0.005% to 0.01%, or from 0.001% to 0.005%.

[0052] Depending on the application, the amount of silver that may be added to the magnesium-strengthened aluminum alloy may range from 0.001% to 0.1% by weight. In some embodiments, the weight percent of silver in the alloy may be from 0.001% to 0.1%, from 0.005% to 0.1%, from 0.01% to 0.1%, from 0.015% to 0.1%, from 0.02% to 0.1%, from 0.025% to 0.1%, from 0.03% to 0.1%, from 0.035% to 0.1%, from 0.04% to 0.1%, from 0.045% to 0.1%, from 0.05% to 0.1%, from 0.055% to 0.1%, from 0.06% to 0.1%, from 0.065% to 0.1%, from 0.07% to 0.1%, from 0.075% to 0.1%, from 0.08% to 0.1%, from 0.085% to 0.1%, from 0.09% to 0.1%, from 0.095% to 0.1%, from 0.001% to 0.095%, from 0.005% to 0.095%, from 0.01% to 0.095%, from 0.015% to 0.095%, from 0.02% to 0.095%, from 0.025% to 0.095%, from 0.03% to 0.095%, from 0.035% to 0.095%, from 0.04% to 0.095%, from 0.045% to 0.095%, from 0.05% to 0.095%, from 0.055% to 0.095%, from 0.06% to 0.095%, from 0.065% to 0.095%, from 0.07% to 0.095%, from 0.075% to 0.095%, from 0.08% to 0.095%, from 0.085% to 0.095%, from 0.09% to 0.095%, from 0.001% to 0.09%, from 0.005% to 0.09%, from 0.01% to 0.09%, from 0.015% to 0.09%, from 0.02% to 0.09%, from 0.025% to 0.09%, from 0.03% to 0.09%, from 0.035% to 0.09%, from 0.04% to 0.09%, from 0.045% to 0.09%, from 0.05% to 0.09%, from 0.055% to 0.09%, from 0.06% to 0.09%, from 0.065% to 0.09%, from 0.07% to 0.09%, from 0.075% to 0.09%, from 0.08% to 0.09%, from 0.085% to 0.09%, from 0.001% to 0.085%, from 0.005% to 0.085%, from 0.01% to 0.085%, from 0.015% to 0.085%, from 0.02% to 0.085%, from 0.025% to 0.085%, from 0.03% to 0.085%, from 0.035% to 0.085%, from 0.04% to 0.085%, from 0.045% to 0.085%, from 0.05% to 0.085%, from 0.055% to 0.085%, from 0.06% to 0.085%, from 0.065% to 0.085%, from 0.07% to 0.085%, from 0.075% to 0.085%, from 0.08% to 0.085%, from 0.001% to 0.08%, from 0.005% to 0.08%, from 0.01% to 0.08%, from 0.015% to 0.08%, from 0.02% to 0.08%, from 0.025% to 0.08%, from 0.03% to 0.08%, from 0.035% to 0.08%, from 0.04% to 0.08%, from 0.045% to 0.08%, from 0.05% to 0.08%, from 0.055% to 0.08%, from 0.06% to 0.08%, from 0.065% to 0.08%, from 0.07% to 0.08%, from 0.075% to 0.08%, from 0.001% to 0.075%, from 0.005% to 0.075%, from 0.01% to 0.075%, from 0.015% to 0.075%, from 0.02% to 0.075%, from 0.025% to 0.075%, from 0.03% to 0.075%, from 0.035% to 0.075%, from 0.04% to 0.075%, from 0.045% to 0.075%, from 0.05% to 0.075%, from 0.055% to 0.075%, from 0.06% to 0.075%, from 0.065% to 0.075%, from 0.07% to 0.075%, from 0.001% to 0.07%, from 0.005% to 0.07%, from 0.01% to 0.07%, from 0.015% to 0.07%, from 0.02% to 0.07%, from 0.025% to 0.07%, from 0.03% to 0.07%, from 0.035% to 0.07%, from 0.04% to 0.07%, from 0.045% to 0.07%, from 0.05% to 0.07%, from 0.055% to 0.07%, from 0.06% to 0.07%, from 0.065% to 0.07, from 0.001% to 0.065%, from 0.005% to 0.065%, from 0.01% to 0.065%, from 0.015% to 0.065%, from 0.02% to 0.065%, from 0.025% to 0.065%, from 0.03% to 0.065%, from 0.035% to 0.065%, from 0.04% to 0.065%, from 0.045% to 0.065%, from 0.05% to 0.065%, from 0.055% to 0.065%, from 0.06% to 0.065%, from 0.001% to 0.06%, from 0.005% to 0.06%, from 0.01% to 0.06%, from 0.015% to 0.06%, from 0.02% to 0.06%, from 0.025% to 0.06%, from 0.03% to 0.06%, from 0.035% to 0.06%, from 0.04% to 0.06%, from 0.045% to 0.06%, from 0.05% to 0.06%, from 0.055% to 0.06%, from 0.001% to 0.055%, from 0.005% to 0.055%, from 0.01% to 0.055%, from 0.015% to 0.055%, from 0.02% to 0.055%, from 0.025% to 0.055%, from 0.03% to 0.055%, from 0.035% to 0.055%, from 0.04% to 0.055%, from 0.045% to 0.055%, from 0.05% to 0.055%, from 0.001% to 0.05%, from 0.005% to 0.05%, from 0.01% to 0.05%, from 0.015% to 0.05%, from 0.02% to 0.05%, from 0.025% to 0.05%, from 0.03% to 0.05%, from 0.035% to 0.05%, from 0.04% to 0.05%, from 0.045% to 0.05%, from 0.001% to 0.045%, from 0.005% to 0.045%, from 0.01% to 0.045%, from 0.015% to 0.045%, from 0.02% to 0.045%, from 0.025% to 0.045%, from 0.03% to 0.045%, from 0.035% to 0.045%, from 0.04% to 0.045%, from 0.001% to 0.04%, from 0.005% to 0.04%, from 0.01% to 0.04%, from 0.015% to 0.04%, from 0.02% to 0.04%, from 0.025% to 0.04%, from 0.03% to 0.04%, from 0.035% to 0.04%, from 0.001% to 0.035%, from 0.005% to 0.035%, from 0.01% to 0.035%, from 0.015% to 0.035%, from 0.02% to 0.035%, from 0.025% to 0.035%, from 0.03% to 0.035%, from 0.001% to 0.03%, from 0.005% to 0.03%, from 0.01% to 0.03%, from 0.015% to 0.03%, from 0.02% to 0.03%, from 0.025% to 0.03%, from 0.001% to 0.025%, from 0.005% to 0.025%, from 0.01% to 0.025%, from 0.015% to 0.025%, from 0.02% to 0.025%, from 0.001% to 0.02%, from 0.005% to 0.02%, from 0.01% to 0.02%, from 0.015% to 0.02%, from 0.001% to 0.015%, from 0.005% to 0.015%, from 0.01% to 0.015%, from 0.001% to 0.01%, from 0.005% to 0.01%, or from 0.001% to 0.005%.

