Control of aluminum alloy microstructure for improved corrosion resistance and bonding performance

Abstract

To provide aluminum alloy products that generally have a microstructure and composition that resists corrosion.SOLUTION: The corrosion resistance, in turn, allows the aluminum alloy products to exhibit favorable bond durability performance, e.g., when adhesively bonded to another product. The corrosion resistance can be achieved by controlling the composition of the aluminum alloy, including the presence and / or concentration of certain intermetallic particles, such as α-phase intermetallic particles and β-phase intermetallic particles.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of and priority to U.S. Provisional Application No. 62 / 978,767, filed February 19, 2020, U.S. Provisional Application No. 62 / 984,555, filed March 3, 2020, and U.S. Provisional Application No. 62 / 993,365, filed March 23, 2020, which are hereby incorporated by reference in their entireties.

[0002] The present disclosure relates generally to metallurgy, and more specifically to aluminum alloys and aluminum alloy products that exhibit good corrosion resistance and joint durability capabilities. [Background technology]

[0003] Aluminum alloy products, such as sheet metal, can be joined to other products using a variety of techniques. For example, aluminum alloy products may be joined together by welding, riveting, adhesive bonding (e.g., using epoxy adhesives, polyurethane adhesives, phenolic adhesives, or acrylate adhesives), or the like. While welding techniques are typically not applicable for joining aluminum alloy products to other products, such as steel or polymer products, techniques such as riveting or the use of adhesive bonding may be used to join the products together. The bonding performance of various aluminum alloys and aluminum alloy products may depend on various factors, such as composition, processing history, or alloy microstructure. These factors may also affect the corrosion potential of the alloys and products, and corrosion may also be a comprehensive factor in the bonding durability performance of a particular aluminum alloy or product. For example, the sooner corrosion is initiated or occurs at the adhesive bond site, the sooner the bond may fail. Summary of the Invention

[0004] The term "embodiment" and similar terms are intended to broadly refer to the subject matter of this disclosure and all of the following claims. It should be understood that phrases containing these terms are not intended to limit the subject matter described herein or the meaning or scope of the following claims. The embodiments of the disclosure contained herein are defined by the following claims, not this Summary. This Summary is a broad overview of various aspects of the disclosure and introduces some of the concepts that are further described in the Detailed Description section below. This Summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used alone to determine the scope of the claimed subject matter. The subject matter should be understood by reference to the appropriate portions of the entire specification of this disclosure, any or all drawings, and the claims.

[0005] In a first aspect, an aluminum alloy product is disclosed. Examples of the aluminum alloy product may include an aluminum alloy ingot, slab, shate, plate or sheet. The aluminum alloy product may have an alloy composition that allows for good performance in use, for example in a joint arrangement where high joint durability is useful.

[0006] Exemplary aluminum alloy products may include 6xxx series aluminum alloys having a composition of alloying elements adjusted such that the aluminum alloy product exhibits good joint durability. The 6xxx series aluminum alloys may include β-phase intermetallic compound particles and α-phase intermetallic compound particles. In some cases, the β-phase intermetallic compound particles may be characterized and / or exhibit an aspect ratio of greater than about 2, e.g., 1.9-100, 2-5, 5-10, 10-20, 20-50, or 50-100. In some cases, the α-phase intermetallic compound particles may be characterized and / or exhibit an aspect ratio of about 1-1.5, e.g., 0.9-1, 1-1.1, 1.1-1.2, 1.3-1.4, 1.4-1.5, or 1.5-1.6. The β-phase intermetallic compound particles may include aluminum, iron, and silicon. The alpha phase intermetallic particles may include aluminum, silicon, and one or more of iron, manganese, or chromium.

[0007] In some cases, the presence, concentration, or ratio of amounts of β-phase intermetallic particles and α-phase intermetallic particles may affect the usefulness of an aluminum alloy product in a particular application, for example, due to differences in reactivity or corrosion potential between the β-phase intermetallic particles and the α-phase intermetallic particles. For example, the corrosion potential of the β-phase intermetallic particles may be greater than the corrosion potential of the aluminum alloy matrix carrying the β-phase intermetallic particles. As another example, the corrosion potential of the β-phase intermetallic particles may be greater than the corrosion potential of the α-phase intermetallic particles.

[0008] By controlling certain properties of the 6xxx series alloys, the alloys may exhibit certain characteristics, such as corrosion resistance, that may enable better performance in a wide variety of applications. For example, it may be desirable to have a higher concentration of α-phase intermetallic particles than β-phase intermetallic particles in the aluminum alloy. The concentration (e.g., weight percent) of α-phase intermetallic particles and the ratio of weight percent of α-phase intermetallic particles to β-phase intermetallic particles may be determined by a process that includes phase characterization using energy dispersive x-ray spectroscopy (EDXS) compositional analysis. In some examples, the total concentration of α-phase stabilizing alloying elements in the 6xxx series aluminum alloys may be about 0.2 wt.% or more. As another example, the ratio of the total concentration of α-phase stabilizing alloying elements to the amount of excess silicon in the 6xxx series aluminum alloys may be about 1.0 or more. As another example, the ratio of the amount of magnesium in the 6xxx series aluminum alloys to the amount of silicon in the 6xxx series aluminum alloys is about 4.0 or less. As another example, the weight percentage ratio of alpha phase intermetallic grains to beta phase intermetallic grains in the aluminum alloy product may be greater than 2.0.

[0009] As noted above, the aluminum alloy product of this embodiment may exhibit good performance. In some examples, the aluminum alloy product may exhibit bond durability of 30 to 65 cycles or more according to the ASTM D3762 standard test or the FLTM BV 101-07 standard test. These tests may correspond to standard tests used to evaluate bond durability of aluminum alloy products bonded by adhesives, such as epoxy adhesives, polyurethane adhesives, phenolic adhesives, acrylate adhesives, or other adhesives. In some cases, any desired number of cycles may be used to evaluate how durable the bond between the bonded products may be.

[0010] The aluminum alloy products described herein may have any suitable composition, which may reflect the amounts of various alloying elements or grain refiners or other alloying constituents, depending on various parameters. For example, it may be useful to limit the composition of the aluminum alloy in some way, such as to include a minimum or maximum amount of one or more alloying elements. To give a specific example, the aluminum alloy product may be or include a 6xxx series aluminum alloy, which generally represents an alloy that includes more than trace amounts of silicon and magnesium. In some examples, the 6xxx series aluminum alloys may include up to 1.8 wt.% silicon, up to 1.8 wt.% iron, up to 1.5 wt.% copper, up to 0.5 wt.% manganese, 0.2 wt.% to 3.0 wt.% magnesium, up to 0.25 wt.% titanium, up to 1.5 wt.% zinc, up to 1 wt.% nickel, up to 0.25 wt.% vanadium, up to 0.25 wt.% zirconium, up to 0.5 wt.% chromium, and the balance aluminum. Optionally, the 6xxx series aluminum alloys may include up to 0.15 wt.% impurities. In some cases, the 6xxx series aluminum alloys may include up to 0.25 wt.% titanium carbide. Optionally, the parts per million concentration of the carbide grain refiner in the 6xxx series aluminum alloys may be 10 or less. In some cases, the 6xxx series aluminum alloys are free of boron, or are substantially free, meaning that only trace amounts of boron may be present.

