KR20220092964A - Suppression of stress corrosion cracking in high magnesium alloys through calcium addition - Google Patents

Abstract

The stress corrosion cracking-resistant aluminum alloy product may include aluminum and a plurality of alloying elements. The plurality of alloying elements may include 3 wt% to 10 wt% magnesium and 0.001 wt% to 0.1 wt% at least one calcium. In some embodiments, the plurality of alloying elements may further comprise 0.001 wt% to 0.1 wt% strontium. In some embodiments, the plurality of alloying elements may further include silver.

Description

Suppression of stress corrosion cracking in high magnesium alloys through calcium addition

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit and priority of U.S. Provisional Application No. 62/949,286, filed December 17, 2019, which is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION The present disclosure relates generally to metallurgy, and more particularly to metal alloy products that resist stress corrosion cracking and methods of making metal alloy products.

High-strength and durable aluminum alloys are desirable for use in many different applications. Magnesium in solid solution is effective in strengthening aluminum alloys, and magnesium-containing aluminum alloys are relatively inert because magnesium oxide formed on the surface creates a barrier against corrosion. For example, 5xxx series aluminum alloys are generally considered relatively inert to seawater corrosion, making them particularly useful for offshore construction or offshore applications. 7xxx series aluminum alloys also exhibit good corrosion resistance in most environments. Nevertheless, the 5xxx series aluminum alloy containing a relatively high content of magnesium as an alloying element (eg 3% by weight or more) and the 7xxx series aluminum alloy containing little or no copper and zinc, magnesium and copper 7xxx series aluminum alloys containing relatively high amounts of the total (eg, greater than 6% by weight) may undergo stress corrosion cracking over time.

Stress corrosion cracking mainly occurs at grain boundaries where stress corrosion cracking can create intragranular pathways, especially in later stages where failure is mechanical rather than corrosive. The initiation of cracks requires deep depressions or depressions in the metal, such as etched grain boundaries. Crack growth usually starts slowly, but then deforms and becomes fast. Roughly, about 70% to about 90% of the time to failure is for nucleation of the crack. Cracks can also be triggered when gaps or dislocations build up.

Tensile (i.e. stress) is often a prerequisite for stress corrosion, and in bent samples cracks almost always initiate on the tensile side. The corrosion rate is usually proportional to the load, so the higher the load, the shorter the life. For forging products, the direction of the load relative to the crystal direction is important. The load applied in the short transverse direction may be less than one fifth of the load in the long transverse or longitudinal direction.

The wrinkled regions near the grain boundary and sub-boundary can play an important role in crack initiation. Crack initiation can be associated with the debarred region around the grain boundaries that can remain super saturated for the longest time with the greatest electronegativity with respect to matrix balance. Deposits at the crystal edges can promote cracking (like stamp holes), but electronegativity in the denuded region can be responsible for crack initiation.

Stress corrosion susceptibility may be related to oxide film ductility and crack growth rate. This stress corrosion susceptibility may be a result of the crack growth passivation rate: if the crack grows faster than passivation occurs, failure will follow. Stress-free corrosion tends to accelerate the ultimate stress corrosion cracking rate.

Structure can also be an important influence on stress corrosion cracking. A fine grain size reduces sensitivity, but a large number of sub-grain boundaries can produce a much greater improvement in resistance.

Stress corrosion cracking of magnesium-containing aluminum alloys results from nucleation at the recrystallized grain boundaries with increased temperature and/or time and Mg ₅ Al ₈ beta phase grains for 5xxx aluminum alloys or MgZn ₂ eta phase grains for 7xxx aluminum alloys. Conditions that promote the growth of certain magnesium-containing deposits, such as grains, may include conditions with magnesium-containing deposits on the edges of the recrystallized crystals, forming semi-continuous strings similar to strings of pearl necklaces. The relative electronegativity of the Mg ₅ Al ₈ beta phase or MgZn ₂ eta phase relative to the surrounding material in the crystal creates a corrosion event near the Mg ₅ Al ₈ beta phase or MgZn ₂ eta phase particles. Eventually, corrosion cells combined with either the Mg ₅ Al ₈ beta phase or the MgZn ₂ eta phase form weak spots in the microstructure, cracking or torn, which is used to guide the separation of how the holes formed between the stamps are used. It is similar to becoming

Depending on the sediment from the matrix, the sediment particles may or may not be continuous, or they may be separated or dispersed. However, nevertheless, cracks can propagate and damage the original state and eventually lead to failure of the alloy structure.

Embodiments and similar terms are intended to refer broadly to all subject matter of this disclosure and the claims below. Statements containing these terms are to be understood as not limiting the subject matter described herein or limiting the meaning or scope of the claims below. Embodiments of the present disclosure addressed herein are defined by the claims below and not by this summary. This Summary is a high-level overview of various aspects of the disclosure and introduces some of the concepts 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 separately to determine the scope of the claimed subject matter. The subject matter should be understood with reference to the entire specification of this disclosure, any or all drawings and the appropriate portion of each claim.

Described herein are stress corrosion cracking-resistant aluminum alloy products. The aluminum alloy products described herein advantageously exhibit good resistance to corrosion by including calcium, strontium, and/or silver in the alloy, which prevents crack formation and growth and fission while the aluminum alloy product is stressed in a corrosive environment. make it possible to resist Stress Corrosion Cracking Resistance and Classification of Metals such as Aluminum Alloys, ASTM G139-05 (2015), Standard Test for Determination of Stress-Corrosion Cracking Resistance of Heat-Treatable Aluminum Alloys Using the Breaking Loading Method, Hereby Incorporated by Reference 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), a standard test method for determining the susceptibility of 2XXX and 7XXX aluminum alloy products to stress-corrosion cracking, can be determined according to various standard test methods, such as ASTM International, West Conshohocken, PA, 2019.

Advantageously, the inclusion of calcium, strontium, and/or silver in the alloy provides the magnesium-containing aluminum alloy with a level of corrosion resistance beyond that achievable by including other alloying elements in the aluminum alloy. One embodiment stress corrosion cracking-resistant aluminum alloy product comprises a plurality of alloying elements comprising: 3 wt% to 10 wt% magnesium or 6 wt% to 15 wt% total of zinc, magnesium, and copper, and 0.001 wt% calcium % to 0.1% by weight; 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 weight percent to 0.1 weight percent silver. In embodiments, aluminum constitutes the remainder of the stress corrosion cracking-resistant aluminum alloy product (ie, the remainder of the alloy other than 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 depend on the particular aluminum alloy being used. Example aluminum alloys include 5xxx series aluminum alloys and 7xxx series aluminum alloys. Optionally, the plurality of alloying elements does not include zinc; This is that, in some cases, the alloy does not contain zinc or only contains zinc as a trace or unavoidable impurity. Optionally, the plurality of alloying elements further comprises zinc, such as in an amount of 0.1% to 15% by weight.

The stress corrosion cracking-resistant aluminum alloy products described herein may be prepared and processed according to any suitable method. In an embodiment, the stress corrosion cracking-resistant aluminum alloy product comprises from 3 wt% to 10 wt% aluminum, magnesium, 6 wt% to 15 wt% sum of zinc, magnesium, and copper, and 0.001 wt% to 0.01 wt% calcium It is prepared by casting an aluminum alloy containing. Optionally, the cast aluminum product is subjected to one or more hot rolling processes and/or one or more cold rolling processes. Other exemplary processes may include, but are not limited to, a homogenization process, a heat treatment process, an aging process, and similar processes.

In embodiments, the magnesium-containing aluminum alloy may contain magnesium-containing precipitates that may correspond to intermetallic particles. Example The magnesium-containing precipitate comprises Mg ₅ Al ₈ beta phase particles and MgZn ₂ eta phase particles. The presence of other magnesium-containing precipitates may depend on the particular alloy and process conditions. In some cases, magnesium-containing deposits can act as corrosion initiation sites, allowing corrosion to propagate and stress corrosion cracking to be a problem. By including calcium in the aluminum alloy, the presence or concentration 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, the stress corrosion cracking-resistant aluminum alloy product comprises less than 0.05% by weight of magnesium-containing precipitates, such as Mg ₅ Al ₈ beta phase particles or MgZn ₂ eta phase particles. In some cases, the magnesium-containing precipitate may also include zinc.

As mentioned above, the presence of magnesium-containing precipitates can be affected by the specific composition of the aluminum alloy and the processing conditions under which the aluminum alloy is made. In some embodiments, magnesium-containing precipitates in the stress corrosion cracking-resistant aluminum alloy product may be formed by exposure to a temperature between 50°C and 600°C. Optionally, a magnesium-containing precipitate is formed during the aging of the aluminum alloy product.

By including calcium, strontium, and/or silver in the alloy, calcium, strontium, and/or silver may be present in the magnesium-containing precipitate and/or magnesium-containing precipitate as compared to an alloy in which calcium, strontium and/or silver are present only in trace amounts The composition of the containing precipitate can be modified. The inclusion of calcium, strontium, and/or silver in the magnesium-containing precipitate may lower the likelihood of corrosion of the magnesium-containing precipitate as compared to a magnesium-containing precipitate that does not contain calcium, strontium and/or silver. Optionally, the presence of calcium, strontium, and/or silver in the aluminum alloy product comprises 3% to 10% by weight magnesium or 6% to 15% by weight sum of zinc, magnesium, copper and 0.001 calcium, strontium, and/or silver Reduces the amount of magnesium-containing deposits in stress corrosion cracking-resistant aluminum alloy products that are associated with comparable aluminum alloy products comprising less than % by weight and are subjected to the same process conditions.