[0053] In the case of a 5xxx aluminum alloy, the amount of magnesium that the alloy may contain may range from 3% to 10% by weight. In some embodiments, the weight percent of magnesium may be from 3% to 10%, from 3.5% to 10%, from 4% to 10%, from 4.5% to 10%, from 5% to 10%, from 5.5% to 10%, from 6% to 10%, from 6.5% to 10%, from 7% to 10%, from 7.5% to 10%, from 8% to 10%, from 8.5% to 10%, from 9% to 10%, from 9.5% to 10%, from 3% to 9.5%, from 3.5% to 9.5%, from 4% to 9.5%, from 4.5% to 9.5%, from 5% to 9.5%, from 5.5% to 9.5%, from 6% to 9.5%, from 6.5% to 9.5%, from 7% to 9.5%, from 7.5% to 9.5%, from 8% to 9.5%, from 8.5% to 9.5%, from 9% to 9.5%, from 3% to 9%, from 3.5% to 9%, from 4% to 9%, from 4.5% to 9%, from 5% to 9%, from 5.5% to 9%, from 6% to 9%, from 6.5% to 9%, from 7% to 9%, from 7.5% to 9%, from 8% to 9%, from 8.5% to 9%, from 3% to 8.5%, from 3.5% to 8.5%, from 4% to 8.5%, from 4.5% to 8.5%, from 5% to 8.5%, from 5.5% to 8.5%, from 6% to 8.5%, from 6.5% to 8.5%, from 7% to 8.5%, from 7.5% to 8.5%, from 8% to 8.5%, from 3% to 8%, from 3.5% to 8%, from 4% to 8%, from 4.5% to 8%, from 5% to 8%, from 5.5% to 8%, from 6% to 8%, from 6.5% to 8%, from 7% to 8%, from 7.5% to 8%, from 3% to 7.5%, from 3.5% to 7.5%, from 4% to 7.5%, from 4.5% to 7.5%, from 5% to 7.5%, from 5.5% to 7.5%, from 6% to 7.5%, from 6.5% to 7.5%, from 7% to 7.5%, from 3% to 7%, from 3.5% to 7%, from 4% to 7%, from 4.5% to 7%, from 5% to 7%, from 5.5% to 7%, from 6% to 7%, from 6.5% to 7%, from 3% to 6.5%, from 3.5% to 6.5%, from 4% to 6.5%, from 4.5% to 6.5%, from 5% to 6.5%, from 5.5% to 6.5%, from 6% to 6.5%, from 3% to 6%, from 3.5% to 6%, from 4% to 6%, from 4.5% to 6%, from 5% to 6%, from 5.5% to 6%, from 3% to 5.5%, from 3.5% to 5.5%, from 4% to 5.5%, from 4.5% to 5.5%, from 5% to 5.5%, from 3% to 5%, from 3.5% to 5%, from 4% to 5%, from 4.5% to 5%, from 3% to 4.5%, from 3.5% to 4.5%, from 4% to 4.5%, from 3% to 4%, from 3.5% to 4%, or from 3% to 3.5%.

[0054] In the case of a 7xxx aluminum alloy, the amount of a combined amount of zinc, magnesium, and copper that the alloy may contain may range from 6% to 15% by weight. In some embodiments, the combined weight percent of zinc, magnesium, and copper may be from 6% to 15%, from 6% to 14.5%, from 6% to 14%, from 6% to 13.5%, from 6% to 13%, from 6% to 12.5%, from 6% to 12%, from 6% to 11.5%, from 6% to 11%, from 6% to 10.5%, from 6% to 10%, from 6% to 9.5%, from 6% to 9%, from 6% to 8.5%, from 6% to 8%, from 6% to 7.5%, from 6% to 7%, from 6% to 6.5%, from 6.5% to 15%, from 6.5% to 14.5%, from 6.5% to 14%, from 6.5% to 13.5%, from 6.5% to 13%, from 6.5% to 12.5%, from 6.5% to 12%, from 6.5% to 11.5%, from 6.5% to 11%, from 6.5% to 10.5%, from 6.5% to 10%, from 6.5% to 9.5%, from 6.5% to 9%, from 6.5% to 8.5%, from 6.5% to 8%, from 6.5% to 7.5%, from 6.5% to 7%, from 7% to 15%, from 7% to 14.5%, from 7% to 14%, from 7% to 13.5%, from 7% to 13%, from 7% to 12.5%, from 7% to 12%, from 7% to 11.5%, from 7% to 11%, from 7% to 10.5%, from 7% to 10%, from 7% to 9.5%, from 7% to 9%, from 7% to 8.5%, from 7% to 8%, from 7% to 7.5%, from 7.5% to 15%, from 7.5% to 14.5%, from 7.5% to 14%, from 7.5% to 13.5%, from 7.5% to 13%, from 7.5% to 12.5%, from 7.5% to 12%, from 7.5% to 11.5%, from 7.5% to 11%, from 7.5% to 10.5%, from 7.5% to 10%, from 7.5% to 9.5%, from 7.5% to 9%, from 7.5% to 8.5%, from 7.5% to 8%, from 8% to 15%, from 8% to 14.5%, from 8% to 14%, from 8% to 13.5%, from 8% to 13%, from 8% to 12.5%, from 8% to 12%, from 8% to 11.5%, from 8% to 11%, from 8% to 10.5%, from 8% to 10%, from 8% to 9.5%, from 8% to 9%, from 8% to 8.5%, from 8.5% to 15%, from 8.5% to 14.5%, from 8.5% to 14%, from 8.5% to 13.5%, from 8.5% to 13%, from 8.5% to 12.5%, from 8.5% to 12%, from 8.5% to 11.5%, from 8.5% to 11%, from 8.5% to 10.5%, from 8.5% to 10%, from 8.5% to 9.5%, from 8.5% to 9%, from 9% to 15%, from 9% to 14.5%, from 9% to 14%, from 9% to 13.5%, from 9% to 13%, from 9% to 12.5%, from 9% to 12%, from 9% to 11.5%, from 9% to 11%, from 9% to 10.5%, from 9% to 10%, from 9% to 9.5%, from 9.5% to 15%, from 9.5% to 14.5%, from 9.5% to 14%, from 9.5% to 13.5%, from 9.5% to 13%, from 9.5% to 12.5%, from 9.5% to 12%, from 9.5% to 11.5%, from 9.5% to 11%, from 9.5% to 10.5%, from 9.5% to 10%, from 10% to 15%, from 10% to 14.5%, from 10% to 14%, from 10% to 13.5%, from 10% to 13%, from 10% to 12.5%, from 10% to 12%, from 10% to 11.5%, from 10% to 11%, from 10% to 10.5%, from 10.5% to 15%, from 10.5% to 14.5%, from 10.5% to 14%, from 10.5% to 13.5%, from 10.5% to 13%, from 10.5% to 12.5%, from 10.5% to 12%, from 10.5% to 11.5%, from 10.5% to 11%, from 11% to 15%, from 11% to 14.5%, from 11% to 14%, from 11% to 13.5%, from 11% to 13%, from 11% to 12.5%, from 11% to 12%, from 11% to 11.5%, from 11.5% to 15%, from 11.5% to 14.5%, from 11.5% to 14%, from 11.5% to 13.5%, from 11.5% to 13%, from 11.5% to 12.5%, from 11.5% to 12%, from 12% to 15%, from 12% to 14.5%, from 12% to 14%, from 12% to 13.5%, from 12% to 13%, from 12% to 12.5%, from 12.5% to 15%, from 12.5% to 14.5%, from 12.5% to 14%, from 12.5% to 13.5%, from 12.5% to 13%, from 13% to 15%, from 13% to 14.5%, from 13% to 14%, from 13% to 13.5%, from 13.5% to 15%, from 13.5% to 14.5%, from 13.5% to 14%, from 14% to 15%, from 14% to 14.5%, or from 14.5% to 15%.