[0011] In some cases, the 6xxx series aluminum alloys may include one or more α-phase stabilizing alloying elements totaling about 0.2 wt.% or more (i.e., the sum of the concentrations of all α-phase stabilizing alloying elements may be about 0.2 wt.% or more). In some cases, the α-phase stabilizing alloying elements include copper, chromium, manganese, zirconium, and vanadium. In some cases, the upper limit of the total concentration of the α-phase stabilizing alloying elements may be about 2 wt.% or less. Exemplary total concentrations of all α-phase stabilizing alloying elements may be between 0.2 wt.% and 0.4 wt.%, between 0.2 wt.% and 0.6 wt.%. 0.2wt.%~0.8wt.%, 0.2wt.%~1.0wt.%, 0.2wt.%~1.2wt.%, 0.2wt.%~1.4wt.%, 0.2wt.%~1.6wt.%, 0.2wt.% ~1.8wt.%, 0.2wt.%~2.0wt.%, 0.4wt.%~0.6wt.%, 0.4wt.%~0.8wt.%, 0.4wt.%~1.0wt.%, 0.4wt.%~1.2wt. %, 0.4wt.%~1.4wt.%, 0.4wt.%~1.6wt.%, 0.4wt.%~1.8wt.%, 0.4wt.%~2.0wt.%, 0.6wt.%~0.8wt.%, 0.6wt .%~1.0wt.%, 0.6wt.%~1.2wt.%, 0.6wt.%~1.4wt.%, 0.6wt.%~1.6wt.%, 0.6wt.%~1.8wt.%, 0.6wt.%~2.0w t.%, 0.8wt.%~1.0wt.%, 0.8wt.%~1.2wt.%, 0.8wt.%~1.4wt.%, 0.8wt.%~1.6wt.%, 0.8wt.%~1.8wt.%, 0.8 wt.%~2.0wt.%, 1.0wt.%~1.2wt.%, 1.0wt.%~1.4wt.%, 1.0wt.%~1.6wt.%, 1.0wt.%~1.8wt.%, 1.0wt.%~2. It can be 0wt.%, 1.2wt.%-1.4wt.%, 1.2wt.%-1.6wt.%, 1.2wt.%-1.8wt.%, 1.2wt.%-2.0wt.%, 1.4wt.%-1.6wt.%, 1.4wt.%-1.8wt.%, 1.4wt.%-2.0wt.%, 1.6wt.%-1.8wt.%, 1.6wt.%-2.0wt.%, or 1.8wt.%-2.0wt.%.

[0012] In some cases, the ratio of the total concentration of α-phase stabilizing alloying elements to the amount of excess silicon in a 6xxx series aluminum alloy may be about 1.0 or greater. In some cases, the upper limit of the ratio of the total concentration of α-phase stabilizing alloying elements to the amount of excess silicon may be about 3. Exemplary ratios of the total concentration of α-phase stabilizing alloying elements to the amount of excess silicon in a 6xxx series aluminum alloy may be 1-1.25, 1-1.5, 1-1.75, 1-1.85, 1-1.95, 1-1.10, 1-1.25, 1-1.50, 1-1.75, 1-1.85, 1-1.15, 1-1.16, 1-1.25, 1-1.50, 1-1.25, 1-1.50, 1-1.75, 1-1.16, 1-1.17, 1-1.25, 1-1.50, 1-1.25, 1-1.50, 1-1.75, 1-1.18, 1-1.25, 1-1.50, 1-1.25, 1-1.50, 1-1.75, 1-1.16, 1-1.25, 1-1.50 ...25, 1-1.25, 1-1.25, 1-1.25, 1-1.25, 1-1.25, 1-1.2 1~2, 1~2.25, 1~2.5, 1~2.75, 1~3, 1.25~1.5, 1.25~1.75, 1.25~2, 1.25~2.25, 1.25~2.5, 1.25~2.75, 1.25~3, 1.5~1.75, 1.5~2, 1.5~2.25, 1.5~2.5, 1.5~2.75, 1.5~3, 1.75~2, 1.75~2.25, 1.75~2.5, 1.75~2.75, 1.75~3, 2~2.25, 2~2.5, 2~2.75, 2~3, 2.25~2.5, 2.25~2.75, 2.25~3, 2.5~2.75 It can be 2.5 to 3, or 2.75 to 3.

[0013] Silicon, when present in an aluminum alloy, can combine with magnesium to form magnesium silicide, Mg2Si. Silicon present in an aluminum alloy in excess of the amount required to stoichiometrically form Mg2Si with any magnesium present can be considered excess silicon. In some cases, silicon can combine with other elements in the aluminum alloy, such as iron, manganese, and / or chromium. Thus, the amount of silicon considered excess silicon can be the amount of silicon in excess of that required to combine with magnesium, iron, manganese, and / or chromium. In some examples, the amount of excess silicon in a 6xxx series aluminum alloy can be about 0.1 wt.% or more and about 1.4 wt.% or less. Examples of excess silicon amounts are 0.1wt.%~0.2wt.%, 0.1wt.%~0.3wt.%, 0.1wt.%~0.4wt.%, 0.1wt.%~0.5wt.%, 0.1wt.%~0.6wt.%, 0.1wt.%~0.7wt.%, 0.1wt.%~0.8wt.%, 0.1wt.%~0.9wt.%, 0.1wt.%~1.0wt.%, 0.1wt.%~1.1wt. t.%, 0.1wt.%~1.2wt.%, 0.1wt.%~1.3wt.%, 0.1wt.%~1.4wt.%, 0.2wt.%~0.3wt.%, 0.2wt.%~0.4wt.%, 0 .2wt.%~0.5wt.%, 0.2wt.%~0.6wt.%, 0.2wt.%~0.7wt.%, 0.2wt.%~0.8wt.%, 0.2wt.%~0.9wt.%, 0.2wt. %~1.0wt.%, 0.2wt.%~1.1wt.%, 0.2wt.%~1.2wt.%, 0.2wt.%~1.3wt.%, 0.2wt.%~1.4wt.%, 0.3wt.%~0.4 wt.%, 0.3wt.%~0.5wt.%, 0.3wt.%~0.6wt.%, 0.3wt.%~0.7wt.%, 0.3wt.%~0.8wt.%, 0.3wt.%~0.9wt.%, 0.3wt.%~1.0wt.%, 0.3wt.%~1.1wt.%, 0.3wt.%~1.2wt.%, 0.3wt.%~1.3wt.%, 0.3wt.%~1.4wt.%, 0.4wt .%~0.5wt.%, 0.4wt.%~0.6wt.%, 0.4wt.%~0.7wt.%, 0.4wt.%~0.8wt.%, 0.4wt.%~0.9wt.%, 0.4wt.%~1.0wt.%, 0.4wt.%~1.1wt.%, 0.4wt.%~1.2wt.%, 0.4wt.%~1.3wt.%, 0.4wt.%~1.4wt.%, 0.5wt.%~0.6wt.%, 0.5wt.%~0.7wt .%, 0.5wt.%~0.8wt.%, 0.5wt.%~0.9wt.%, 0.5wt.%~1.0wt.%, 0.5wt.%~1.1wt.%, 0.5wt.%~1.2wt.%, 0.5wt.%~1.3wt.%, 0 .5wt.%~1.4wt.%, 0.6wt.%~0.7wt.%, 0.6wt.%~0.8wt.%, 0.6wt.%~0.9wt.%, 0.6wt.%~1.0wt.%, 0.6wt.%~1.1wt.%, 0.6wt. .%~1.2wt.%, 0.6wt.%~1.3wt.%, 0.6wt.%~1.4wt.%, 0.7wt.%~0.8wt.%, 0.7wt.%~0.9wt.%, 0.7wt.%~1.0wt.%, 0.7wt.%~1 .1wt.%, 0.7wt.%~1.2wt.%, 0.7wt.%~1.3wt.%, 0.7wt.%~1.4wt.%, 0.8wt.%~0.9wt.%, 0.8wt.%~1.0wt.%, 0.8wt.%~1.1w t.%, 0.8wt.%~1.2wt.%, 0.8wt.%~1.3wt.%, 0.8wt.%~1.4wt.%, 0.9wt.%~1.0wt.%, 0.9wt.%~1.1wt.%, 0.9wt.%~1.2wt.%, It can be 0.9wt.%-1.3wt.%, 0.9wt.%-1.4wt.%, 1.0wt.%-1.1wt.%, 1.0wt.%-1.2wt.%, 1.0wt.%-1.3wt.%, 1.0wt.%-1.4wt.%, 1.1wt.%-1.2wt.%, 1.1wt.%-1.3wt.%, 1.1wt.%-1.4wt.%, 1.2wt.%-1.3wt.%, 1.2wt.%-1.4wt.%, or 1.3wt.%-1.4wt.%.