When calcium, strontium and/or silver are present in an aluminum alloy, precipitates containing calcium, strontium and/or silver may form at grain boundaries. Optionally, the stress corrosion cracking-resistant aluminum alloy product may include one or more phases containing calcium, strontium and/or silver at grain boundaries of the aluminum alloy product. In some cases, one or more phases containing calcium, strontium, and/or silver may be produced by aging and/or exposure to elevated temperatures of 50°C to 600°C. Optionally, the one or more phases containing calcium, strontium, and/or silver comprise 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, one or more phases containing calcium, strontium, and/or silver may at least partially surround magnesium-containing precipitates located at grain boundaries, which will selectively limit or reduce the corrosive potential of the magnesium-containing precipitates. can

In another aspect, a method of making a stress corrosion cracking-resistant aluminum alloy product is described. An embodiment method of this aspect includes providing an aluminum alloy in a molten state as a molten aluminum alloy; and casting the molten aluminum alloy to form an aluminum alloy product, wherein the aluminum alloy comprises 3 wt% to 10 wt% magnesium or 6 wt% to 15 wt% total zinc, magnesium and copper, and 0.001 wt% calcium to 0.1% by weight. Other processing techniques may also be applied to the method of this aspect. For example, a method of this aspect may comprise homogenizing an aluminum alloy product to form a homogenized aluminum alloy product; aging the aluminum alloy product; cold rolling of the aluminum alloy product; hot rolling of the aluminum alloy product; exposing the aluminum alloy product to an elevated temperature; or exposing 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 highly corrosion or corrosion sensitive environments.

Advantageously, the presence of calcium, strontium, and/or silver in the aluminum alloy product is comprised of 3% to 10% by weight magnesium, 6% to 15% by weight sum of zinc, magnesium, copper, calcium, strotium, and/or silver It may increase the amount of time required to induce stress corrosion cracking in an aluminum alloy product relative to a comparable aluminum alloy product comprising less than 0.001 weight percent.

Other objects and advantages will become apparent from the detailed description of the following non-limiting examples.

The specification refers to the accompanying drawings in which the use of like reference numbers in different drawings is intended to illustrate similar or like elements.
1A schematically illustrates the formation of magnesium-containing precipitates at grain boundaries.
1B schematically illustrates corrosion occurring in the vicinity of magnesium-containing precipitate particles at grain boundaries.
2 provides an overview of an exemplary method of making an aluminum alloy product.

Described herein are aluminum alloy products and systems and methods for making and using aluminum alloy products. Aluminum alloy products described herein include products comprising magnesium-reinforced aluminum alloys with added calcium, strontium and/or silver. Advantageously, the added calcium, strontium and/or silver reduces the susceptibility of the aluminum alloy to stress corrosion cracking. By adding calcium, strontium and/or silver, Mg ₅ Al ₈ beta phase particles or MgZn ₂ eta phase particles at grain boundaries The growth of magnesium-containing deposits such as , may be altered and/or reduced compared to an aluminum alloy containing no or only trace amounts of calcium, strontium and/or silver. Alteration and/or reduced growth of beta or eta phase particles may inhibit stress corrosion cracking by reducing or limiting corrosion that may occur between the beta phase and surrounding crystals.

Definition and Description:

As used herein, the terms “invention”, “said invention”, “this invention” and “invention” are intended to refer broadly to all subject matter of this patent application and the claims that follow. It is to be understood that descriptions involving these terms do not limit the subject matter described herein or limit the meaning or scope of the following claims.

Reference is made in this description to alloys identified by AA numbers and other relevant designations such as “series” or “7xxx”. For an understanding of the numbering systems most commonly used to name and identify aluminum and its alloys, see "International Alloy Names and Chemical Composition Limitations for Forged Aluminum and Forged Aluminum Alloys" or "Cast and Ingot" published by the Aluminum Society. See "Registration of Aluminum Association Alloy Names and Chemical Composition Limitations for Aluminum Alloys in the Form of".

As used herein, a plate generally has a thickness greater than about 15 mm. For example, a plate refers to an aluminum product having a thickness 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. can do.

As used herein, a sheet (also referred to as a sheet plate) generally has a thickness of from about 4 mm to about 15 mm. For example, the sheath can 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.

As used herein, sheet generally refers to an aluminum product having a thickness of less than about 4 mm. For example, the sheet can 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 (eg, about 0.2 mm).

Reference may be made to alloy tempers or conditions in this application. For an understanding of the most commonly used alloy temper descriptions, see "American National Standard for Alloys and Temper Nomenclature System (ANSI) H35". F condition or temper refers to the manufactured aluminum alloy. O condition or temper refers to the aluminum alloy after annealing. Hxx conditions or tempers, also referred to herein as H tempers, refer to non-heat treatable aluminum alloys after cold rolling with or without heat treatment (eg, annealing). Suitable H tempers include HX1, HX2, HX3 HX4, HX5, HX6, HX7, HX8 or HX9 tempers. T1 condition or temper refers to an aluminum alloy that has been cooled from hot working and natural aging (eg, at room temperature). T2 condition or temper refers to an aluminum alloy that has been cooled from hot working, cold working and natural aging. T3 condition or temper refers to heat treated, cold worked and naturally aged aluminum alloy solutions. T4 condition or temper refers to an aluminum alloy solution that has been heat treated and aged naturally. T5 condition or temper refers to an aluminum alloy that has been artificially aged (at a high temperature) and cooled from hot working. T6 condition or temper refers to a heat treated and artificially aged aluminum alloy solution. T7 condition or temper refers to an aluminum alloy solution that has been heat treated and artificially overaged. T8x condition or temper refers to heat treated, cold worked and artificially aged aluminum alloy solutions. T9 condition or temper refers to heat treated, artificially aged and cold worked aluminum alloy solutions. The W condition or temper refers to an aluminum alloy after solution heat treatment.

As used herein, terms such as "cast metal product", "cast product", "cast aluminum alloy product", etc. are interchangeable and are either direct cooling casting (direct cooling co-casting) or semi-continuous casting, continuous casting. Refers to a product produced by (e.g., by use of a twin belt caster, twin roll caster, block caster, or any other continuous caster), electromagnetic casting, hot top casting, or any other casting method. do.

As used herein, “room temperature” means from about 15°C to about 30°C, such as about 15°C, about 16°C, about 17°C, about 18°C, 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” may include a temperature of about room temperature, a relative humidity of about 20% to about 100%, and an atmospheric pressure of about 975 mbar to about 1050 mbar. For example, relative humidity is 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 any position in between. For example, the atmospheric pressure is 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 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.

All ranges disclosed herein are to be understood to include any and all subranges subsumed therein. For example, a stated range "1 to 10" should be considered to include all subranges between (and inclusive of) the minimum value of 1 and the maximum value of 10. That is, all subranges begin with a minimum value of 1 or greater, eg, 1 to 6.1, and end with a maximum value of 10 or less, eg, 5.5 to 10. Unless otherwise specified, the expression "to" when referring to a compositional amount of an element means that the element is optional and that that particular element comprises a zero percent composition. Unless otherwise specified, all compositional percentages are by weight (wt %).

As used herein, the meanings of “a”, “an” and “the” include singular and plural references unless the context clearly dictates otherwise.

In the following examples, aluminum alloy products and their constituents are described in terms of elemental composition in weight percent (wt. %). In each alloy, the balance is aluminum, with the sum of all impurities up to 0.15% by weight.

Ancillary elements such as crystal refiners and deoxidizers, or other additives, may be present in embodiments of the present invention and may add other properties by themselves without departing or significantly altering the properties of the alloys described herein or of the alloys described herein. can

Due to the intrinsic properties of aluminum or leaching from contact with process equipment, small amounts of unavoidable impurities, including substances or elements, may be present in the alloy. Some impurities found in aluminum may include iron and silicon. As noted, the alloy may contain up to about 0.25 weight percent of any element other than alloying elements, minor elements, and unavoidable impurities.

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 metals and metal alloys treated and prepared accordingly. In some embodiments, the metal for use in the methods described herein comprises an aluminum alloy, eg, a 5xxx series aluminum alloy or a 7xxx series aluminum alloy. In some embodiments, materials for use in the methods described herein are aluminum, aluminum alloys, magnesium, magnesium-based materials, magnesium alloys, magnesium composites, titanium, titanium-based materials, titanium alloys, copper, copper-based materials, non-iron containing materials, non-metals, or combinations of materials including composites, sheets used in the composites, or any other suitable metal. Monolithic and non-monolithic such as roll bonded materials, clad alloys, cladding layers, composite materials, composite materials such as but not limited to carbon fiber-containing materials, or various other materials are useful in the methods described herein. do. In some embodiments, iron-containing aluminum alloys are useful in the methods described herein.

Non-limiting exemplary 5xxx series aluminum alloys for use as aluminum alloy products 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, AA545042, AA5043, AA495042, AA5043, AA5049, AA50 149 54 49 A AA5249, AA5 AA5050C, AA5150, AA5051, AA5051A, AA5151, AA5251, AA5251A, AA5351, AA5451, AA5052, AA5252, AA5352, AA5154, AA5154A, AA5154B, AA5154C, AA554, AA5154C, AA554, AA5354, 5654 AA5254, AA5354, AA54 AA54, AA5354, AA5056, AA5356, AA5356A, AA5456, AA5456A, AA5456B, AA5556, AA5556A, AA5556B, AA5556C, AA5257, AA5457, AA5557, AA5657, AA5058, AA5059, AA50283, AA5 AA5 AA50283, AA5 AA5 AA50 83 AA5 AA5180, 50 83 AA AA5283A, AA5283B, AA5383, AA5483, AA5086, AA5186, AA5087, AA5187, or AA5088.