[0055] As discussed above, when the magnesium-strengthened aluminum alloy contains 3 wt. % or more magnesium in the case of a 5xxx aluminum alloy or 6 wt. % or more zinc, magnesium, and copper combined in the case of a 7xxx aluminum alloy, the alloy may be more prone to stress corrosion cracking. A magnesium-strengthened aluminum alloy that contains less than 3 wt. % magnesium or less than 6 wt. % of zinc, magnesium, and copper combined may nonetheless also be susceptible to stress corrosion cracking. Accordingly, calcium, strontium, and/or silver may also be added to magnesium-strengthened aluminum alloys having less than 3 wt. % magnesium or less than 6 wt. % of zinc, magnesium, and copper combined to suppress stress corrosion cracking, especially when the product may be exposed to corrosive environments, such as a marine environment. For example, the amount of magnesium that the 5xxx aluminum alloy may contain may range from 0.1% to 3% by weight. In some embodiments, the weight percent of magnesium that the 5xxx alloy may contain may range from 0.1% to 1.5%, from 0.1% to 1.5%, from 0.5% to 1.5%, from 1% to 1.5%, from 0.1% to 1%, from 0.5% to 1%, or from 1.5% to 3%. Optionally, the amount of magnesium may be from 1.5% to 3%, from 1.6% to 3%, from 1.7% to 3%, from 1.8% to 3%, from 1.9% to 3%, from 2% to 3%, from 2.1% to 3%, from 2.2% to 3%, from 2.3% to 3%, from 2.4% to 3%, from 2.5% to 3%, from 2.6% to 3%, from 2.7% to 3%, from 2.8% to 3%, from 2.9% to 3%, from 1.5% to 2.9%, from 1.6% to 2.9%, from 1.7% to 2.9%, from 1.8% to 2.9%, from 1.9% to 2.9%, from 2% to 2.9%, from 2.1% to 2.9%, from 2.2% to 2.9%, from 2.3% to 2.9%, from 2.4% to 2.9%, from 2.5% to 2.9%, from 2.6% to 2.9%, from 2.7% to 2.9%, from 2.8% to 2.9%, from 1.5% to 2.8%, from 1.6% to 2.8%, from 1.7% to 2.8%, from 1.8% to 2.8%, from 1.9% to 2.8%, from 2% to 2.8%, from 2.1% to 2.8%, from 2.2% to 2.8%, from 2.3% to 2.8%, from 2.4% to 2.8%, from 2.5% to 2.8%, from 2.6% to 2.8%, from 2.7% to 2.8%, from 1.5% to 2.7%, from 1.6% to 2.7%, from 1.7% to 2.7%, from 1.8% to 2.7%, from 1.9% to 2.7%, from 2% to 2.7%, from 2.1% to 2.7%, from 2.2% to 2.7%, from 2.3% to 2.7%, from 2.4% to 2.7%, from 2.5% to 2.7%, from 2.6% to 2.7%, from 1.5% to 2.6%, from 1.6% to 2.6%, from 1.7% to 2.6%, from 1.8% to 2.6%, from 1.9% to 2.6%, from 2% to 2.6%, from 2.1% to 2.6%, from 2.2% to 2.6%, from 2.3% to 2.6%, from 2.4% to 2.6%, from 2.5% to 2.6%, from 1.5% to 2.5%, from 1.6% to 2.5%, from 1.7% to 2.5%, from 1.8% to 2.5%, from 1.9% to 2.5%, from 2% to 2.5%, from 2.1% to 2.5%, from 2.2% to 2.5%, from 2.3% to 2.5%, from 2.4% to 2.5%, from 1.5% to 2.4%, from 1.6% to 2.4%, from 1.7% to 2.4%, from 1.8% to 2.4%, from 1.9% to 2.4%, from 2% to 2.4%, from 2.1% to 2.4%, from 2.2% to 2.4%, from 2.3% to 2.4%, from 1.5% to 2.3%, from 1.6% to 2.3%, from 1.7% to 2.3%, from 1.8% to 2.3%, from 1.9% to 2.3%, from 2% to 2.3%, from 2.1% to 2.3%, from 2.2% to 2.3%, from 1.5% to 2.2%, from 1.6% to 2.2%, from 1.7% to 2.2%, from 1.8% to 2.2%, from 1.9% to 2.2%, from 2% to 2.2%, from 2.1% to 2.2%, from 1.5% to 2.1%, from 1.6% to 2.1%, from 1.7% to 2.1%, from 1.8% to 2.1%, from 1.9% to 2.1%, from 2% to 2.1%, from 1.5% to 2%, from 1.6% to 2%, from 1.7% to 2%, from 1.8% to 2%, from 1.9% to 2%, from 1.5% to 1.9%, from 1.6% to 1.9%, from 1.7% to 1.9%, from 1.8% to 1.9%, from 1.5% to 1.8%, from 1.6% to 1.8%, from 1.7% to 1.8%, from 1.5% to 1.7%, from 1.6% to 1.7%, or from 1.5% to 1.6%. For example, the combined amount of zinc, magnesium, and copper that the 7xxx aluminum alloy may contain may range from 0.5% to 6% by weight. In some embodiments, the combined weight percent of zinc, magnesium, and copper that the 7xxx aluminum alloy may contain may range from 0.5% to 6%, from 0.5% to 5.5%, from 0.5% to 5%, from 0.5% to 4.5%, from 0.5% to 4%, from 0.5% to 3.5%, from 0.5% to 3%, from 0.5% to 2.5%, from 0.5% to 2%, from 0.5% to 1.5%, from 0.5% to 1%, from 1% to 6%, from 1% to 5.5%, from 1% to 5%, from 1% to 4.5%, from 1% to 4%, from 1% to 3.5%, from 1% to 3%, from 1% to 2.5%, from 1% to 2%, from 1% to 1.5%, from 1.5% to 6%, from 1.5% to 5.5%, from 1.5% to 5%, from 1.5% to 4.5%, from 1.5% to 4%, from 1.5% to 3.5%, from 1.5% to 3%, from 1.5% to 2.5%, from 1.5% to 2%, from 2% to 6%, from 2% to 5.5%, from 2% to 5%, from 2% to 4.5%, from 2% to 4%, from 2% to 3.5%, from 2% to 3%, from 2% to 2.5%, from 2.5% to 6%, from 2.5% to 5.5%, from 2.5% to 5%, from 2.5% to 4.5%, from 2.5% to 4%, from 2.5% to 3.5%, from 2.5% to 3%, from 3% to 6%, from 3% to 5.5%, from 3% to 5%, from 3% to 4.5%, from 3% to 4%, from 3% to 3.5%, from 3.5% to 6%, from 3.5% to 5.5%, from 3.5% to 5%, from 3.5% to 4.5%, from 3.5% to 4%, from 4% to 6%, from 4% to 5.5%, from 4% to 5%, from 4% to 4.5%, from 4.5% to 6%, from 4.5% to 5.5%, from 4.5% to 5%, from 5% to 6%, from 5% to 5.5%, or from 5.5% to 6%.