[0014] In some cases, the ratio of the total concentration of α-phase stabilizing alloying elements to the amount of iron in the 6xxx series aluminum alloy may be about 0.5 or greater. The upper limit of the ratio of the total concentration of α-phase stabilizing alloying elements to the amount of iron in the 6xxx series aluminum alloy may be about 8. Exemplary ratios of the total concentration of α-phase stabilizing alloying elements to the amount of iron in the 6xxx series aluminum alloy may be 0.5-1, 0.5-1.5, 0.5-2, 0.5-2.5, 0.5-3, 0.5-3.5, 0.5-4, 0.5-4.5, 0.5-5, 0.5-5.5, 0.5-6, 0.5-6.5, 0.5-7, 0.5-7.5, 0.5-8, 1-1.5, 1-2, 1-2.5, 1-3, 1-3.5, 1-4, 1-4.5, 1-5, 1-6, 1-7, 1-8, 1-9, 1-10, 1-11, 1-12, 1-13, 1-14, 1-15, 1-16, 1-17, 1-18, 1-19, 1-20, 1-21, 1-22, 1-23, 1-24, 1-25, 1-26, 1-27, 1-28, 1-29, 1-30, 1-31, 1-32, 1-33, 1-34, 1-35, 1-36, 1-37, 1-38, 1-39, 1-40, 1-41, 1-42, 1- ~5.5, 1~6, 1~6.5, 1~7, 1~7.5, 1~8, 1.5~2, 1.5~2.5, 1.5~3, 1.5~3.5, 1.5~4, 1.5~4.5, 1.5~5, 1.5~5.5, 1.5~6, 1.5~6.5, 1.5~7, 1.5~7.5, 1.5~8, 2~2.5, 2~3, 2~3.5, 2~4, 2~4.5, 2~5, 2~5.5, 2~6, 2~6.5, 2~7, 2~7.5, 2~8, 2.5~3, 2.5~3.5, 2 .5~4, 2.5~4.5, 2.5~5, 2.5~5.5, 2.5~6, 2.5~6.5, 2.5~7, 2.5~7.5, 2.5~8, 3~3.5, 3~4, 3~4.5, 3~5, 3~5.5, 3~6, ​​3~6.5, 3~7, 3~7.5, 3~8, 3.5~4, 3.5~4.5, 3.5~5, 3.5~5.5, 3.5~6, 3.5~6.5, 3.5~7, 3.5~7.5, 3.5~8, 4~4.5, 4~5, 4~5.5, 4~6, 4 It can be 6.5, 4 to 7, 4 to 7.5, 4 to 8, 4.5 to 5, 4.5 to 5.5, 4.5 to 6, 4.5 to 6.5, 4.5 to 7, 4.5 to 7.5, 4.5 to 8, 5 to 5.5, 5 to 6, 5 to 6.5, 5 to 7, 5 to 7.5, 5 to 8, 5.5 to 6, 5.5 to 6.5, 5.5 to 7, 5.5 to 7.5, 5.5 to 8, 6 to 6.5, 6 to 7, 6 to 7.5, 6 to 8, 6.5 to 7, 6.5 to 7.5, 6.5 to 8, 7 to 7.5, 7 to 8, or 7.5 to 8.

[0015] In some cases, the aluminum alloy products described herein may exhibit good joint durability performance that may result from the corrosion potential or corrosion susceptibility of the aluminum alloy product. In some examples, the aluminum alloy products described herein may exhibit reduced corrosion potential compared to a comparable aluminum alloy product, such as one comprising a comparable 6xxx series aluminum alloy having a total concentration of alpha phase stabilizing alloying elements less than 0.5 wt.% and having a comparable weight percent ratio of alpha phase intermetallic particles to beta phase intermetallic particles in the comparable aluminum alloy of less than 1.

[0016] The aluminum alloy products described herein may exhibit good bond durability performance, and thus a bonded aluminum alloy product may include any of the aluminum alloy products described herein bonded to a second product, such as another aluminum alloy product, by an adhesive. Such bonded aluminum alloy products may specifically exhibit bond durability of 30 to 65 cycles or more according to the ASTM D3762 standard test or the FLTM BV 101-07 standard test.

[0017] In another aspect, a method of making an aluminum alloy product is also described herein. The method of this aspect may include, for example, making an aluminum alloy product including a 6xxx series aluminum alloy, and subjecting the aluminum alloy product to processing conditions that modify or control the weight percent ratio of alpha phase intermetallic particles to beta phase intermetallic particles in the aluminum alloy product to greater than 2. By way of example, the total concentration of alpha phase stabilizing alloying elements in the 6xxx series aluminum alloy may be about 0.2 wt.% or greater before being subjected to the processing conditions. By way of example, the ratio of the total concentration of alpha phase stabilizing alloying elements to the amount of excess silicon in the 6xxx series aluminum alloy may be about 1.0 or greater before being subjected to the processing conditions. By way of example, the ratio of the amount of magnesium in the 6xxx series aluminum alloy to the amount of silicon in the 6xxx series aluminum alloy may be about 4.0 or less. Such methods may be useful for producing the aluminum alloy products described herein in various embodiments.