Non-limiting exemplary 7xxx series aluminum alloys for use in the methods described herein are 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, AA7026, AA7029, AA70 22 71 AA70, AA70 , AA7033, AA7034, AA7036, AA7136, AA7037, AA7040, AA7140, AA7041, AA7049, AA7049A, AA7149,7204, AA7249, AA7349, AA7449, AA7050, AA7050A, 70 AA67150, AA70 AA7250, AA67150, AA70 AA7250 , AA7065, AA7068, AA7168, AA7175, AA7475, AA7076, AA7178, AA7278, AA7278A, AA7081, AA7181, AA7185, AA7090, AA7093, AA7095, or AA7099.

The following description will serve to further illustrate the present invention without constituting any limitation to the present invention, at the same time. On the contrary, it should be clearly understood that, after reading the description herein, various embodiments, modifications and equivalents thereof may be resorted to to those skilled in the art without departing from the spirit of the present invention.

High-strength and durable aluminum alloys are desirable for use in many different applications. Magnesium in solid solution is effective for strengthening aluminum alloys, and the alloy is also relatively inert because magnesium oxide formed on the surface creates a barrier against corrosion. However, nevertheless, aluminum alloys with magnesium, such as certain 5xxx aluminum alloys with a relatively high content of magnesium or certain 7xxx aluminum alloys with a relatively high sum of zinc, magnesium, and copper, may undergo stress corrosion cracking. have.

Stress corrosion cracking of magnesium-containing aluminum alloys involves conditions in which magnesium-containing particles are precipitated at the edges of recrystallized crystals with elevated temperature and/or time, which results in Mg ₅ Al ₈ at the recrystallized grain boundaries. Promotes nucleation and growth of beta phase particles or MgZn ₂ eta phase particles. 1A schematically illustrates the crystal structure of a magnesium-containing aluminum alloy, and shows the presence of Mg ₅ Al ₈ beta phase particles 105 at grain boundaries 110 . The relative electronegativity of the Mg ₅ Al ₈ beta phase to the surrounding material in the crystal can cause corrosion events in the vicinity of the Mg ₅ Al ₈ beta phase particles. Eventually, the corrosion cell combined with the Mg ₅ Al ₈ beta phase can form a weak region 115 in the microstructure, as schematically illustrated in the crystal structure shown in Fig. 1b, which will crack or tear under stress. can Similar corrosion behavior can be observed in aluminum alloy with discontinuous precipitation of MgZn ₂ eta phase along grain boundaries. Although Mg ₅ Al ₈ and MgZn ₂ are disclosed as exemplary magnesium-containing precipitates or magnesium-containing intermetallic compounds capable of forming particles at grain boundaries, other magnesium-containing phases or compounds such as Mg ₅ Al ₃ or other materials. It may also form at the grain boundaries of magnesium-reinforced aluminum alloys and/or make the alloy susceptible to stress corrosion cracking.

In the case of 5xxx aluminum alloy, when the magnesium content is 3% by weight or more, the precipitate of magnesium at grain boundaries, such as the formation of Mg ₅ Al ₈ beta phase grains at the grain boundaries, may be more pronounced, and the Mg ₅ Al ₈ beta phase is partially crystalline It is possible to selectively form semi-continuous strings of particles along the grain boundaries. However, depending on the processing and/or operating conditions, magnesium precipitates such as Mg ₅ Al ₈ beta phase formation may also occur when the magnesium content is less than 3% by weight. Depending on the magnesium content, the magnesium-containing precipitate may or may not be continuous and may separate or disperse. However, nevertheless, cracks can propagate and compromise strength, which in turn can lead to failure of the alloy product.

In the case of the 7xxx aluminum alloy, when the total content of zinc, magnesium, and copper is 6 wt% or more, the precipitate of magnesium at the grain boundaries, such as the formation of MgZn ₂ eta phase grains at the grain boundaries, may be more pronounced, and the MgZn ₂ eta phase is It is possible to selectively form semi-continuous strings of grains along some grain boundaries. However, depending on the processing and/or operating conditions, magnesium deposits such as MgZn ₂ eta phase formation may also occur when the total content of zinc, magnesium and copper is less than 6% by weight. Depending on the magnesium content, the magnesium-containing precipitate may or may not be continuous and may separate or disperse. However, nevertheless, cracks can propagate and compromise strength, which in turn can lead to failure of the alloy product.

Increased or elevated temperatures, such as between 50° C. and 600° C., can cause the growth of magnesium-containing precipitates. In some embodiments, elevated temperatures that may result in the growth of magnesium-containing precipitates such as Mg ₅ Al ₈ or MgZn ₂ may not be very high, and may be less than 200°C, for example less than 150°C, less than 100°C. , less than 50 °C, or less. Therefore, if heat treatment is performed on the magnesium-reinforced aluminum alloy, the heat treatment may be limited or careful control may be required to limit the formation of magnesium-containing precipitates. However, during subsequent processing of products made of various magnesium-reinforced aluminum alloys, such as welding, paint baking, etc., temperature rises are unavoidable and/or may occur. Therefore, magnesium-containing deposits are inevitably formed, and selective corrosion sites may be created, which may eventually lead to stress corrosion cracking.

In order to suppress stress corrosion cracking, calcium, strontium and/or silver are added to magnesium-reinforced aluminum alloy so that when calcium, strontium and/or silver are not added, corrosion that may occur at grain boundaries due to the presence of magnesium-containing precipitates can reduce By adding calcium, strontium and/or silver, the growth of the magnesium-containing precipitate can be altered. Without wishing to be bound by any particular theory, the inventors found that when magnesium-reinforced aluminum alloys are exposed to high temperatures, given the relatively low solubility in aluminum, calcium or strontium, or optionally silver, may precipitate with magnesium at grain boundaries. believe there is Magnesium precipitates, calcium precipitates, strontium precipitates, and/or silver precipitates may form one or more intermetallic compounds, which may or may not contain aluminum. Formation of intermetallic compounds containing magnesium, calcium, strontium, and/or silver may reduce the amount of magnesium, otherwise with Mg ₅ Al ₈ and/or MgZn ₂ The same magnesium-containing precipitate may form. The overall reduction of magnesium-containing deposits can lead to reduced corrosion at grain boundaries, thereby inhibiting stress corrosion cracking phenomena as compared to magnesium-containing aluminum alloys lacking or containing only trace amounts of calcium, strontium and/or silver or can be reduced Traces of calcium, strontium and/or silver may refer to amounts of each of calcium, strontium and/or silver which may be less than 0.001% by weight. Alternatively, precipitates or particles containing calcium, strontium and/or silver may be coated and/or positioned adjacent to magnesium-containing precipitates that may form at grain boundaries, such that the magnesium-containing precipitates and surrounding crystals are present. limit the corrosion reaction between The ductility of the oxide film at the crack tip can be modified constructively by adding calcium and/or strontium. Additionally, calcium and/or strontium may diversify or positively form a very stable calming layer in the crack tip region, reducing the overall growth rate of cracks originating in the denatured region of the crystal. In addition, calcium, strontium and/or silver remaining in the crystal may occur where magnesium-containing precipitates may be present by altering the electronegativity of the crystal itself and/or the relative electronegativity of the crystal as compared to the magnesium-containing precipitate. corrosion can be limited.