[0056] Depending on the amount of magnesium in the 5xxx aluminum alloy or the combined amount of zinc, magnesium, and copper in the 7xxx aluminum alloy, the amount of calcium that may be added to effectively suppress stress corrosion cracking may vary. For example, a ratio of the amount of calcium to the amount of magnesium in the 5xxx alloy may range from about 0.0001 to about 1. Optionally a ratio of the amount of calcium in the alloy to the amount of magnesium in the alloy may range from 0.0001 to 1, from 0.0001 to 0.1, from 0.0001 to 0.01, from 0.0001 to 0.001, from 0.001 to 1, from 0.001 to 0.1, from 0.001 to 0.01, from 0.01 to 1, from 0.01 to 0.1, or from 0.1 to 1. A ratio of the amount of calcium to the combined amount of zinc, magnesium, and copper in the 7xxx alloy may range from about 0.0001 to about 1. Optionally a ratio of the amount of calcium in the alloy to the combined amount of zinc, magnesium, and copper in the alloy may range from 0.0001 to 1, from 0.0001 to 0.1, from 0.0001 to 0.01, from 0.0001 to 0.001, from 0.001 to 1, from 0.001 to 0.1, from 0.001 to 0.01, from 0.01 to 1, from 0.01 to 0.1, or from 0.1 to 1.

[0057] Depending on the amount of magnesium in the 5xxx aluminum alloy or the combined amount of zinc, magnesium, and copper in the 7xxx aluminum alloy, the amount of strontium that may be added to effectively suppress stress corrosion cracking may vary. For example, a ratio of the amount of strontium to the amount of magnesium in the 5xxx alloy may range from about 0.0001 to about 1. Optionally a ratio of the amount of strontium in the alloy to the amount of magnesium in the alloy may range from 0.0001 to 1, from 0.0001 to 0.1, from 0.0001 to 0.01, from 0.0001 to 0.001, from 0.001 to 1, from 0.001 to 0.1, from 0.001 to 0.01, from 0.01 to 1, from 0.01 to 0.1, or from 0.1 to 1. A ratio of the amount of strontium to the combined amount of zinc, magnesium, and copper in the 7xxx alloy may range from about 0.0001 to about 1. Optionally a ratio of the amount of strontium in the alloy to the combined amount of zinc, magnesium, and copper in the alloy may range from 0.0001 to 1, from 0.0001 to 0.1, from 0.0001 to 0.01, from 0.0001 to 0.001, from 0.001 to 1, from 0.001 to 0.1, from 0.001 to 0.01, from 0.01 to 1, from 0.01 to 0.1, or from 0.1 to 1. [0058] Depending on the amount of magnesium in the 5xxx aluminum alloy or the combined amount of zinc, magnesium, and copper in the 7xxx aluminum alloy, the amount of silver that may be added to effectively suppress stress corrosion cracking may vary. For example, a ratio of the amount of silver to the amount of magnesium in the 5xxx alloy may range from about 0.0001 to about 1. Optionally a ratio of the amount of silver in the alloy to the amount of magnesium in the alloy may range from 0.0001 to 1, from 0.0001 to 0.1, from 0.0001 to 0.01, from 0.0001 to 0.001, from 0.001 to 1, from 0.001 to 0.1, from 0.001 to 0.01, from 0.01 to 1, from 0.01 to 0.1, or from 0.1 to 1. A ratio of the amount of silver to the combined amount of zinc, magnesium, and copper in the 7xxx alloy may range from about 0.0001 to about 1. Optionally a ratio of the amount of silver in the alloy to the combined amount of zinc, magnesium, and copper in the alloy may range from 0.0001 to 1, from 0.0001 to 0.1, from 0.0001 to 0.01, from 0.0001 to 0.001, from 0.001 to 1, from 0.001 to 0.1, from 0.001 to 0.01, from 0.01 to 1, from 0.01 to 0.1, or from 0.1 to 1.