[0018] Other objects and advantages will become apparent from the following detailed description of non-limiting examples.

[0019] DETAILED DESCRIPTION OF THE DRAWINGS This specification refers to the following accompanying drawings, in which the use of like reference numbers in different drawings is intended to indicate like or similar components. [Brief description of the drawings]

[0020] [Figure 1] 1 shows a schematic diagram of an example of a method for making an aluminum alloy product. [Diagram 2] 1 shows a flow chart outlining an example of a method for characterizing an aluminum alloy product. [Diagram 3] FIG. 1 shows a schematic diagram of an example of an aluminum alloy product adhesively bonded to another product. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Described herein are aluminum alloy products that generally have microstructures and compositions that resist corrosion. This corrosion resistance, in turn, enables the aluminum alloy products to exhibit beneficial bond durability capabilities while also exhibiting beneficial mechanical properties, such as when adhesively bonded to another product (e.g., another aluminum alloy product).

[0022] Specifically, the aluminum alloy products of the present disclosure include 6xxx series aluminum alloys (also referred to herein as 6000 series aluminum alloys), which may contain aluminum (Al), silicon (Si), iron (Fe), copper (Cu), manganese (Mn), magnesium (Mg), titanium (Ti), zinc (Zn), nickel (Ni), and / or chromium (Cr) in desired amounts and proportions. Exemplary 6xxx series aluminum alloy compositions optionally include up to 1.8 wt.% silicon, up to 1.8 wt.% iron, up to 1.5 wt.% copper, up to 0.5 wt.% manganese, 0.2-3.0 wt.% magnesium, up to 0.25 wt.% titanium, up to 1.5 wt.% zinc, up to 1 wt.% nickel, up to 0.25 wt.% vanadium, up to 0.25 wt.% zirconium, up to 0.5 wt.% chromium, up to 0.15 wt.% impurities, and balance aluminum. The aluminum alloy products of the present disclosure may include various intermetallic compound particles, such as beta-phase intermetallic compound particles and alpha-phase intermetallic compound particles. Optionally, the alpha-phase intermetallic compound particles and the beta-phase intermetallic compound particles may include aluminum, iron, manganese, and / or silicon, among others.

[0023] The presence of high number density, weight percentage, or high volume percentage of intermetallic particles in aluminum alloy products, including 6xxx series aluminum alloys, may result in aluminum alloy products exhibiting adverse corrosion characteristics and even poor joint qualities, for example, for joints employing polymer adhesives (e.g., epoxy adhesives, polyurethane adhesives, phenolic adhesives, or acrylate adhesives). In particular, β-phase intermetallic particles may exhibit a higher cathodic potential with respect to the surrounding base metal in the aluminum alloy product and may act as active sites for initiating corrosion (e.g., pitting corrosion). On the other hand, although α-phase intermetallic particles may still act as active sites for corrosion, corrosion initiation and propagation in α-phase intermetallic particles may occur at a much slower rate than occurs in β-phase intermetallic particles. In general, 6xxx series aluminum alloys characterized by fewer β-phase intermetallic particles and more α-phase intermetallic particles may tend to undergo slower corrosion and / or exhibit better joint durability than 6xxx series aluminum alloys characterized by fewer α-phase intermetallic particles and more β-phase intermetallic particles.

[0024] In embodiments, the composition of the 6xxx series aluminum alloys may affect the relative proportions of alpha and beta phase intermetallic compound particles created during production of the aluminum alloy product, e.g., during casting processes, homogenization processes, heat treatment processes, etc. Although the aluminum alloy products described herein include those containing 6xxx series aluminum alloys that typically form more beta than alpha phase intermetallic compound particles during production by conventional or typical casting processing methods, the aluminum alloy products of the present disclosure actually exhibit more alpha than beta phase intermetallic compound particles. Stated another way, some 6xxx series aluminum alloys may have compositions that tend to have more β-phase intermetallic grains than α-phase intermetallic grains when produced according to conventional or typical casting processing methods, but these 6xxx series aluminum alloy compositions may contain more α-phase intermetallic grains than β-phase intermetallic grains, for example, when processed differently or by modifying the composition in some way.

[0025] The amount, ratio and size of the α-phase intermetallic grains and the β-phase intermetallic grains may be modified using a number of techniques, including adjusting the overall composition of the alloy as described above, and additionally or alternatively controlling the wide variety of processing conditions to which the aluminum alloy product is subjected (e.g., casting conditions, homogenizing conditions, rolling conditions, etching conditions, heat treating conditions, etc.) Aluminum alloy products of the present disclosure having a higher relative amount of α-phase intermetallic grains compared to β-phase intermetallic grains may exhibit good corrosion resistance and beneficial bond durability capabilities.

[0026] Definitions and Explanations: As used herein, the terms "invention," "the invention," "this invention," and "the present invention" are intended to broadly refer to all of the subject matter of this patent application and the claims that follow. It is to be understood that phrases containing these terms are not intended to limit the subject matter described herein or to limit the meaning or scope of the claims that follow.

[0027] In this description, alloys are identified by their AA number and other related designations, such as "series" or "6xxx." For an understanding of the numbering systems most commonly used in naming and identifying aluminum and its alloys, please refer to "International Alloy Designations and Chemical Composition Limits for Wrought Aluminum and Wrought Aluminum Alloys" or "Registration Record of Aluminum Association Alloy Designations and Chemical Composition Limits for Aluminum Alloys in the Form of Castings and Ingot," both published by The Aluminum Association.

[0028] As used herein, a flat plate typically has a thickness of greater than about 15 mm. For example, a flat plate can refer to an aluminum product having a thickness of greater than about 15 mm, greater than about 20 mm, greater than about 25 mm, greater than about 30 mm, greater than about 35 mm, greater than about 40 mm, greater than about 45 mm, greater than about 50 mm, or greater than about 100 mm.

[0029] As used herein, a shade (also called sheet metal) typically has a thickness of about 4 mm to about 15 mm. For example, the shade may have a thickness of about 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, about 11 mm, about 12 mm, about 13 mm, about 14 mm, or about 15 mm.

[0030] As used herein, sheet metal generally refers to an aluminum product having a thickness of less than about 4 mm. For example, sheet metal may have a thickness of less than about 4 mm, less than about 3 mm, less than about 2 mm, less than about 1 mm, less than about 0.5 mm, or less than about 0.3 mm (e.g., about 0.2 mm).