Depending on the application, the amount of calcium that can be added to the magnesium-reinforced aluminum alloy can range from 0.001% to 0.1% by weight. In some embodiments, the weight percent of calcium in the alloy is between 0.001% and 0.1%, between 0.005% and 0.1%, between 0.01% and 0.1%, between 0.015% and 0.1%, between 0.02% and 0.1%, between 0.025% and 0.1%, 0.03%. to 0.1%, 0.035% to 0.1%, 0.04% to 0.1%, 0.045% to 0.1%, 0.05% to 0.1%, 0.055% to 0.1%, 0.06% to 0.1%, 0.065% to 0.1%, 0.07% to 0.1 %, 0.075% to 0.1%, 0.08% to 0.1%, 0.085% to 0.1%, 0.09% to 0.1%, 0.095% to 0.1%, 0.001% to 0.095%, 0.005% to 0.095%, 0.01% to 0.095%, 0.015% to 0.095%, 0.02% to 0.095%, 0.025% to 0.095%, 0.03% to 0.095%, 0.035% to 0.095%, 0.04% to 0.095%, 0.045% to 0.095%, 0.05% to 0.095%, 0.055% to 0.095%, 0.06% to 0.095%, 0.065% to 0.095%, 0.07% to 0.095%, 0.075% to 0.095%, 0.08% to 0.095%, 0.085% to 0.095%, 0.09% to 0.095%, 0.001% to 0.09 %, 0.005% to 0.09%, 0.01% to 0.09%, 0.015% to 0.09%, 0.02% to 0.09%, 0.025% to 0.09%, 0.03% to 0.09%, 0.035% to 0.09%, 0.04% to 0.09%, 0.045% to 0.09%, 0.05% to 0.09%, 0.055% to 0.09%, 0.06% to 0.09%, 0.065% to 0.09%, 0.07% to 0.09%, 0.075% to 0.09%, 0.08% to 0.09%, 0.085% to 0.09%, 0.001% to 0.085%, 0.005% to 0.0 85%, 0.01% to 0.085%, 0.015% to 0.085%, 0.02% to 0.085%, 0.025% to 0.085%, 0.03% to 0.085%, 0.035% to 0.085%, 0.04% to 0.085%, 0.045% to 0.085% , 0.05% to 0.085%, 0.055% to 0.085%, 0.06% to 0.085%, 0.065% to 0.085%, 0.07% to 0.085%, 0.075% to 0.085%, 0.08% to 0.085%, 0.001% to 0.08%, 0.005 % to 0.08%, 0.01% to 0.08%, 0.015% to 0.08%, 0.02% to 0.08%, 0.025% to 0.08%, 0.03% to 0.08%, 0.035% to 0.08%, 0.04% to 0.08%, 0.045% to 0.08%, 0.05% to 0.08%, 0.055% to 0.08%, 0.06% to 0.08%, 0.065% to 0.08%, 0.07% to 0.08%, 0.075% to 0.08%, 0.001% to 0.075%, 0.005% to 0.075% , 0.01% to 0.075%, 0.015% to 0.075%, 0.02% to 0.075%, 0.025% to 0.075%, 0.03% to 0.075%, 0.035% to 0.075%, 0.04% to 0.075%, 0.045% to 0.075%, 0.05 % to 0.075%, 0.055% to 0.075%, 0.06% to 0.075%, 0.065% to 0.075%, 0.07% to 0.075%, 0.001% to 0.07%, 0.005% to 0.07%, 0.01% to 0.07%, 0.015% to 0.07%, 0.02% to 0.07%, 0.025% to 0.07%, 0.03% to 0.07%, 0.035% to 0.07%, 0.04% to 0.07%, 0.045% to 0.07%, 0.05% to 0.07%, 0.055% to 0.07% , 0.06% to 0.07%, 0.065% to 0.07, 0.001% to 0.065%, 0.005% to 0.065%, 0.01% to 0.065%, 0.015% to 0.065%, 0.02% to 0.065%, 0.025% to 0.065%, 0.03% to 0.065% , 0.035% to 0.065%, 0.04% to 0.065%, 0.045% to 0.065%, 0.05% to 0.065%, 0.055% to 0.065%, 0.06% to 0.065%, 0.001% to 0.06%, 0.005% to 0.06%, 0.01 % to 0.06%, 0.015% to 0.06%, 0.02% to 0.06%, 0.025% to 0.06%, 0.03% to 0.06%, 0.035% to 0.06%, 0.04% to 0.06%, 0.045% to 0.06%, 0.05% to 0.06%, 0.055% to 0.06%, 0.001% to 0.055%, 0.005% to 0.055%, 0.01% to 0.055%, 0.015% to 0.055%, 0.02% to 0.055%, 0.025% to 0.055%, 0.03% to 0.055% , 0.035% to 0.055%, 0.04% to 0.055%, 0.045% to 0.055%, 0.05% to 0.055%, 0.001% to 0.05%, 0.005% to 0.05%, 0.01% to 0.05%, 0.015% to 0.05%, 0.02 % to 0.05%, 0.025% to 0.05%, 0.03% to 0.05%, 0.035% to 0.05%, 0.04% to 0.05%, 0.045% to 0.05%, 0.001% to 0.045%, 0.005% to 0.045%, 0.01% to 0.045%, 0.015% to 0.045%, 0.02% to 0.045%, 0.025% to 0.045%, 0.03% to 0.045%, 0.035% to 0.045%, 0.04% to 0.045%, 0.001% to 0.04%, 0.005% to 0.0 4%, 0.01% to 0.04%, 0.015% to 0.04%, 0.02% to 0.04%, 0.025% to 0.04%, 0.03% to 0.04%, 0.035% to 0.04%, 0.001% to 0.035%, 0.005% to 0.035% , 0.01% to 0.035%, 0.015% to 0.035%, 0.02% to 0.035%, 0.025% to 0.035%, 0.03% to 0.035%, 0.001% to 0.03%, 0.005% to 0.03%, 0.01% to 0.03%, 0.015 % to 0.03%, 0.02% to 0.03%, 0.025% to 0.03%, 0.001% to 0.025%, 0.005% to 0.025%, 0.01% to 0.025%, 0.015% to 0.025%, 0.02% to 0.025%, 0.001% to 0.02%, 0.005% to 0.02%, 0.01% to 0.02%, 0.015% to 0.02%, 0.001% to 0.015%, 0.005% to 0.015%, 0.01% to 0.015%, 0.001% to 0.01%, 0.005% to 0.01% , or 0.001% to 0.005%.

Depending on the application, the amount of strontium that can be added to the magnesium-reinforced aluminum alloy can range from 0.001% to 0.1% by weight. In some embodiments, the weight percent of strontium in the alloy is between 0.001% and 0.1%, between 0.005% and 0.1%, between 0.01% and 0.1%, between 0.015% and 0.1%, between 0.02% and 0.1%, between 0.025% and 0.1%, 0.03%. to 0.1%, 0.035% to 0.1%, 0.04% to 0.1%, 0.045% to 0.1%, 0.05% to 0.1%, 0.055% to 0.1%, 0.06% to 0.1%, 0.065% to 0.1%, 0.07% to 0.1 %, 0.075% to 0.1%, 0.08% to 0.1%, 0.085% to 0.1%, 0.09% to 0.1%, 0.095% to 0.1%, 0.001% to 0.095%, 0.005% to 0.095%, 0.01% to 0.095%, 0.015% to 0.095%, 0.02% to 0.095%, 0.025% to 0.095%, 0.03% to 0.095%, 0.035% to 0.095%, 0.04% to 0.095%, 0.045% to 0.095%, 0.05% to 0.095%, 0.055% to 0.095%, 0.06% to 0.095%, 0.065% to 0.095%, 0.07% to 0.095%, 0.075% to 0.095%, 0.08% to 0.095%, 0.085% to 0.095%, 0.09% to 0.095%, 0.001% to 0.09 %, 0.005% to 0.09%, 0.01% to 0.09%, 0.015% to 0.09%, 0.02% to 0.09%, 0.025% to 0.09%, 0.03% to 0.09%, 0.035% to 0.09%, 0.04% to 0.09%, 0.045% to 0.09%, 0.05% to 0.09%, 0.055% to 0.09%, 0.06% to 0.09%, 0.065% to 0.09%, 0.07% to 0.09%, 0.075% to 0.09%, 0.08% to 0.09%, 0.085% to 0.09%, 0.001% to 0.085%, 0.005% to 0 .085%, 0.01% to 0.085%, 0.015% to 0.085%, 0.02% to 0.085%, 0.025% to 0.085%, 0.03% to 0.085%, 0.035% to 0.085%, 0.04% to 0.085%, 0.045% to 0.085 %, 0.05% to 0.085%, 0.055% to 0.085%, 0.06% to 0.085%, 0.065% to 0.085%, 0.07% to 0.085%, 0.075% to 0.085%, 0.08% to 0.085%, 0.001% to 0.08%, 0.005% to 0.08%, 0.01% to 0.08%, 0.015% to 0.08%, 0.02% to 0.08%, 0.025% to 0.08%, 0.03% to 0.08%, 0.035% to 0.08%, 0.04% to 0.08%, 0.045% to 0.08%, 0.05% to 0.08%, 0.055% to 0.08%, 0.06% to 0.08%, 0.065% to 0.08%, 0.07% to 0.08%, 0.075% to 0.08%, 0.001% to 0.075%, 0.005% to 0.075 %, 0.01% to 0.075%, 0.015% to 0.075%, 0.02% to 0.075%, 0.025% to 0.075%, 0.03% to 0.075%, 0.035% to 0.075%, 0.04% to 0.075%, 0.045% to 0.075%, 0.05% to 0.075%, 0.055% to 0.075%, 0.06% to 0.075%, 0.065% to 0.075%, 0.07% to 0.075%, 0.001% to 0.07%, 0.005% to 0.07%, 0.01% to 0.07%, 0.015% to 0.07%, 0.02% to 0.07%, 0.025% to 0.07%, 0.03% to 0.07%, 0.035% to 0.07%, 0.04% to 0.07%, 0.045% to 0.07%, 0.05% to 0.07%, 0.055% to 0.07 %, 0.06 % to 0.07%, 0.065% to 0.07, 0.001% to 0.065%, 0.005% to 0.065%, 0.01% to 0.065%, 0.015% to 0.065%, 0.02% to 0.065%, 0.025% to 0.065%, 0.03% to 0.065 %, 0.035% to 0.065%, 0.04% to 0.065%, 0.045% to 0.065%, 0.05% to 0.065%, 0.055% to 0.065%, 0.06% to 0.065%, 0.001% to 0.06%, 0.005% to 0.06%, 0.01% to 0.06%, 0.015% to 0.06%, 0.02% to 0.06%, 0.025% to 0.06%, 0.03% to 0.06%, 0.035% to 0.06%, 0.04% to 0.06%, 0.045% to 0.06%, 0.05% to 0.06%, 0.055% to 0.06%, 0.001% to 0.055%, 0.005% to 0.055%, 0.01% to 0.055%, 0.015% to 0.055%, 0.02% to 0.055%, 0.025% to 0.055%, 0.03% to 0.055 %, 0.035% to 0.055%, 0.04% to 0.055%, 0.045% to 0.055%, 0.05% to 0.055%, 0.001% to 0.05%, 0.005% to 0.05%, 0.01% to 0.05%, 0.015% to 0.05%, 0.02% to 0.05%, 0.025% to 0.05%, 0.03% to 0.05%, 0.035% to 0.05%, 0.04% to 0.05%, 0.045% to 0.05%, 0.001% to 0.045%, 0.005% to 0.045%, 0.01% to 0.045%, 0.015% to 0.045%, 0.02% to 0.045%, 0.025% to 0.045%, 0.03% to 0.045%, 0.035% to 0.045%, 0.04% to 0.045%, 0.001% to 0.04%, 0.005% to 0 .04%, 0.01% to 0.04%, 0.015% to 0.04%, 0.02% to 0.04%, 0.025% to 0.04%, 0.03% to 0.04%, 0.035% to 0.04%, 0.001% to 0.035%, 0.005% to 0.035 %, 0.01% to 0.035%, 0.015% to 0.035%, 0.02% to 0.035%, 0.025% to 0.035%, 0.03% to 0.035%, 0.001% to 0.03%, 0.005% to 0.03%, 0.01% to 0.03%, 0.015% to 0.03%, 0.02% to 0.03%, 0.025% to 0.03%, 0.001% to 0.025%, 0.005% to 0.025%, 0.01% to 0.025%, 0.015% to 0.025%, 0.02% to 0.025%, 0.001% to 0.02%, 0.005% to 0.02%, 0.01% to 0.02%, 0.015% to 0.02%, 0.001% to 0.015%, 0.005% to 0.015%, 0.01% to 0.015%, 0.001% to 0.01%, 0.005% to 0.01 %, or 0.001% to 0.005%.