[0059] In some embodiments, the amount of zinc that the alloy may contain may range from 0.01% to 15% by weight. In some embodiments, the amount of zinc that the alloy may contain may range from 0.01% to 8% by weight. For example, the weight percent of zinc may be from 0.01% to 8%, 0.05% to 8%, from 0.1% to 8%, from 0.5% to 8%, from 1% to 8%, from 1.5% to 8%, from 2% to 8%, from 2.5% to 8%, from 3% to 8%, from 3.5% to 8%, from 4% to 8%, from 4.5% to 8%, from 5% to 8%, from 5.5% to 8%, from 6% to 8%, from 6.5% to 8%, from 7% to 8%, from 7.5% to 8%, from 0.01% to 7.5%, 0.05% to 7.5%, from 0.1% to 7.5%, from 0.5% to 7.5%, from 1% to 7.5%, from 1.5% to 7.5%, from 2% to 7.5%, from 2.5% to 7.5%, from 3% to 7.5%, from 3.5% to 7.5%, from 4% to 7.5%, from 4.5% to 7.5%, from 5% to 7.5%, from 5.5% to 7.5%, from 6% to 7.5%, from 6.5% to 7.5%, from 7% to 7.5%, from 0.01% to 7%, 0.05% to 7%, from 0.1% to 7%, from 0.5% to 7%, from 1% to 7%, from 1.5% to 7%, from 2% to 7%, from 2.5% to 7%, from 3% to 7%, from 3.5% to 7%, from 4% to 7%, from 4.5% to 7%, from 5% to 7%, from 5.5% to 7%, from 6% to 7%, from 6.5% to 7%, from 0.01% to 6.5%, 0.05% to 6.5%, from 0.1% to 6.5%, from 0.5% to 6.5%, from 1% to 6.5%, from 1.5% to 6.5%, from 2% to 6.5%, from 2.5% to 6.5%, from 3% to 6.5%, from 3.5% to 6.5%, from 4% to 6.5%, from 4.5% to 6.5%, from 5% to 6.5%, from 5.5% to 6.5%, from 6% to 6.5%, from 0.01% to 6%, 0.05% to 6%, from 0.1% to 6%, from 0.5% to 6%, from 1% to 6%, from 1.5% to 6%, from 2% to 6%, from 2.5% to 6%, from 3% to 6%, from 3.5% to 6%, from 4% to 6%, from 4.5% to 6%, from 5% to 6%, from 5.5% to 6%, from 0.01% to 5.5%, 0.05% to 5.5%, from 0.1% to 5.5%, from 0.5% to 5.5%, from 1% to 5.5%, from 1.5% to 5.5%, from 2% to 5.5%, from 2.5% to 5.5%, from 3% to 5.5%, from 3.5% to 5.5%, from 4% to 5.5%, from 4.5% to 5.5%, from 5% to 5.5%, from 0.01% to 5%, 0.05% to 5%, from 0.1% to 5%, from 0.5% to 5%, from 1% to 5%, from 1.5% to 5%, from 2% to 5%, from 2.5% to 5%, from 3% to 5%, from 3.5% to 5%, from 4% to 5%, from 4.5% to 5%, from 0.01% to 4.5%, 0.05% to 4.5%, from 0.1% to 4.5%, from 0.5% to 4.5%, from 1% to 4.5%, from 1.5% to 4.5%, from 2% to 4.5%, from 2.5% to 4.5%, from 3% to 4.5%, from 3.5% to 4.5%, from 4% to 4.5%, from 0.01% to 4%, 0.05% to 4%, from 0.1% to 4%, from 0.5% to 4%, from 1% to 4%, from 1.5% to 4%, from 2% to 4%, from 2.5% to 4%, from 3% to 4%, from 3.5% to 4%, from 0.01% to 3.5%, 0.05% to 3.5%, from 0.1% to 3.5%, from 0.5% to 3.5%, from 1% to 3.5%, from 1.5% to 3.5%, from 2% to 3.5%, from 2.5% to 3.5%, from 3% to 3.5%, from 0.01% to 3%, 0.05% to 3%, from 0.1% to 3%, from 0.5% to 3%, from 1% to 3%, from 1.5% to 3%, from 2% to 3%, from 2.5% to 3%, from 0.01% to 2.5%, 0.05% to 2.5%, from 0.1% to 2.5%, from 0.5% to 2.5%, from 1% to 2.5%, from 1.5% to 2.5%, from 2% to 2.5%, from 0.01% to 2%, 0.05% to 2%, from 0.1% to 2%, from 0.5% to 2%, from 1% to 2%, from 1.5% to 2%, from 0.01% to 1.5%, 0.05% to 1.5%, from 0.1% to 1.5%, from 0.5% to 1.5%, from 1% to 1.5%, from 0.01% to 1%, 0.05% to 1%, from 0.1% to 1%, from 0.5% to 1%, from 0.01% to 0.5%, 0.05% to 0.5%, from 0.1% to 0.5%, from 0.01% to 0.1%, 0.05% to 0.1%, or from 0.01% to 0.05%.

[0060] In some embodiments, the amount of zinc that the alloy may contain may range from 8% to 15% by weight. For example, the weight percent of zinc may be from 8% to 15%, from 8.5% to 15%, from 9% to 15%, from 9.5% to 15%, from 10% to 15%, from 10.5% to 15%, from 11% to 15%, from 11.5% to 15%, from 12% to 15%, from 12.5% to 15%, from 13% to 15%, from 13.5% to 15%, from 14% to 15%, from 14.5% to 15%, from 8% to 14.5%, from 8.5% to 14.5%, from 9% to 14.5%, from 9.5% to 14.5%, from 10% to 14.5%, from 10.5% to 14.5%, from 11% to 14.5%, from 11.5% to 14.5%, from 12% to 14.5%, from 12.5% to 14.5%, from 13% to 14.5%, from 13.5% to 14.5%, from 14% to 14.5%, from 8% to 14%, from 8.5% to 14%, from 9% to 14%, from 9.5% to 14%, from 10% to 14%, from 10.5% to 14%, from 11% to 14%, from 11.5% to 14%, from 12% to 14%, from 12.5% to 14%, from 13% to 14%, from 13.5% to 14%, from 8% to 13.5%, from 8.5% to 13.5%, from 9% to 13.5%, from 9.5% to 13.5%, from 10% to 13.5%, from 10.5% to 13.5%, from 11% to 13.5%, from 11.5% to 13.5%, from 12% to 13.5%, from 12.5% to 13.5%, from 13% to 13.5%, from 8% to 13%, from 8.5% to 13%, from 9% to 13%, from 9.5% to 13%, from 10% to 13%, from 10.5% to 13%, from 11% to 13%, from 11.5% to 13%, from 12% to 13%, from 12.5% to 13%, from 8% to 12.5%, from 8.5% to 12.5%, from 9% to 12.5%, from 9.5% to 12.5%, from 10% to 12.5%, from 10.5% to 12.5%, from 11% to 12.5%, from 11.5% to 12.5%, from 12% to 12.5%, from 8% to 12%, from 8.5% to 12%, from 9% to 12%, from 9.5% to 12%, from 10% to 12%, from 10.5% to 12%, from 11% to 12%, from 11.5% to 12%, from 8% to 11.5%, from 8.5% to 11.5%, from 9% to 11.5%, from 9.5% to 11.5%, from 10% to 11.5%, from 10.5% to 11.5%, from 11% to 11.5%, from 8% to 11%, from 8.5% to 11%, from 9% to 11%, from 9.5% to 11%, from 10% to 11%, from 10.5% to 11%, from 8% to 10%, from 8.5% to 10%, from 9% to 10%, from 9.5% to 10%, from 8% to 9.5%, from 8.5% to 9.5%, from 9% to 9.5%, from 8% to 9%, from 8.5% to 9%, or from 8% to 8.5%.

[0061] In some embodiments, the alloy may not include zinc as an alloying element, and only may include zinc as an incidental element or unavoidable impurity.

[0062] As mentioned above, the aluminum alloy families that may be more susceptible to stress corrosion cracking as compared to other aluminum alloys may include the 5xxx series and the 7xxx series.

[0063] FIG. 2 provides an overview of an exemplary method of making an aluminum alloy product. The method of FIG. 2 begins at step 205 where molten aluminum alloy 206 is cast to form a cast aluminum alloy product 207, such as an ingot or other cast product. Although FIG. 2 depicts a schematic illustration of a direct chill casting process, the aluminum alloys described herein can also be cast using a continuous casting process. A continuous casting system can include a pair of moving opposed casting surfaces (e.g., moving opposed belts, rolls, or blocks), a casting cavity between the pair of moving opposed casting surfaces, and a molten metal injector. The molten metal injector can have an end opening from which molten metal can exit the molten metal injector and be injected into the casting cavity.