[0031] Reference may be made herein to alloy tempers or conditions. For an understanding of the most commonly used alloy temper designations, refer to American National Standards (ANSI) H35 on Alloy and Temper Designation Systems. The F condition or temper refers to the aluminum alloy as produced. The O condition or temper refers to the aluminum alloy after annealing. The Hxx condition or temper, also referred to herein as H temper, refers to non-heat treatable aluminum alloys after cold rolling with or without heat treatment (e.g., annealing). Suitable H tempers include tempers HX1, HX2, HX3 HX4, HX5, HX6, HX7, HX8, or HX9. The T1 condition or temper refers to an aluminum alloy that has been cooled from hot working and naturally aged (e.g., at room temperature). The T2 condition or temper refers to an aluminum alloy that has been cooled from hot working, cold worked, and naturally aged. The T3 condition or temper refers to an aluminum alloy that has been solution heat treated, cold worked, and naturally aged. The T4 condition or temper refers to an aluminum alloy that has been solution heat treated and naturally aged. The T5 condition or temper refers to an aluminum alloy that has been cooled from hot working and artificially aged (at an elevated temperature). The T6 condition or temper refers to an aluminum alloy that has been solution heat treated and artificially aged. The T7 condition or temper refers to an aluminum alloy that has been solution heat treated and artificially overaged. The T8x condition or temper refers to the aluminum alloy that has been solution heat treated, cold worked, and artificially aged. The T9 condition or temper refers to the aluminum alloy that has been solution heat treated, artificially aged, and cold worked. The W condition or temper refers to the aluminum alloy after solution heat treatment.

[0032] As used herein, the terms "cast metal product," "casting," "cast aluminum alloy product," and the like are used interchangeably and refer to products produced by direct chill casting (including direct chill co-casting), semi-continuous casting, continuous casting (including, for example, by use of a twin belt caster, twin roll caster, block caster, or any other continuous casting machine), electromagnetic casting, hot top casting, or any other casting process.

[0033] As used herein, the meaning of "room temperature" can include a temperature of about 15° C. to about 30° C., such as about 15° C., about 16° C., about 17° C., about 18° C., about 19° C., about 20° C., about 21° C., about 22° C., about 23° C., about 24° C., about 25° C., about 26° C., about 27° C., about 28° C., about 29° C., or about 30° C. As used herein, the meaning of "ambient conditions" can include a temperature of about room temperature, a relative humidity of about 20% to about 100%, and an atmospheric pressure of about 975 millibar (mbar) to about 1050 mbar. For example, the relative humidity may be about 20%, about 21%, about 22%, about 23%, about 24%, about 25%, about 26%, about 27%, about 28%, about 29%, about 30%, about 31%, about 32%, about 33%, about 34%, about 35%, about 36%, about 37%, about 38%, about 39%, about 40%, about 41%, about 42%, about 43%, about 44%, about 45%, about 46%, about 47%, about 48%, about 49%, about 50%, about 51%, about 52%, about 53%, about 54%, about 55%, about 56%, about 57%, about 58%, about 59%, about 60%, about The concentration may be 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 value in between. For example, atmospheric pressure can be about 975 mbar, about 980 mbar, about 985 mbar, about 990 mbar, about 995 mbar, about 1000 mbar, about 1005 mbar, about 1010 mbar, about 1015 mbar, about 1020 mbar, about 1025 mbar, about 1030 mbar, about 1035 mbar, about 1040 mbar, about 1045 mbar, about 1050 mbar, or any value in between.

[0034] All ranges disclosed herein should be understood to include any and all subranges subsumed therein. For example, a range stated as "1 to 10" should be considered to include any and all subranges between a minimum of 1 and a maximum of 10 (and including the endpoints), i.e., starting from a minimum of 1 or more, e.g., 1 to 6.1, and ending with a maximum of 10 or less, e.g., 5.5 to 10. Unless otherwise indicated, the phrase "less than" means, when referring to a compositional amount of an element, that the element is optional and includes a zero percent composition of that particular element. Unless otherwise indicated, all compositional percentages are in weight percent (wt.%).

[0035] As used herein, the meanings of "a," "an," and "the" are inclusive of the singular and plural meanings, unless the context clearly indicates otherwise.

[0036] In the following examples, the aluminum alloy products and their components may be described by their elemental composition in weight percent (wt.%). The balance in each alloy is aluminum and impurities totaling a maximum of 0.15 wt.%.

[0037] Incidental elements, such as grain refiners and deoxidizers, or other additives, may be present in the present invention and may themselves impart other characteristics to the alloys described herein without departing from or significantly altering the characteristics of the alloys described herein.

[0038] Small amounts of unavoidable impurities, including substances or elements due to the inherent properties of aluminum or leaching from contact with processing equipment, may be present in the alloy. Some of the alloys described may contain up to about 0.25 wt.% of any element in addition to the alloying elements, incidental elements, and unavoidable impurities.

[0039] Aluminum alloy product and manufacturing method thereof As noted above, in embodiments, the composition of the 6xxx series aluminum alloy may affect the relative proportions of alpha and beta phase intermetallic compound particles present in the aluminum alloy product. For example, the presence and proportions of various alloying elements in the 6xxx series aluminum alloy may tend to stabilize or favor the formation of certain intermetallic compound particles, such as beta or alpha phase intermetallic compound particles, during casting, homogenization, heat treatment, and the like. Additionally or alternatively, the presence of grain refiners may tend to stabilize or favor the formation of certain intermetallic compound particles, such as beta or alpha phase intermetallic compound particles. Thus, some 6xxx series aluminum alloys may exhibit good corrosion resistance and bond durability performance in their as-cast or as-prepared condition, for example, if they contain large amounts of alpha phase stabilizing alloying elements, while other 6xxx series aluminum alloys, for example, those containing small amounts of alpha phase stabilizing alloying elements, may tend to exhibit poor corrosion resistance and bond durability performance in their as-cast or as-prepared condition.

[0040] However, some 6xxx series aluminum alloys containing relatively lower amounts of alpha phase stabilizing alloying constituents or relatively higher amounts of beta phase stabilizing alloying elements can be modified by processing techniques and / or compositional variations in grain refiners (e.g., the use of titanium carbide grain refiners) and concentrations to exhibit beneficial intermetallic grain phases and distributions, which in turn can provide the resulting aluminum alloy products with desired bonding durability and corrosion resistance capabilities.

[0041] By way of non-limiting example, exemplary and non-limiting 6xxx series alloys for use in the methods and products described herein are: AA6101, AA6101A, AA6101B, AA6201, AA6201A, AA6401, AA6501, AA6002, AA6003, AA6103, AA6005, AA6005A, AA6005B, AA6005C, AA6105, AA6205, AA6305, AA6006, AA6106, AA 6206, AA6306, AA6008, AA6009, AA6010, AA6110, AA6110A, AA6011, AA6111, AA6012, AA6012A, AA6013, AA6113, AA6014 , AA6015, AA6016, AA6016A, AA6116, AA6018, AA6019, AA6020, AA6021, AA6022, AA6023, AA6024, AA6025, AA6026, AA60 27, AA6028, AA6031, AA6032, AA6033, AA6040, AA6041, AA6042, AA6043, AA6151, AA6351, AA6351A, AA6451, AA6951, AA 6053, AA6055, AA6056, AA6156, AA6060, AA6160, AA6260, AA6360, AA6460, AA6460B, AA6560, AA6660, AA6061, AA6061A , AA6261, AA6361, AA6162, AA6262, AA6262A, AA6063, AA6063A, AA6463, AA6463A, AA6763, A6963, AA6064, AA6064A, AA6065, AA6066, AA6068, AA6069, AA6070, AA6081, AA6181, AA6181A, AA6082, AA6082A, AA6182, AA6091 or AA6092.