Depending on the application, the amount of silver that can be added to the magnesium-reinforced aluminum alloy can range from 0.001% to 0.1% by weight. In some embodiments, the weight percent of silver in the alloy ranges from 0.001% to 0.1%, 0.005% to 0.1%, 0.01% to 0.1%, 0.015% to 0.1%, 0.02% to 0.1%, 0.025% to 0.1%, 0.03% to 0.1%, 0.035% to 0.1%, 0.04% to 0.1%, 0.045% to 0.1%, 0.05% to 0.1%, 0.055% to 0.1%, 0.06% to 0.1%, 0.065% to 0.1%, 0.07% to 0.1% , 0.075% to 0.1%, 0.08% to 0.1%, 0.085% to 0.1%, 0.09% to 0.1%, 0.095% to 0.1%, 0.001% to 0.095%, 0.005% to 0.095%, 0.01% to 0.095%, 0.015 % to 0.095%, 0.02% to 0.095%, 0.025% to 0.095%, 0.03% to 0.095%, 0.035% to 0.095%, 0.04% to 0.095%, 0.045% to 0.095%, 0.05% to 0.095%, 0.055% to 0.095%, 0.06% to 0.095%, 0.065% to 0.095%, 0.07% to 0.095%, 0.075% to 0.095%, 0.08% to 0.095%, 0.085% to 0.095%, 0.09% to 0.095%, 0.001% to 0.09% , 0.005% to 0.09%, 0.01% to 0.09%, 0.015% to 0.09%, 0.02% to 0.09%, 0.025% to 0.09%, 0.03% to 0.09%, 0.035% to 0.09%, 0.04% to 0.09%, 0.045 % to 0.09%, 0.05% to 0.09%, 0.055% to 0.09%, 0.06% to 0.09%, 0.065% to 0.09%, 0.07% to 0.09%, 0.075% to 0.09%, 0.08% to 0.09%, 0.085% to 0.09%, 0.001% to 0.085%, 0.005% to 0.08 5%, 0.01% to 0.085%, 0.015% to 0.085%, 0.02% to 0.085%, 0.025% to 0.085%, 0.03% to 0.085%, 0.035% to 0.085%, 0.04% to 0.085%, 0.045% to 0.085% , 0.05% to 0.085%, 0.055% to 0.085%, 0.06% to 0.085%, 0.065% to 0.085%, 0.07% to 0.085%, 0.075% to 0.085%, 0.08% to 0.085%, 0.001% to 0.08%, 0.005 % to 0.08%, 0.01% to 0.08%, 0.015% to 0.08%, 0.02% to 0.08%, 0.025% to 0.08%, 0.03% to 0.08%, 0.035% to 0.08%, 0.04% to 0.08%, 0.045% to 0.08%, 0.05% to 0.08%, 0.055% to 0.08%, 0.06% to 0.08%, 0.065% to 0.08%, 0.07% to 0.08%, 0.075% to 0.08%, 0.001% to 0.075%, 0.005% to 0.075% , 0.01% to 0.075%, 0.015% to 0.075%, 0.02% to 0.075%, 0.025% to 0.075%, 0.03% to 0.075%, 0.035% to 0.075%, 0.04% to 0.075%, 0.045% to 0.075%, 0.05 % to 0.075%, 0.055% to 0.075%, 0.06% to 0.075%, 0.065% to 0.075%, 0.07% to 0.075%, 0.001% to 0.07%, 0.005% to 0.07%, 0.01% to 0.07%, 0.015% to 0.07%, 0.02% to 0.07%, 0.025% to 0.07%, 0.03% to 0.07%, 0.035% to 0.07%, 0.04% to 0.07%, 0.045% to 0.07%, 0.05% to 0.07%, 0.055% to 0.07% , within 0.06% 0.07%, 0.065% to 0.07, 0.001% to 0.065%, 0.005% to 0.065%, 0.01% to 0.065%, 0.015% to 0.065%, 0.02% to 0.065%, 0.025% to 0.065%, 0.03% to 0.065% , 0.035% to 0.065%, 0.04% to 0.065%, 0.045% to 0.065%, 0.05% to 0.065%, 0.055% to 0.065%, 0.06% to 0.065%, 0.001% to 0.06%, 0.005% to 0.06%, 0.01 % to 0.06%, 0.015% to 0.06%, 0.02% to 0.06%, 0.025% to 0.06%, 0.03% to 0.06%, 0.035% to 0.06%, 0.04% to 0.06%, 0.045% to 0.06%, 0.05% to 0.06%, 0.055% to 0.06%, 0.001% to 0.055%, 0.005% to 0.055%, 0.01% to 0.055%, 0.015% to 0.055%, 0.02% to 0.055%, 0.025% to 0.055%, 0.03% to 0.055% , 0.035% to 0.055%, 0.04% to 0.055%, 0.045% to 0.055%, 0.05% to 0.055%, 0.001% to 0.05%, 0.005% to 0.05%, 0.01% to 0.05%, 0.015% to 0.05%, 0.02 % to 0.05%, 0.025% to 0.05%, 0.03% to 0.05%, 0.035% to 0.05%, 0.04% to 0.05%, 0.045% to 0.05%, 0.001% to 0.045%, 0.005% to 0.045%, 0.01% to 0.045%, 0.015% to 0.045%, 0.02% to 0.045%, 0.025% to 0.045%, 0.03% to 0.045%, 0.035% to 0.045%, 0.04% to 0.045%, 0.001% to 0.04%, 0.005% to 0.04 %, 0.01% to 0.04%, 0.015% to 0.04%, 0.02% to 0.04%, 0.025% to 0.04%, 0.03% to 0.04%, 0.035% to 0.04%, 0.001% to 0.035%, 0.005% to 0.035%, 0.01% to 0.035%, 0.015% to 0.035%, 0.02% to 0.035%, 0.025% to 0.035%, 0.03% to 0.035%, 0.001% to 0.03%, 0.005% to 0.03%, 0.01% to 0.03%, 0.015% to 0.03%, 0.02% to 0.03%, 0.025% to 0.03%, 0.001% to 0.025%, 0.005% to 0.025%, 0.01% to 0.025%, 0.015% to 0.025%, 0.02% to 0.025%, 0.001% to 0.02 %, 0.005% to 0.02%, 0.01% to 0.02%, 0.015% to 0.02%, 0.001% to 0.015%, 0.005% to 0.015%, 0.01% to 0.015%, 0.001% to 0.01%, 0.005% to 0.01%, or 0.001% to 0.005%.

For 5xxx aluminum alloys, the amount of magnesium the alloy may contain may range from 3% to 10% by weight. In some embodiments, the weight percent of magnesium is between 3% and 10%, between 3.5% and 10%, between 4% and 10%, between 4.5% and 10%, between 5% and 10%, between 5.5% and 10%, between 6% and 10%. %, 6.5% to 10%, 7% to 10%, 7.5% to 10%, 8% to 10%, 8.5% to 10%, 9% to 10%, 9.5% to 10%, 3% to 9.5%, 3.5% to 9.5%, 4% to 9.5%, 4.5% to 9.5%, 5% to 9.5%, 5.5% to 9.5%, 6% to 9.5%, 6.5% to 9.5%, 7% to 9.5%, 7.5% to 9.5%, 8% to 9.5%, 8.5% to 9.5%, 9% to 9.5%, 3% to 9%, 3.5% to 9%, 4% to 9%, 4.5% to 9%, 5% to 9 %, 5.5% to 9%, 6% to 9%, 6.5% to 9%, 7% to 9%, 7.5% to 9%, 8% to 9%, 8.5% to 9%, 3% to 8.5%, 3.5% to 8.5%, 4% to 8.5%, 4.5% to 8.5%, 5% to 8.5%, 5.5% to 8.5%, 6% to 8.5%, 6.5% to 8.5%, 7% to 8.5%, 7.5% to 8.5%, 8% to 8.5%, 3% to 8%, 3.5% to 8%, 4% to 8%, 4.5% to 8%, 5% to 8%, 5.5% to 8%, 6% to 8 %, 6.5% to 8%, 7% to 8%, 7.5% to 8%, 3% to 7.5%, 3.5% to 7.5%, 4% to 7.5%, 4.5% to 7.5%, 5% to 7.5%, 5.5% to 7.5%, 6% to 7.5%, 6.5% to 7.5%, 7% to 7.5%, 3% to 7%, 3.5% to 7%, 4% to 7%, 4.5% to 7%, 5% to 7%, 5.5% to 7%, 6% to 7%, 6.5% to 7%, 3% to 6.5%, 3.5% to 6.5%, 4% to 6.5%, 4.5% to 6.5%, 5% to 6.5%, 5.5% to 6.5%, 6% to 6.5%, 3% to 6%, 3.5% to 6%, 4% to 6%, 4.5% to 6%, 5% to 6%, 5.5% to 6%, 3% to 5.5%, 3.5% to 5.5%, 4% to 5.5%, 4.5% to 5.5%, 5% to 5.5%, 3% to 5%, 3.5% to 5%, 4% to 5 %, 4.5% to 5%, 3% to 4.5%, 3.5% to 4.5%, 4% to 4.5%, 3% to 4%, 3.5% to 4%, or 3% to 3.5%.