[0064] The molten aluminum alloy 206 may include molten aluminum, magnesium, and calcium and optionally strontium or silver. In some embodiments, the molten aluminum alloy 206 may further include zinc. The amount (by weight percentage) of magnesium, calcium, and zinc, respectively, may be any of the various amounts discussed above or a subrange thereof. Depending on the application, the molten aluminum alloy 206 may further include one or more other alloying elements, e.g., manganese, zirconium, scandium, silicon, iron, copper, chromium, titanium, etc.

[0065] The cast aluminum alloy product 207 may then be processed by any suitable means. As discussed above, heat treatment for conventional magnesium-strengthened aluminum alloys may be avoided or may require close control, if performed, so as to limit the formation of the magnesium-containing precipitates, which eventually may lead to stress corrosion cracking. Accordingly, conventional magnesium-strengthened aluminum alloys are typically work hardened and are in an H condition or temper. In contrast, when calcium is added to the magnesium-strengthened aluminum alloy as disclosed herein, the alloy may be significantly less susceptible to stress corrosion cracking as discussed above. Accordingly, the magnesium-strengthened aluminum alloy including calcium as an alloying element may be work hardened and/or heat treated. The resultant alloy may be in an H temper or T temper, as appropriate. Suitable H tempers may include H1X, H2X, H3X, H4X, or the like, such as HI 11, HI 12, HI 15, HI 16, H12, H14, H16, H18, H19, H24, H26, H28, H32, H321, H323, H34, H343, H36, H38, etc. Suitable T tempers may include Tl, T2, T3, T351, T352, T3510, T3511, T36, T361, T4, T42, T451, T4510, T4511, T5, T6, T62, T651, T6510, T6511, T7, T72, T73, T7351, T8, T81, T851, T8510, T8511, T9, T10, etc. Exemplary processing steps may include homogenization, hot rolling, cold rolling, annealing, solution heat treatment, pre-aging, or the like.

[0066] Some exemplary processing steps are shown in FIG. 2. At step 210, the cast aluminum alloy product 207 is homogenized to form a homogenized aluminum alloy product 211. In the homogenization step, the cast product 207 described herein may be heated, such as to a temperature ranging from about 400 °C to about 500 °C. For example, the product 207 can be heated to 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, about 480 °C, about 490 °C, or about 500 °C. The product 207 is then allowed to soak (i.e., held at the indicated temperature) for a period of time. In some examples, the total time for the homogenization step, including the heating and soaking phases, can be up to 24 hours. For example, the product 207 can be heated up to 500 °C and soaked, for a total time of up to 18 hours for the homogenization step. Optionally, the product 207 can be heated to below 490 °C and soaked, for a total time of greater than 18 hours for the homogenization step. In some cases, the homogenization step comprises multiple processes. In some non-limiting examples, the homogenization step includes heating the product 207 to a first temperature for a first period of time followed by heating to a second temperature for a second period of time. For example, the product 207 can be heated to about 465 °C for about 3.5 hours and then heated to about 480 °C for about 6 hours.

[0067] Following the homogenization step, at step 215, the homogenized aluminum alloy product 211 is subjected to one or more rolling passes to form a rolled aluminum alloy product 212, which may correspond to an aluminum alloy article, such as an aluminum alloy plate, an aluminum alloy shate, or an aluminum alloy sheet that is coiled after rolling. [0068] In the case where a hot rolling step is performed, prior to hot rolling, the homogenized product 211 can be allowed to cool to a temperature such as between 300 °C to 450 °C. For example, the homogenized product 211 can be allowed to cool to a temperature of between 325 °C to 425 °C or from 350 °C to 400 °C. In some embodiments, the cast product can be a continuously cast product that can be allowed to cool to a temperature between 300 °C to 450 °C. The product can then be hot rolled at a suitable temperature, such as between 300 °C to 450 °C, to form a hot rolled intermediate product such as a hot rolled plate, a hot rolled shate or a hot rolled sheet having a gauge between 3 mm and 200 mm (e.g., 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm, 95 mm, 100 mm, 110 mm, 120 mm, 130 mm, 140 mm, 150 mm, 160 mm, 170 mm, 180 mm, 190 mm, 200 mm, or anywhere in between). During hot rolling, temperatures and other operating parameters can be controlled so that the temperature of the hot rolled intermediate product upon exit from the hot rolling mill is no more than 470 °C, no more than 450 °C, no more than 440 °C, or no more than 430 °C.

[0069] The hot rolled product can then be cold rolled into a cold rolled product having a gauge between about 0.5 to 10 mm, e.g., between about 0.7 to 6.5 mm. Optionally, the cold rolled sheet can have a gauge of 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, or 10.0 mm. The cold rolling can be performed to result in a final gauge thickness that represents a gauge reduction of up to 85 % (e.g., up to 10 %, up to 20 %, up to 30 %, up to 40 %, up to 50 %, up to 60 %, up to 70 %, up to 80 %, or up to 85 % reduction) as compared to the hot rolled product. In some embodiments, an interannealing step can be performed during the cold rolling step. The interannealing step can be performed at a temperature of from about 300 °C to about 450 °C (e.g., about 310 °C, about 320 °C, about 330 °C, about 340 °C, about 350 °C, about 360 °C, about 370 °C, about 380 °C, about 390 °C, about 400 °C, about 410 °C, about 420 °C, about 430 °C, about 440 °C, or about 450 °C). In some cases, the interannealing step comprises multiple processes. In some non-limiting examples, the interannealing step includes heating the cold rolled product to a first temperature for a first period of time followed by heating to a second temperature for a second period of time. For example, the cold rolled product can be heated to about 410 °C for about 1 hour and then heated to about 330 °C for about 2 hours.

[0070] In some embodiments, a rolled product can undergo a solution heat treatment step. The solution heat treatment step can be any treatment for the sheet which results in solutionizing of the soluble particles. Because the magnesium-strengthened aluminum alloy with added calcium may be less susceptible to stress corrosion cracking, the solution heat treatment may be omitted. In the case where a solution heat treatment is performed, the rolled product can be heated to a peak metal temperature (PMT) of up to 590 °C (e.g., from 400 °C to 590 °C) and soaked for a period of time at the temperature. For example, the rolled product can be soaked at 480 °C for a soak time of up to 30 minutes (e.g., 0 seconds, 60 seconds, 75 seconds, 90 seconds, 5 minutes, 10 minutes, 20 minutes, 25 minutes, or 30 minutes). After heating and soaking, the product can be rapidly cooled at rates greater than 200 °C/s to a temperature between 500 and 200 °C. In one example, the product is subjected to a quench rate of above 200 °C/second at temperatures between 450 °C and 200 °C. Optionally, the cooling rates can be faster in other cases.