[0042] Exemplary alpha-phase stabilizing alloying elements may include one or more of copper, chromium, manganese, zirconium, and vanadium. When the alpha-phase stabilizing alloying elements are present in a 6xxx series aluminum alloy at low concentrations, e.g., less than 0.2 wt.% total, casting of the 6xxx series aluminum alloy may tend to result in fewer alpha-phase intermetallic grains and more beta-phase intermetallic grains. For example, when making a 6xxx series aluminum alloy having less than about 0.2 wt.% total of alpha-phase stabilizing alloying elements, the amount (e.g., wt.%) of beta-phase intermetallic grains may be greater than the amount (e.g., wt.%) of alpha-phase intermetallic grains. Conversely, when the α-phase stabilizing alloying elements are present in a 6xxx series aluminum alloy in a concentration greater than about 0.2 wt.%, the resulting aluminum alloy product may tend to contain greater amounts of α-phase intermetallic compound particles and lesser amounts of β-phase intermetallic compound particles. Exemplary total concentrations of α-phase stabilizing alloying elements are from about 0.2 wt.% to about 2.0 wt.%, e.g., 0.2 wt.% to 0.3 wt.%, 0.2 wt.% to 0.4 wt.%, 0.2 wt.% to 0.5 wt.%, 0.2 wt.% to 0.6 wt.%, 0.2 wt.% to 0.7 wt.%, 0.2 wt.% to 0.8 wt.%, 0.2 wt.% to 0.9 wt.%, 0.2 wt.% to 1.0 wt.%, 0.2 wt.% to 1.1 wt.%, 0.2 wt.% to 1.2 wt.%, 0.2 wt.% to 1.3 wt.%, 0.2 wt.% to 1.4 wt.%, 0.2 wt.% to 1.5 wt.%, 0.2 wt.% to 1.6 wt.%, 0.2 wt.% to 1.8 wt.%, 0.2 wt.% to 1.9 ...9 wt.%, 0.2 wt.% to 1.9 wt.%, 0.2 wt.% to 1.9 wt.%, 0.2 wt.% to 1.9 wt.%, 0.2 wt.% to 1.9 wt.%, 0.2 wt.% .2wt.%~1.4wt.%, 0.2wt.%~1.5wt.%, 0.2wt.%~1.6wt.%, 0.2wt.%~1.7wt.%, 0.2wt.%~1.8wt.%, 0.2wt.%~1.9wt.%, 0.2wt.%~2.0wt.% , 0.3wt.%~0.4wt.%, 0.3wt.%~0.5wt.%, 0.3wt.%~0.6wt.%, 0.3wt.%~0.7wt.%, 0.3wt.%~0.8wt.%, 0.3wt.%~0.9wt.%, 0.3wt.%~1.0wt .%, 0.3wt.%~1.1wt.%, 0.3wt.%~1.2wt.%, 0.3wt.%~1.3wt.%, 0.3wt.%~1.4wt.%, 0.3wt.%~1.5wt.%, 0.3wt.%~1.6wt.%, 0.3wt.%~1.7 wt.%, 0.3wt.%~1.8wt.%, 0.3wt.%~1.9wt.%, 0.3wt.%~2.0wt.%, 0.4wt.%~0.5wt.%, 0.4wt.%~0.6wt.%, 0.4wt.%~0.7wt.%, 0.4wt.%~0 .8wt.%, 0.4wt.%~0.9wt.%, 0.4wt.%~1.0wt.%, 0.4wt.%~1.1wt.%, 0.4wt.%~1.2wt.%, 0.4wt.%~1.3wt.%, 0.4wt.%~1.4wt.%, 0.4wt.% ~1.5wt.%, 0.4wt.%~1.6wt.%, 0.4wt.%~1.7wt.%, 0.4wt.%~1.8wt.%, 0.4wt.%~1.9wt.%, 0.4wt.%~2.0wt.%, 0.5wt.%~0.6wt.%, 0.5wt.%.<h2 style=";text-align:left;direction:ltr">%~0.7wt.%、0.5wt.%~0.8wt.%、0.5wt.%~0.9wt.%、0.5wt.%~1.0wt.%、0.5w t.%~1.1wt.%、0.5wt.%~1.2wt.%、0.5wt.%~1.3wt.%、0.5wt.%~1.4wt.%、0.5 wt.%~1.5wt.%、0.5wt.%~1.6wt.%、0.5wt.%~1.7wt.%、0.5wt.%~1.8wt.%、0 .5wt.%~1.9wt.%、0.5wt.%~2.0wt.%、0.6wt.%~0.7wt.%、0.6wt.%~0.8wt.%、 0.6wt.%~0.9wt.%、0.6wt.%~1.0wt.%、0.6wt.%~1.1wt.%、0.6wt.%~1.2wt. %、0.6wt.%~1.3wt.%、0.6wt.%~1.4wt.%、0.6wt.%~1.5wt.%、0.6wt.%~1.6wt .%、0.6wt.%~1.7wt.%、0.6wt.%~1.8wt.%、0.6wt.%~1.9wt.%、0.6wt.%~2.0wt.%、0.7wt.%~0.8wt.%、0.7wt.%~0.9wt.%、0.7wt.%~1.0wt.%、0.7wt.%~1. 1wt.%, 0.7wt.%~1.2wt.%, 0.7wt.%~1.3wt.%, 0.7wt.%~1.4wt.%, 0.7wt.%~1.5wt.%, 0.7wt.%~1.6wt.%, 0.7wt.%~1.7wt.%, 0.7wt.%~1.8wt.%, 0.7wt.% ~1.9wt.%、0.7wt.%~2.0wt.%、0.8wt.%~0.9wt.%、0.8wt.%~1.0wt.%、0.8wt .%~1.1wt.%、0.8wt.%~1.2wt.%、0.8wt.%~1.3wt.%、0.8wt.%~1.4wt.%、0.8w t.%~1.5wt.%、0.8wt.%~1.6wt.%、0.8wt.%~1.7wt.%、0.8wt.%~1.8wt.%、0. 8wt.%~1.9wt.%、0.8wt.%~2.0wt.%、0.9wt.%~1.0wt.%、0.9wt.%~1.1wt.%、0 .9wt.%~1.2wt.%、0.9wt.%~1.3wt.%、0.9wt.%~1.4wt.%、0.9wt.%~1.5wt.%、0.9wt.%~1.6wt.%、0.9wt.%~1.7wt.%、0.9wt.%~1.8wt.%、0.9wt.%~1.9wt.%, 0.9wt.%~2.0wt.%, 1.0wt.%~1.1wt.%, 1.0wt.%~1.2wt.%, 1.0wt.%~1.3wt.%, 1.0wt.%~1.4wt.%, 1.0wt.%~1.5wt.%, 1.0wt.%~1.6wt.% , 1.0wt.%~1.7wt.%, 1.0wt.%~1.8wt.%, 1.0wt.%~1.9wt.%, 1.0wt.%~2.0wt.%, 1.1wt.%~1.2wt.%, 1.1wt.%~1.3wt.%, 1.1wt.%~1.4wt.%, 1.1wt.%~1.5wt.%, 1.1wt.%~1.6wt.%, 1.1wt.%~1.7wt.%, 1.1wt.%~1.8wt.%, 1.1wt.%~1.9wt.%, 1.1wt.%~2.0wt.%, 1.2wt.%~1.3wt.%, 1 .2wt.%~1.4wt.%, 1.2wt.%~1.5wt.%, 1.2wt.%~1.6wt.%, 1.2wt.%~1.7wt.%, 1.2wt.%~1.8wt.%, 1.2wt.%~1.9wt.%, 1.2wt.%~2.0wt.%, 1.3 wt.%~1.4wt.%, 1.3wt.%~1.5wt.%, 1.3wt.%~1.6wt.%, 1.3wt.%~1.7wt.%, 1.3wt.%~1.8wt.%, 1.3wt.%~1.9wt.%, 1.3wt.%~2.0wt.%, 1.4w t.%~1.5wt.%, 1.4wt.%~1.6wt.%, 1.4wt.%~1.7wt.%, 1.4wt.%~1.8wt.%, 1.4wt.%~1.9wt.%, 1.4wt.%~2.0wt.%, 1.5wt.%~1.6wt.%, 1.5wt It can be 1.6wt.% to 1.7wt.%, 1.5wt.% to 1.8wt.%, 1.5wt.% to 1.9wt.%, 1.5wt.% to 2.0wt.%, 1.6wt.% to 1.7wt.%, 1.6wt.% to 1.8wt.%, 1.6wt.% to 1.9wt.%, 1.6wt.% to 2.0wt.%, 1.7wt.% to 1.8wt.%, 1.7wt.% to 1.9wt.%, 1.7wt.% to 2.0wt.%, 1.8wt.% to 1.9wt.%, 1.8wt.% to 2.0wt.%, or 1.9wt.% to 2.0wt.%.