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

As discussed above, when a magnesium-reinforced aluminum alloy contains at least 3 wt% magnesium for a 5xxx aluminum alloy, or at least 6 wt% of the sum of zinc, magnesium and copper for a 7xxx aluminum alloy, the alloy is subjected to stress corrosion It can be more prone to cracking. Nevertheless, magnesium-reinforced aluminum alloys containing less than 3% by weight magnesium or less than 6% by weight of zinc, magnesium, and copper in total may also be susceptible to stress corrosion cracking. Accordingly, calcium, strontium, and/or silver may also be added to magnesium-reinforced aluminum alloys having less than 3 wt. % magnesium or less than 6 wt. Suppresses stress corrosion cracking when exposed to corrosive environments. For example, the amount of magnesium a 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 is 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 about 1%, or in the range of 1.5% to 3%. Optionally, the amount of magnesium is 1.5% to 3%, 1.6% to 3%, 1.7% to 3%, 1.8% to 3%, 1.9% to 3%, 2% to 3%, 2.1% to 3%, 2.2% to 3%, 2.3% to 3%, 2.4% to 3%, 2.5% to 3%, 2.6% to 3%, 2.7% to 3%, 2.8% to 3%, 2.9% to 3%, 1.5% to 2.9 %, 1.6% to 2.9%, 1.7% to 2.9%, 1.8% to 2.9%, 1.9% to 2.9%, 2% to 2.9%, 2.1% to 2.9%, 2.2% to 2.9%, 2.3% to 2.9%, 2.4% to 2.9%, 2.5% to 2.9%, 2.6% to 2.9%, 2.7% to 2.9%, 2.8% to 2.9%, 1.5% to 2.8%, 1.6% to 2.8%, 1.7% to 2.8%, 1.8% to 2.8%, 1.9% to 2.8%, 2% to 2.8%, 2.1% to 2.8%, 2.2% to 2.8%, 2.3% to 2.8%, 2.4% to 2.8%, 2.5% to 2.8%, 2.6% to 2.8 %, 2.7% to 2.8%, 1.5% to 2.7%, 1.6% to 2.7%, 1.7% to 2.7%, 1.8% to 2.7%, 1.9% to 2.7%, 2% to 2.7%, 2.1% to 2.7%, 2.2% to 2.7%, 2.3% to 2.7%, 2.4% to 2.7%, 2.5% to 2.7%, 2.6% to 2.7%, 1.5% to 2.6%, 1.6% to 2.6%, 1.7% to 2.6%, 1.8% to 2.6%, 1.9% to 2.6%, 2% to 2.6%, 2.1% to 2.6%, 2.2% to 2.6%, 2.3% to 2.6%, 2.4% to 2.6%, 2.5% to 2.6%, 1.5% to 2.5 %, 1.6% to 2.5%, 1.7% to 2.5%, 1.8% to 2.5%, 1.9% to 2.5%, 2% to 2.5%, 2.1% to 2.5%, 2.2% to 2.5%, 2.3% to 2.5%, 2.4% to 2.5%, 1.5% to 2.4%, 1.6% to 2.4%, 1.7% to 2.4%, 1.8% to 2.4%, 1.9% to 2.4%, 2% to 2.4%, 2.1% to 2.4 %, 2.2% to 2.4%, 2.3% to 2.4%, 1.5% to 2.3%, 1.6% to 2.3%, 1.7% to 2.3%, 1.8% to 2.3%, 1.9% to 2.3%, 2% to 2.3%, 2.1% to 2.3%, 2.2% to 2.3%, 1.5% to 2.2%, 1.6% to 2.2%, 1.7% to 2.2%, 1.8% to 2.2%, 1.9% to 2.2%, 2% to 2.2%, 2.1% to 2.2%, 1.5% to 2.1%, 1.6% to 2.1%, 1.7% to 2.1%, 1.8% to 2.1%, 1.9% to 2.1%, 2% to 2.1%, 1.5% to 2%, 1.6% to 2 %, 1.7% to 2%, 1.8% to 2%, 1.9% to 2%, 1.5% to 1.9%, 1.6% to 1.9%, 1.7% to 1.9%, 1.8% to 1.9%, 1.5% to 1.8%, 1.6% to 1.8%, 1.7% to 1.8%, 1.5% to 1.7%, 1.6% to 1.7%, or 1.5% to 1.6%. For example, the sum 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 weight percent of the sum of zinc, magnesium and copper that the 7xxx aluminum alloy may contain is 0.5% to 6%, 0.5% to 5.5%, 0.5% to 5%, 0.5% to 4.5%, 0.5% to 4%, 0.5% to 3.5%, 0.5% to 3%, 0.5% to 2.5%, 0.5% to 2%, 0.5% to 1.5%, 0.5% to 1%, 1% to 6%, 1% to 5.5 %, 1% to 5%, 1% to 4.5%, 1% to 4%, 1% to 3.5%, 1% to 3%, 1% to 2.5%, 1% to 2%, 1% to 1.5%, 1.5% to 6%, 1.5% to 5.5%, 1.5% to 5%, 1.5% to 4.5%, 1.5% to 4%, 1.5% to 3.5%, 1.5% to 3%, 1.5% to 2.5%, 1.5% to 2%, 2% to 6%, 2% to 5.5%, 2% to 5%, 2% to 4.5%, 2% to 4%, 2% to 3.5%, 2% to 3%, 2% to 2.5 %, 2.5% to 6%, 2.5% to 5.5%, 2.5% to 5%, 2.5% to 4.5%, 2.5% to 4%, 2.5% to 3.5%, 2.5% to 3%, 3% to 6%, 3% to 5.5%, 3% to 5%, 3% to 4.5%, 3% to 4%, 3% to 3.5%, 3.5% to 6%, 3.5% to 5.5%, 3.5% to 5%, 3.5% to 4.5%, 3.5% to 4%, 4% to 6%, 4% to 5.5%, 4% to 5%, 4% to 4.5%, 4.5% to 6%, 4.5% to 5.5%, 4.5% to 5 %, 5% to 6%, 5% to 5.5%, or 5.5% to 6%.

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

Depending on the amount of magnesium in the 5xxx aluminum alloy or the total amount of zinc, magnesium, and copper in the 7xxx aluminum alloy, the amount of strontium that can be added to effectively suppress stress corrosion cracking may vary. For example, the 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, the ratio of the amount of strontium in the alloy to the amount of magnesium in the alloy is from 0.0001 to 1, 0.0001 to 0.1, 0.0001 to 0.01, 0.0001 to 0.001, 0.001 to 1, 0.001 to 0.1, 0.001 to 0.01, 0.01 to 1, 0.01 to 0.1, or in the range of 0.1 to 1. The ratio of the amount of strontium to the total amount of zinc, magnesium and copper in the 7xxx alloy may range from about 0.0001 to about 1. Optionally the ratio of the amount of strontium in the alloy to the total amount of zinc, magnesium and copper in the metal is 0.0001 to 1, 0.0001 to 0.1, 0.0001 to 0.01, 0.0001 to 0.001, 0.001 to 1, 0.001 to 0.1, 0.001 to 0.01, 0.01 to 1, 0.01 to 0.1, or 0.1 to 1.

Depending on the amount of magnesium in the 5xxx aluminum alloy or the total amount of zinc, magnesium, and copper in the 7xxx aluminum alloy, the amount of silver that can be added to effectively suppress stress corrosion cracking may vary. For example, the 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, the ratio of the amount of silver in the alloy to the amount of magnesium in the alloy is 0.0001 to 1, 0.0001 to 0.1, 0.0001 to 0.01, 0.0001 to 0.001, 0.001 to 1, 0.001 to 0.1, 0.001 to 0.01, 0.01 to 1, 0.01 to 0.1 , or may be in the range of 0.1 to 1. The ratio of the amount of silver to the total amount of zinc, magnesium and copper in the 7xxx alloy may range from about 0.0001 to about 1. Optionally, the ratio of the amount of silver in the alloy to the total amount of zinc, magnesium and copper in the alloy is from 0.0001 to 1, 0.0001 to 0.1, 0.0001 to 0.01, 0.0001 to 0.001, 0.001 to 1, 0.001 to 0.1, 0.001 to 0.01, 0.01 to 1, 0.01 to 0.1, or 0.1 to 1.

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

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

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

As mentioned above, the series of aluminum alloys that may be more susceptible to stress corrosion cracking compared to other aluminum alloys may include the 5xxx series and 7xxx series.

2 provides an overview of an exemplary method of making an aluminum alloy product. The method of FIG. 2 begins at step 205 in which 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 shows a schematic illustration of a direct cold casting process, the aluminum alloys described herein may be cast using a continuous casting process. A continuous casting system may include a pair of moving opposing casting surfaces (eg, moving opposing belts, rolls, blocks), a casting cavity between the pair of moving opposing casting surfaces, and a molten metal injector. The molten metal injector may have an open end through which molten metal may exit the molten metal injector and be injected into the casting cavity.

Molten aluminum alloy 206 may include molten aluminum, magnesium and calcium and optionally strontium or silver. In some implementations, the molten aluminum alloy 206 may further include zinc. The amounts of magnesium, calcium, and zinc (in weight percent) may each be any of the various amounts discussed above or subranges thereof. Depending on the application, the molten aluminum alloy 206 may further include one or more other alloying elements, such as manganese, zirconium, scandium, silicon, iron, copper, chromium, titanium, and the like.