[0071] After quenching, the heat treated product can optionally undergo a pre-aging treatment by reheating the product before coiling. The pre-aging treatment can be performed at a temperature of from about 70 °C to about 125 °C for a period of time of up to 6 hours.

For example, the pre-aging treatment can be performed at a temperature of about 70 °C, about 75 °C, about 80 °C, about 85 °C, about 90 °C, about 95 °C, about 100 °C, about 105 °C, about 110 °C, about 115 °C, about 120 °C, or about 125 °C. In some embodiments, the pre-aging treatment can be performed for about 30 minutes, about 1 hour, about 2 hours, about 3 hours, about 4 hours, about 5 hours, or about 6 hours. The pre-aging treatment can be carried out by passing the plate, shate, or sheet through a heating device, such as a device that emits radiant heat, convective heat, induction heat, infrared heat, or the like.

[0072] The cast products described herein can be used to make products in the form of plates or other suitable products. For example, plates including the products as described herein can be prepared by processing an ingot in a homogenization step or casting a product in a continuous caster followed by a hot rolling step. In the hot rolling step, the cast product can be hot rolled to a 200 mm thick gauge or less (e.g., from about 10 mm to about 200 mm). For example, the cast product can be hot rolled to a plate having a final gauge thickness of about 10 mm to about 175 mm, about 15 mm to about 150 mm, about 20 mm to about 125 mm, about 25 mm to about 100 mm, about 30 mm to about 75 mm, or about 35 mm to about 50 mm.

[0073] As discussed above, the added calcium may alter or limit the formation of magnesium-containing precipitates at the grain boundaries when the magnesium-strengthened aluminum alloy may be subjected to an elevated temperature. Accordingly, in addition to the heat treatment discussed above, the magnesium-strengthened aluminum alloys described herein may be further subjected to an elevated temperature, such as during welding, paint baking, etc., without increasing the risk of or susceptibility to stress corrosion cracking. Depending on the process, the elevated temperature may range from 50 °C to 600 °C. In some embodiments, the elevated temperature may range from 50 °C to 600 °C, 100 °C to 600 °C, 150 °C to 600 °C, 200 °C to 600 °C, 250 °C to 600 °C, 300 °C to 600 °C, 350 °C to 600

°C, 400 °C to 600 °C, 450 °C to 600 °C, 500 °C to 600 °C, 550 °C to 600 °C, 50 °C to 550

°C, 100 °C to 550 °C, 150 °C to 550 °C, 200 °C to 550 °C, 250 °C to 550 °C, 300 °C to 550

°C, 350 °C to 550 °C, 400 °C to 550 °C, 450 °C to 550 °C, 500 °C to 550 °C, 50 °C to 500

°C, 100 °C to 500 °C, 150 °C to 500 °C, 200 °C to 500 °C, 250 °C to 500 °C, 300 °C to 500

°C, 350 °C to 500 °C, 400 °C to 500 °C, 450 °C to 500 °C, 50 °C to 450 °C, 100 °C to 450

°C, 150 °C to 450 °C, 200 °C to 450 °C, 250 °C to 450 °C, 300 °C to 450 °C, 350 °C to 450

°C, 400 °C to 450 °C, 50 °C to 400 °C, 100 °C to 400 °C, 150 °C to 400 °C, 200 °C to 400

°C, 250 °C to 400 °C, 300 °C to 400 °C, 350 °C to 400 °C, 50 °C to 350 °C, 100 °C to 350

°C, 150 °C to 350 °C, 200 °C to 350 °C, 250 °C to 350 °C, 300 °C to 350 °C, 50 °C to 300

°C, 100 °C to 300 °C, 150 °C to 300 °C, 200 °C to 300 °C, 250 °C to 300 °C, 50 °C to 250

°C, 100 °C to 250 °C, 150 °C to 250 °C, 200 °C to 250 °C, 50 °C to 200 °C, 100 °C to 200 °C, 150 °C to 200 °C, 50 °C to 150 °C, 100 °C to 150 °C, or 50 °C to 100 °C.

[0074] Given the suppressing effect of the added calcium on stress corrosion cracking, the magnesium-strengthened aluminum alloy may be used in corrosive environments, such as in the case of marine applications, automotive reinforcement/chassis applications, or the like, with reduced susceptibility to stress corrosion cracking.

[0075] All patents, publications and abstracts cited herein are incorporated herein by reference in their entirety. The foregoing description of the embodiments, including illustrated embodiments, has been presented only for the purpose of illustration and description and is not intended to be exhaustive or limiting to the precise forms disclosed. Numerous modifications, adaptations, and uses thereof will be apparent to those skilled in the art.

ILLUSTRATIVE ASPECTS

[0076] As used below, any reference to a series of aspects is to be understood as a reference to each of those examples disjunctively (e.g., “Aspects 1-4” is to be understood as “Aspects 1, 2, 3, or 4”).

[0077] Aspect l is a stress corrosion cracking -resistant aluminum alloy product, comprising: a plurality of alloying elements, including: 3 wt. % to 10 wt. % magnesium or 6 wt. % to 15 wt. % zinc, magnesium, and copper combined; 0.001 wt. % to 0.1 wt. % calcium; and aluminum.

[0078] Aspect 2 is the stress corrosion cracking -resistant aluminum alloy product of any previous or subsequent aspect, wherein the aluminum constitutes a remainder of the stress corrosion cracking-resistant aluminum alloy product.

[0079] Aspect 3 is the stress corrosion cracking -resistant aluminum alloy product of any previous or subsequent aspect, wherein the plurality of alloying elements further include 0.001 wt. % to 0.1 wt. % strontium.

[0080] Aspect 4 is the stress corrosion cracking -resistant aluminum alloy product of any previous or subsequent aspect, wherein the plurality of alloying elements further include 0.001 wt. % to 0.1 wt. % silver.

[0081] Aspect 5 is the stress corrosion cracking -resistant aluminum alloy product of any previous or subsequent aspect in an H temper.

[0082] Aspect 6 is the stress corrosion cracking -resistant aluminum alloy product of any previous or subsequent aspect in a T temper.

[0083] Aspect 7 is the stress corrosion cracking -resistant aluminum alloy product of any previous or subsequent aspect produced by subjecting a cast aluminum product to one or more hot rolling processes.

[0084] Aspect 8 is the stress corrosion cracking -resistant aluminum alloy product of any previous or subsequent aspect produced by subjecting a cast aluminum product to one or more cold rolling processes.

[0085] Aspect 9 is the stress corrosion cracking -resistant aluminum alloy product of any previous or subsequent aspect, comprising a 5xxx series aluminum alloy.

[0086] Aspect 10 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the plurality of alloying elements does not include zinc.

[0087] Aspect 11 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, comprising a 7xxx series aluminum alloy.