[0043] Another example of an ingredient that influences intermetallic grain formation may include excess silicon. Silicon is commonly present in many aluminum alloys. When included in magnesium-containing aluminum alloys, the amount of silicon in excess of that required to stoichiometrically combine with magnesium as the compound Mg2Si may be considered excess silicon. In some cases, the amount of silicon considered excess silicon may be the amount of silicon in excess of that required to combine with magnesium, iron, manganese, and / or chromium. In one example, the amount of excess silicon is defined as: excess silicon=(wt.% silicon)-(wt.% magnesium) / 1.78-(wt.% iron+manganese+chromium) / 6. Excess silicon in 6xxx series aluminum alloys may tend to favor or stabilize the formation of β-phase intermetallic grains. Exemplary 6xxx series aluminum alloys described herein may have a Cr content of about 0.1 wt.% to about 1.4 wt.%, for example, 0.1 wt.% to 0.2 wt.%, 0.1 wt.% to 0.3 wt.%, 0.1 wt.% to 0.4 wt.%, 0.1 wt.% to 0.5 wt.%, 0.1 wt.% to 0.6 wt.%, 0.1 wt.% to 0.7 wt.%, 0.1 wt.% to 0.8 wt.%. wt.%, 0.1wt.%~0.9wt.%, 0.1wt.%~1.0wt.%, 0.1wt.%~1.1wt.%, 0.1wt.%~1.2wt.%, 0.1wt.%~1 .3wt.%, 0.1wt.%~1.4wt.%, 0.2wt.%~0.3wt.%, 0.2wt.%~0.4wt.%, 0.2wt.%~0.5wt.%, 0.2wt.%~ 0.6wt.%, 0.2wt.%~0.7wt.%, 0.2wt.%~0.8wt.%, 0.2wt.%~0.9wt.%, 0.2wt.%~1.0wt.%, 0.2wt. %~1.1wt.%, 0.2wt.%~1.2wt.%, 0.2wt.%~1.3wt.%, 0.2wt.%~1.4wt.%, 0.3wt.%~0.4wt.%, 0.3wt .%~0.5wt.%, 0.3wt.%~0.6wt.%, 0.3wt.%~0.7wt.%, 0.3wt.%~0.8wt.%, 0.3wt.%~0.9wt.%, 0.3 wt.%~1.0wt.%, 0.3wt.%~1.1wt.%, 0.3wt.%~1.2wt.%, 0.3wt.%~1.3wt.%, 0.3wt.%~1.4wt.%, 0.4wt.%~0.5wt.%, 0.4wt.%~0.6wt.%, 0.4wt.%~0.7wt.%, 0.4wt.%~0.8wt.%, 0.4wt.%~0.9wt.%, 0.4wt.%~1.0wt.%, 0.4wt.%~1.1wt.%, 0 .4wt.%~1.2wt.%, 0.4wt.%~1.3wt.%, 0.4wt.%~1.4wt.%, 0.5wt.%~0.6wt.%, 0.5wt.%~0.7wt.%, 0.5wt.%~0.8wt.%, 0.5wt.%~0.9wt.%, 0 .5wt.%~1.0wt.%, 0.5wt.%~1.1wt.%, 0.5wt.%~1.2wt.%, 0.5wt.%~1.3wt.%, 0.5wt.%~1.4wt.%, 0.6wt.%~0.7wt.%, 0.6wt.%~0.8wt.%, 0.6wt.%~0.9wt.%, 0.6wt.%~1.0wt.%, 0.6wt.%~1.1wt.%, 0.6wt.%~1.2wt.%, 0.6wt.%~1.3wt.%, 0.6wt.%~1.4wt.%, 0.7wt.%~0.8wt.%, 0.7wt.%~0.9wt.%, 0.7wt.%~1.0wt.%, 0.7wt.%~1.1wt.%, 0.7wt.%~1.2wt.%, 0.7wt.%~1.3wt.%, 0.7wt.%~1.4wt.%, 0.8wt.%~0.9wt.% , 0.8wt.%~1.0wt.%, 0.8wt.%~1.1wt.%, 0.8wt.%~1.2wt.%, 0.8wt.%~1.3wt.%, 0.8wt.%~1.4wt.%, 0.9wt.%~1.0wt.%, 0.9wt.%~1.1wt.% , 0.9wt.% to 1.2wt.%, 0.9wt.% to 1.3wt.%, 0.9wt.% to 1.4wt.%, 1.0wt.% to 1.1wt.%, 1.0wt.% to 1.2wt.%, 1.0wt.% to 1.3wt.%, 1.0wt.% to 1.4wt.%, 1.1wt.% to 1.2wt.%, 1.1wt.% to 1.3wt.%, 1.1wt.% to 1.4wt.%, 1.2wt.% to 1.3wt.%, 1.2wt.% to 1.4wt.%, or 1.3wt.% to 1.4wt.% of excess silicon.