The cast aluminum alloy product 207 may then be processed by any suitable means. As discussed above, heat treatment of conventional magnesium-reinforced aluminum alloys to limit the formation of magnesium-containing deposits can be avoided or, if performed, require close control, which can eventually lead to stress corrosion cracking. . Accordingly, conventional magnesium-reinforced aluminum alloys are generally work hardened and in H condition or temper. In contrast, when calcium is added to a magnesium-reinforced aluminum alloy as disclosed herein, as discussed above, the alloy may be significantly less susceptible to stress corrosion cracking. Accordingly, the magnesium-reinforced aluminum alloy comprising calcium as an alloying element may be work hardened and/or heat treated. The resulting alloy may be in H temper or T temper as appropriate. Suitable H tempers are H1X, H2X, H3X, H4X, or H111, H112, H115, H116, H12, H14, H16, H18, H19, H24, H26, H28, H32, H321, H323, H34, H343, H36, H38 , , and the like. Suitable T tempers are T1, 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, and the like. Exemplary processing steps may include homogenization, hot rolling, cold rolling, annealing, solution heat treatment, pre-aging or the like.

Some exemplary process steps are shown in FIG. 2 . In 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 to a temperature in the range of about 400°C to about 500°C. For example, product 207 can be at 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 It can be heated to a temperature of about 500 °C. The product 207 may then be allowed to soak (ie, remain at the indicated temperature) for a period of time. In some embodiments, the total time for the homogenization steps, including heating and soaking phases, may be up to 24 hours. For example, product 207 may be heated and soaked to 500° C. for a total time of up to 18 hours for the homogenization step. Optionally, product 207 may be heated and soaked below 490° C. for a total time of greater than 18 hours for the homogenization step. In some cases, the homogenization step comprises several processes. In some non-limiting embodiments, the homogenizing step comprises 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, 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.

Subsequent to the homogenizing step, in step 215, the homogenized aluminum alloy product 211 is passed through one or more rolling passes to form a rolled aluminum alloy product 212, which may be an aluminum alloy plate, aluminum shed, or coiled after rolling. It can correspond to an aluminum alloy product such as an aluminum sheet.

If a hot rolling step is performed, prior to hot rolling, the homogenized product 211 may be allowed to cool to a temperature such as between 300°C and 450°C. For example, the homogenized product 211 may be allowed to cool to a temperature between 325°C and 425°C or between 350°C and 400°C. In some embodiments, the cast product can be a continuous cast product that can be allowed to cool to a temperature of 300°C to 450°C. The product may then be hot rolled at a suitable temperature, such as between 300° C. and 450° C., such that a hot rolled plate, a hot rolled sheet or between 3 mm and 200 mm (e.g., 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8mm, 9mm, 10mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm, 55mm, 60mm, 65mm, 70mm, 75mm, 80mm, 85mm, 90mm, 95mm, 100mm, 110mm, 120mm, 130mm, 140mm, 150mm, 160mm, 170mm, 180mm, 190mm, 200mm or any position in between) to form a hot rolled intermediate product such as a hot rolled sheet having a gauge. The temperature and other operating parameters during hot rolling can be controlled so that the temperature of the hot rolling intermediate product when exiting from the hot rolling mill is 470°C or less, 450°C or less, 440°C or less, or 430°C or less.

The hot rolled product may then be cold rolled into a cold rolled product having a gauge between about 0.5 mm and 10 mm, for example between about 0.7 mm and 6.5 mm. Optionally, the cold rolled sheet is 0.5mm, 1.0mm, 1.5mm, 2.0mm, 2.5mm, 3.0mm, 3.5mm, 4.0mm, 4.5mm, 5.0mm, 5.5mm, 6.0mm, 6.5mm, 7.0mm, 7.5 It can have gauges of mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm or 10.0 mm. Cold rolling is performed so that the final gauge thickness is reduced in gauge by up to 85% compared to the annual rolled product (e.g. up to 10%, up to 20%, up to 30%, up to 40%, up to 50%, up to 60%, Final gauge thicknesses exhibiting up to 70%, up to 80% or up to 85% reduction) can be obtained. In some embodiments, the interannealing step may be performed during the cold rolling step. The interannealing step may be performed at about 300°C to about 450°C (eg, 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. °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 includes multiple processes. In some non-limiting embodiments, the interannealing step comprises 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 may be heated to about 410° C. for about 1 hour and then heated to about 330° C. for about 2 hours.

In some embodiments, the rolled product may be subjected to a solution heat treatment step. The solution heat treatment step can be any treatment to the sheet that results in solutionization of the soluble particles. Magnesium-reinforced aluminum alloys with added calcium may be less susceptible to stress corrosion cracking, so solution heat treatment may be omitted. When solution heat treatment is performed, the rolled product may be heated to a peak metal temperature (PMT) of up to 590° C. (eg, 400° C. to 590° C.) and immersed at that temperature for a period of time. For example, the rolled product may be immersed at 480° C. for a period of up to 30 minutes (eg, 0 seconds, 60 seconds, 75 seconds, 90 seconds, 5 minutes, 10 minutes, 20 minutes, 25 minutes, or 30 minutes). can be After heating and immersion, the product can be rapidly cooled to a temperature between 500 and 200° C. at a rate greater than 200° C./s. In one embodiment, the product may undergo a quench rate of greater than 200°C/sec at a temperature between 450°C and 200°C. Optionally, the cooling rate may be faster in other cases.

After quenching, the heat treated product may optionally be subjected to a pre-aging treatment by reheating the product prior to coiling. The pre-aging treatment may be performed at a temperature of about 70° C. to about 125° C. for a period of up to 6 hours. For example, the pre-aging treatment may be 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 at a temperature of about 125°C. In some embodiments, the pre-aging treatment may 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 may be accomplished by passing the plate, sheet or sheet through a heating device, such as a device that emits radiant heat, convective heat, induction heat, infrared heat or the like.

The cast products described herein can be used to make products in the form of plates or other suitable products. For example, a plate comprising a product as described herein may be prepared by processing the ingot in a homogenization step or by casting the product in a continuous casting machine followed by a hot rolling step. In the hot rolling step, the cast product may be hot rolled to a gauge 200 mm thick or less (eg, about 10 mm to about 200 mm). For example, the cast product may be 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. can be hot rolled.

As discussed above, added calcium may alter or limit the formation of magnesium-containing precipitates at grain boundaries when the magnesium-reinforced aluminum alloy may be exposed to elevated temperatures. Thus, in addition to the heat treatments discussed above, the magnesium-reinforced aluminum alloys described herein may be further exposed to elevated temperatures such as welding, paint baking, etc. without increasing the risk 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 is 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 It may range from 50°C to 100°C.

Considering the inhibitory effect of added calcium on stress corrosion cracking, magnesium-reinforced aluminum alloy can be used in corrosive environments such as marine applications, automotive reinforcement/chassis applications or such applications while reducing susceptibility to stress corrosion cracking.

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

Exemplary aspect

As used below, any reference to a series of embodiments is to be understood as reference to each separate embodiment (eg, "aspects 1-4" means "aspects 1, 2, 3 or 4"). should be understood as ".

Aspect 1 is a stress corrosion cracking-resistant aluminum alloy product comprising a plurality of alloying elements comprising: 3 wt % to 10 wt % magnesium or 6 wt % to 15 wt % zinc, magnesium and copper sum; 0.001% to 0.1% calcium by weight; and a stress corrosion cracking-resistant aluminum alloy product comprising aluminum.

Aspect 2 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, wherein the aluminum constitutes the remainder of the stress corrosion cracking-resistant aluminum alloy product.

Aspect 3 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, wherein the plurality of alloying elements further comprises from 0.001 weight percent to 0.1 weight percent strontium.

Aspect 4 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, wherein the plurality of alloying elements further comprises from 0.001 weight percent to 0.1 weight percent silver.

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

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

Aspect 7 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, wherein the cast aluminum product has been produced through one or more hot rolling processes.

Aspect 8 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, wherein the cast aluminum product has been produced through one or more cold rolling processes.

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

Aspect 10 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, wherein the plurality of alloying elements do not include zinc.

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

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

Aspect 13 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, wherein the plurality of alloying elements comprises 0.1 weight percent to 15 weight percent zinc.

Aspect 14 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, comprising a magnesium-containing precipitate.

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

Aspect 16 is any previous or subsequent aspect, wherein the magnesium-containing precipitate comprises Mg ₅ Al ₈ beta phase particles, and the stress corrosion cracking-resistant aluminum alloy product comprises less than 0.05% by weight of Mg ₅ Al ₈ beta phase particles. It is a stress corrosion crack-resistant aluminum alloy product.

Aspect 17 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, wherein the magnesium-containing precipitate comprises Mg and/or Zn.

Aspect 18 is the stress corrosion cracking of any preceding or subsequent aspect, wherein the magnesium-containing precipitate comprises MgZn ₂ eta phase particles, and the stress corrosion cracking-resistant aluminum alloy product comprises less than 10% by weight of the MgZn ₂ eta phase particles. - Resistant aluminum alloy product.

Aspect 19 is the stress corrosion cracking of any preceding or subsequent aspect, wherein the magnesium-containing precipitate comprises MgZn ₂ eta phase particles, and the stress corrosion cracking-resistant aluminum alloy product comprises less than 5 weight percent of the MgZn ₂ eta phase particles. - Resistant aluminum alloy product.