[0088] Aspect 12 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the plurality of alloying elements further comprises zinc.

[0089] Aspect 13 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the plurality of alloying elements comprises 0.1 wt. % to 15 wt. % zinc. [0090] Aspect 14 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, comprising magnesium-containing precipitates.

[0091] Aspect 15 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, comprising magnesium and/or aluminum.

[0092] Aspect 16 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the magnesium-containing precipitates comprise MgsAls beta phase particles, and wherein the stress corrosion cracking-resistant aluminum alloy product comprises less than 0.05 wt. % of the MgsAls beta phase particles.

[0093] Aspect 17 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the magnesium-containing precipitates comprise Mg and/or Zn.

[0094] Aspect 18 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the magnesium-containing precipitates comprise MgZm eta phase particles, and wherein the stress corrosion cracking-resistant aluminum alloy product comprises less than 10 wt. % of the MgZm eta phase particles.

[0095] Aspect 19 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the magnesium-containing precipitates comprise MgZm eta phase particles, and wherein the stress corrosion cracking-resistant aluminum alloy product comprises less than 5 wt. % of the MgZm eta phase particles.

[0096] Aspect 20 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the magnesium-containing precipitates comprise MgZm eta phase particles, and wherein the stress corrosion cracking-resistant aluminum alloy product comprises less than 1 wt. % of the MgZm eta phase particles.

[0097] Aspect 21 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the magnesium-containing precipitates comprise MgZm eta phase particles, and wherein the stress corrosion cracking-resistant aluminum alloy product comprises less than 0.1 wt. % of the MgZm eta phase particles.

[0098] Aspect 22 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the magnesium-containing precipitates comprise MgZm eta phase particles, and wherein the stress corrosion cracking-resistant aluminum alloy product comprises less than 0.05 wt. % of the MgZm eta phase particles.

[0099] Aspect 23 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the magnesium-containing precipitates are formed through exposure to a temperature of from 50 °C to 600 °C. [0100] Aspect 24 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the magnesium-containing precipitates are formed during aging.

[0101] Aspect 25 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the magnesium-containing precipitates comprise calcium.

[0102] Aspect 26 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein a presence of the calcium in the aluminum alloy product reduces an amount of the magnesium-containing precipitates in the stress corrosion cracking-resistant aluminum alloy product as referenced to a comparable aluminum alloy product comprising 3 wt. % to 10 wt. % magnesium or 6 wt. % to 12 wt. % zinc, magnesium, and copper combined, and less than 0.001 wt. % calcium and subjected to identical processing conditions.

[0103] Aspect 27 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, comprising one or more phases containing calcium, strontium, and/or silver at grain boundaries of the aluminum alloy product.

[0104] Aspect 28 is the stress corrosion cracking-resistant aluminum alloy of any previous or subsequent aspect, wherein the one or more phases are produced by exposure to an elevated temperature of from 50 °C to 600 °C.

[0105] Aspect 29 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the one or more phases are produced by aging.

[0106] Aspect 30 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the one or more phases comprises calcium metal. [0107] Aspect 31 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the one or more phases comprises strontium metal. [0108] Aspect 32 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the one or more phases comprises silver metal.

[0109] Aspect 33 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein one phase of the one or more phases comprises calcium and magnesium.

[0110] Aspect 34 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein one phase of the one or more phases comprises strontium and magnesium. [0111] Aspect 35 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein one phase of the one or more phases comprises silver and magnesium.

[0112] Aspect 36 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein one phase of the one or more phases comprises calcium and aluminum.

[0113] Aspect 37 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein one phase of the one or more phases comprises strontium and aluminum.

[0114] Aspect 38 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein one phase of the one or more phases comprises silver and aluminum.

[0115] Aspect 39 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein one phase of the one or more phases comprises calcium, aluminum, and magnesium.

[0116] Aspect 40 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein one phase of the one or more phases comprises strontium, aluminum, and magnesium.

[0117] Aspect 41 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein one phase of the one or more phases comprises calcium, strontium, aluminum, and magnesium.

[0118] Aspect 42 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein one phase of the one or more phases comprises calcium, silver, aluminum, and magnesium.

[0119] Aspect 43 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein one phase of the one or more phases comprises strontium, silver, aluminum, and magnesium.

[0120] Aspect 44 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein one phase of the one or more phases comprises calcium, strontium, silver, aluminum, and magnesium.

[0121] Aspect 45 is the stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect, wherein the one or more phases at least partially surround magnesium-containing precipitates located at the grain boundaries. [0122] Aspect 46 is a method of making a stress corrosion cracking-resistant aluminum alloy product, comprising: providing an aluminum alloy in a molten state as a molten aluminum alloy, wherein the aluminum alloy comprises: 3 wt. % to 10 wt. % magnesium or 6 wt. % to 12 wt. % zinc, magnesium, and copper combined; 0.001 wt. % to 0.1 wt. % calcium; and aluminum; and casting the molten aluminum alloy to form an aluminum alloy product.

[0123] Aspect 47 is the method of any previous or subsequent aspect, further comprising homogenizing the aluminum alloy product to form a homogenized aluminum alloy product. [0124] Aspect 48 is the method of any previous or subsequent aspect, further comprising aging the aluminum alloy product.

[0125] Aspect 49 is the method of any previous or subsequent aspect, further comprising cold rolling the aluminum alloy product.

[0126] Aspect 50 is the method of any previous or subsequent aspect, further comprising hot rolling the aluminum alloy product.

[0127] Aspect 51 is the method of any previous or subsequent aspect, further comprising subjecting the aluminum alloy product to an elevated temperature.

[0128] Aspect 52 is the method of any previous or subsequent aspect, further comprising subjecting the aluminum alloy product to a corrosive environment.

[0129] Aspect 53 is the method of any previous or subsequent aspect, wherein a presence of the calcium in the aluminum alloy product increases an amount of time needed to induce stress corrosion cracks in the aluminum alloy product as referenced to a comparable aluminum alloy product comprising 3 wt. % to 10 wt. % magnesium or 6 wt. % to 12 wt. % zinc, magnesium, and copper combined and less than 0.001 wt. % calcium.

[0130] Aspect 54 is the method of any previous or subsequent aspect, further comprising subjecting the aluminum alloy to a marine environment.

[0131] Aspect 55 is the method of any previous, wherein the aluminum alloy product is the stress corrosion cracking-resistant aluminum alloy product of any previous aspect.

[0132] Aspect 56 is the stress corrosion cracking-resistant aluminum alloy product of any previous aspect prepared according to the method of any previous aspect.

[0133] All patents, publications and abstracts cited above are incorporated herein by reference in their entirety. The foregoing description of the embodiments, including illustrated embodiments, has been presented only for the purpose of illustration and description and is not intended to be exhaustive or limiting to the precise forms disclosed. Numerous modifications, adaptations, and uses thereof will be apparent to those skilled in the art.