Aspect 20 is the stress corrosion cracking of any preceding or subsequent aspect, wherein the magnesium-containing precipitate comprises MgZn ₂ eta phase particles, and the stress corrosion cracking-resistant aluminum alloy product comprises less than 1% by weight of the MgZn ₂ eta phase particles. - Resistant aluminum alloy product.

Aspect 21 is the stress corrosion cracking of any preceding or subsequent aspect, wherein the magnesium-containing precipitate comprises MgZn ₂ eta phase particles, and the stress corrosion cracking-resistant aluminum alloy product comprises less than 0.1 weight percent of the MgZn ₂ eta phase particles. - Resistant aluminum alloy product.

Aspect 22 is the stress corrosion cracking of any preceding or subsequent aspect, wherein the magnesium-containing precipitate comprises MgZn ₂ eta phase particles, and the stress corrosion cracking-resistant aluminum alloy product comprises less than 0.05 weight percent of the MgZn ₂ eta phase particles. - Resistant aluminum alloy product.

Aspect 23 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, wherein the magnesium-containing precipitate was formed through exposure to a temperature between 50° C. and 600° C.

Aspect 24 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, wherein a magnesium-containing precipitate is formed during aging.

Aspect 25 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, wherein the magnesium-containing precipitate comprises calcium.

Aspect 26 provides an aspect 26 wherein the presence of calcium in the aluminum alloy product comprises a comparable aluminum alloy product comprising from 3 wt% to 10 wt% magnesium or from 6 wt% to 12 wt% sum of zinc, magnesium, and copper and less than 0.001 wt% calcium; A related, stress corrosion cracking-resistant aluminum alloy product of any previous or subsequent aspect that reduces the amount of magnesium-containing deposits in a stress corrosion cracking-resistant aluminum alloy product subjected to the same process conditions.

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

Aspect 28 is the stress corrosion cracking-resistant aluminum alloy of any preceding or subsequent aspect, wherein the at least one phase is produced by exposure to an elevated temperature of 50° C. to 600° C.

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

Aspect 30 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, wherein the at least one phase comprises calcium metal.

Aspect 31 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, wherein at least one phase comprises strontium metal.

Aspect 32 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, comprising one or more different silver metals.

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

Aspect 34 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, wherein one phase of the one or more phases comprises strontium and magnesium.

Aspect 35 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, wherein the one or more phases include silver and magnesium in one or more phases.

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

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

Aspect 38 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, wherein the one or more phases comprises silver and aluminum in one or more phases.

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

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

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

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

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

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

Aspect 45 is the stress corrosion cracking-resistant aluminum alloy product of any preceding or subsequent aspect, wherein one phase of the one or more phases at least partially encloses a magnesium-containing precipitate located at grain boundaries.

Aspect 46 is a method of making a stress corrosion cracking-resistant aluminum alloy product, the method comprising: providing the aluminum alloy in a molten state as a molten aluminum alloy; and casting the molten aluminum alloy to produce an aluminum alloy product, wherein the aluminum alloy comprises 3 wt% to 10 wt% magnesium or 6 wt% to 12 wt% total of zinc, magnesium, and copper; 0.001 wt% to 0.1 wt% calcium; and aluminum.

Aspect 47 is the method of any preceding or subsequent aspect, further comprising homogenizing the aluminum alloy product to form a homogenized aluminum alloy product.

Aspect 48 is the method of any preceding or subsequent aspect, further comprising aging the aluminum alloy product.

Aspect 49 is the method of any preceding or subsequent aspect, further comprising cold rolling the aluminum alloy product.

Aspect 50 is the method of any preceding or subsequent aspect, further comprising hot rolling the aluminum alloy product.

Aspect 51 is the method of any preceding or subsequent aspect, further comprising exposing the aluminum alloy product to an elevated temperature.

Aspect 52 is the method of any preceding or subsequent aspect, further comprising exposing the aluminum alloy product to a corrosive environment.

Aspect 53 is a comparable aluminum alloy product wherein the presence of calcium in the aluminum alloy product comprises from 3% to 10% by weight magnesium or from 6% to 12% by weight sum of zinc, magnesium, and copper, and less than 0.001% calcium by weight. The method of any preceding or subsequent aspect for increasing the amount of time required to induce stress corrosion cracking in an aluminum alloy product in connection with the present invention.

Aspect 54 is the method of any preceding or subsequent aspect, further comprising exposing the aluminum alloy to a marine environment.

Aspect 55 is the method of any preceding aspect, wherein the aluminum alloy product is the stress corrosion cracking-resistant aluminum alloy product of any preceding aspect.

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

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

Claims (30)

A stress corrosion cracking-resistant aluminum alloy product comprising:
A plurality of alloying elements comprising:
3% to 10% by weight of magnesium or 6% to 15% by weight of a total of zinc, magnesium and copper;
0.001 wt% to 0.1 wt% calcium; and
A stress corrosion cracking-resistant aluminum alloy product comprising aluminum. The stress corrosion cracking-resistant aluminum alloy product of claim 1 , wherein the plurality of alloying elements further comprises from 0.001 weight percent to 0.1 weight percent strontium. The stress corrosion cracking-resistant aluminum alloy product of claim 1 , wherein the plurality of alloying elements further comprises from 0.001 weight percent to 0.1 weight percent silver. The stress corrosion cracking-resistant aluminum alloy product of claim 1 , in H temper. The stress corrosion cracking-resistant aluminum alloy product of claim 1 , in the T temper. The stress corrosion cracking-resistant aluminum alloy product of claim 1 comprising a 5xxx series aluminum alloy. The stress corrosion cracking-resistant aluminum alloy product of claim 1 , wherein the plurality of alloying elements do not include zinc. The stress corrosion cracking-resistant aluminum alloy product of claim 1 comprising a 7xxx series aluminum alloy. The stress corrosion cracking-resistant aluminum alloy product of claim 1 , wherein the plurality of alloying elements comprises 0.1 wt % to 15 wt % zinc. The stress corrosion cracking-resistant aluminum alloy product of claim 1 , comprising magnesium-containing precipitates. The stress corrosion cracking-resistant aluminum alloy product of claim 10 comprising magnesium and/or aluminum. 11. The method of claim 10, wherein the magnesium-containing precipitate comprises Mg ₅ Al ₈ beta phase particles and the stress corrosion cracking-resistant aluminum alloy product comprises less than 0.05 wt. % by weight of the Mg ₅ Al ₈ beta phase particles. , a stress corrosion crack-resistant aluminum alloy product. The stress corrosion cracking-resistant aluminum alloy product of claim 10 , wherein the magnesium-containing precipitate comprises Mg and/or Zn. The stress corrosion cracking-resistant aluminum of claim 10 , wherein the magnesium-containing precipitate comprises MgZn ₂ eta phase particles and the stress corrosion cracking-resistant aluminum alloy product comprises less than 10% by weight of MgZn ₂ eta phase particles. alloy product. The stress corrosion cracking-resistant aluminum alloy product of claim 10 , wherein the magnesium-containing precipitate comprises calcium. 11. A comparable aluminum alloy product according to claim 10, wherein the presence of calcium comprises less than 0.001 wt% calcium and 3 wt% to 10 wt% magnesium or from 6 wt% to 12 wt% zinc, magnesium and copper total. and reducing the amount of magnesium-containing deposits in the stress corrosion cracking-resistant aluminum alloy product subjected to the same process conditions. The stress corrosion cracking-resistant aluminum alloy product of claim 1 , comprising at least one phase containing calcium, strontium and/or silver at the grain boundaries of the stress corrosion cracking-resistant aluminum alloy product. 18. The product of claim 17, wherein the at least one phase comprises calcium metal. 18. The product of claim 17, wherein the at least one phase comprises strontium metal. 18. The product of claim 17, wherein the at least one phase comprises silver metal. The stress corrosion cracking-resistant aluminum alloy product of claim 17 , wherein one phase of the one or more phases comprises a combination of at least two of calcium, magnesium, strontium, silver, or aluminum. 18. The product of claim 17, wherein one phase of the one or more phases comprises calcium, strontium, silver, aluminum and magnesium. The stress corrosion cracking-resistant aluminum alloy product of claim 17 , wherein the one or more phases at least partially surround magnesium-containing precipitates located at grain boundaries. A method of making a stress corrosion cracking-resistant aluminum alloy product comprising:
providing the aluminum alloy in a molten state as a molten aluminum alloy; and
casting the molten aluminum alloy to form an aluminum alloy product;
The aluminum alloy is:
3 wt% to 10 wt% magnesium or 6 wt% to 12 wt% total of zinc, magnesium and copper;
0.001 wt% to 0.1 wt% calcium; and
A method comprising aluminum. 25. The method of claim 24, further comprising homogenizing the aluminum alloy product to form a homogenized aluminum alloy product. 25. The method of claim 24, further comprising: aging the aluminum alloy product; cold rolling the aluminum alloy product; hot rolling the aluminum alloy product; exposing the aluminum alloy product to elevated temperatures; or subjecting the aluminum alloy product to corrosive properties. The method further comprising one or more of exposing to the environment. 25. The method of claim 24, wherein the presence of calcium in the aluminum alloy product comprises from 3% to 10% by weight magnesium or from 6% to 12% by weight sum of zinc, magnesium, and copper and less than 0.001% calcium by weight. A method of increasing the amount of time required to induce stress corrosion cracking in an aluminum alloy product with respect to the aluminum alloy product. 25. The method of claim 24, further comprising exposing the aluminum alloy to a marine environment. 29. The method of any one of claims 24-28, wherein the aluminum alloy product is the stress corrosion cracking-resistant aluminum alloy product of any one of claims 1-23. 29. The stress corrosion cracking-resistant aluminum alloy product of any one of claims 1-23, prepared according to the method of any one of claims 24-28.

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