[0044] In embodiments, the presence of relatively greater amounts of alpha-phase stabilizing alloying elements and relatively greater amounts of excess silicon may tend to cancel each other out with respect to the ratio of alpha-phase intermetallic grains to beta-phase intermetallic grains in a 6xxx series aluminum alloy. Thus, it may also or alternatively be desirable to characterize a 6xxx series aluminum alloy by the ratio of the total concentration of alpha-phase stabilizing alloying elements to the amount of excess silicon. In embodiments, when this ratio is greater than about 1.0 in a 6xxx series aluminum alloy, alpha-phase intermetallic grains may be nominally favored over beta-phase intermetallic grains. Example ratios of the total concentration of α-phase stabilizing alloying elements to the amount of excess silicon are 1.0-1.25, 1.0-1.5, 1.0-1.75, 1.0-2.0, 1.0-2.25, 1.0-2.5, 1.0-2.75, 1.0-3.0, 1.0-3.25, 1.0-3.5, 1.0-3.75, 1.0-4.0, 1.0-4.25, 1.0-4.5, 1.0-4.75, 1.0-5.0, 1.25-1.5, 1.0-5.0 ... .25~1.75, 1.25~2.0, 1.25~2.25, 1.25~2.5, 1.25~2.75, 1.25~3.0, 1.25~3.25, 1.25~3.5, 1.25~3.75, 1.25~4.0, 1.25~4.25, 1.25~4.5, 1.25~4.75, 1.25~5.0, 1.5~1.75, 1.5~2.0, 1.5~2.25, 1.5~2.5, 1.5~2.75, 1.5~3. 0, 1.5~3.25, 1.5~3.5, 1.5~3.75, 1.5~4.0, 1.5~4.25, 1.5~4.5, 1.5~4.75, 1.5~5.0, 1.75~2.0, 1.75~2.25, 1.75~2.5, 1.75~2.75, 1.75~3.0, 1.75~3.25, 1.75~3.5, 1.75~3.75, 1.75~4.0, 1.75~4.25, 1.75~4.5, 1.75~4. 75, 1.75~5.0, 2.0~2.25, 2.0~2.5, 2.0~2.75, 2.0~3.0, 2.0~3.25, 2.0~3.5, 2.0~3.75, 2.0~4.0, 2.0~4.25, 2.0~4.5, 2.0~4.75, 2.0~5.0, 2.25~2.5, 2.25~2.75, 2.25~3.0, 2.25~3.25, 2.25~3.5, 2.25~3.75, 2.25~4.0, 2.25~4.25, 2.25~4.5, 2.25~4.75, 2.25~5.0, 2.5~2.75, 2.5~3.0, 2.5~3.25, 2.5~3.5, 2.5~3.75, 2.5~4.0, 2.5~4.25, 2.5~4.5, 2.5~4.75, 2.5~5.0, 2.75~3.0, 2.7 5~3.25, 2.75~3.5, 2.75~3.75, 2.75~4.0, 2.75~4.25, 2.75~4.5, 2.75~4.75, 2.75~5.0, 3.0~3.25, 3.0~3.5, 3.0~3.75, 3.0~4.0, 3.0~4.25, 3.0~4.5, 3.0~4.75, 3 .0~5.0, 3.25~3.5, 3.25~3.75, 3.25~4.0, 3.25~4.25, 3.25~4.5, 3.25~4.75, 3.25~5.0, 3.5~3.75, 3.5~4.0, 3.5~4.25, 3.5~4.5, 3.5~4.75, 3.5~5.0, 3.75~4.0, It can be 3.75-4.25, 3.75-4.5, 3.75-4.75, 3.75-5.0, 4.0-4.25, 4.0-4.5, 4.0-4.75, 4.0-5.0, 4.25-4.5, 4.25-4.75, 4.25-5.0, 4.5-4.75, 4.5-5.0, or 4.75-5.0.

[0045] In an embodiment, the ratio of the concentrations of magnesium and silicon may be used to modify or effect the relative amounts of α and β phase intermetallic grains in the 6xxx series aluminum alloys. Example ratios of magnesium to silicon concentrations are: 0.25~0.5, 0.25~0.75, 0.25~1.0, 0.25~1.25, 0.25,~1.5, 0.25~1.75, 0.25~2.0, 0.25~2.25, 0.25~2.5, 0.25~2.75, 0.25~3.0, 0.25~3.25, 0.25~3.5, 0.25~3.75, 0.25~4.0, 0.5~0.75, 0.5,~1.0, 0.5~1.25, 0.5~1.5, 0.5~1.75, 0.5~2.0, 0.5~ 2.25, 0.5~2.5, 0.5~2.75, 0.5~3.0, 0.5~3.25, 0.5~3.5, 0.5~3.75, 0.5~4.0, 0.75~1.0, 0.75~1.25, 0.75~1.5, 0.75~1.75, 0.75~2, 0.75~2.25, 0.75~2.5, 0.75~2.75, 0.75~3, 0.75~3.25, 0.75~3.5, 0.75~3.75, 0.75~4.0, 1.0~1.25, 1.0~1.5, 1.0~1.75, 1.0~2.0, 1.0~2.25 , 1.0~2.5, 1.0~2.75, 1.0~3.0, 1.0~3.25, 1.0~3.5, 1.0~3.75, 1.0~4.0, 1.25~1.5, 1.25~1.75, 1.25~2.0, 1.25~2.25, 1.25~2.5, 1.25~2.75, 1.25~3.0, 1.25~3.25, 1.25~3.5, 1.25~3.75, 1.25~4.0, 1.5~1.75, 1.5~2.0, 1.5~2.25, 1.5~2.5, 1.5~2.75, 1.5~3.0, 1.5~3.25, 1 .5~3.5, 1.5~3.75, 1.5~4.0, 1.75~2.0, 1.75~2.25, 1.75~2.5, 1.75~2.75, 1.75~3.0, 1.75~3.25, 1.75~3.5, 1.75~3.75, 1.75~4.0, 2.0~2.25, 2.0~2.5, 2.0~2.75, 2.0~3.0, 2.0~3.25, 2.0~3.5, 2.0~3.75, 2.0~4.0, 2.25~2.5, 2.25~2.75, 2.25~3.0, 2.25~3.25, 2.25~3.5, 2.It can be 25-3.75, 2.25-4.0, 2.5-2.75, 2.5-3.0, 2.5-3.25, 2.5-3.5, 2.5-3.75, 2.5-4.0, 2.75-3.0, 2.75-3.25, 2.75-3.5, 2.75-3.75, 2.75-4.0, 3.0-3.25, 3.0-3.5, 3.0-3.75, 3.0-4.0, 3.25-3.5, 3.25-3.75, 3.25-4.0, 3.5-3.75, 3.5-4.0, or 3.75-4.0.

[0046] In some cases, the composition and concentration of grain refiners may also contribute to the formation of various intermetallic grain phases. For example, boron grain refiners may promote the formation of β-phase intermetallic grains, and therefore it may be desirable to reduce, eliminate, or avoid boron grain refiners in the alloy composition. Optionally, the 6xxx series aluminum alloys used may be those that do not contain boron grain refiners or contain only relatively small amounts, such as less than 0.15 wt.%, of boron grain refiners. In some examples, the 6xxx series aluminum alloys are free or substantially free of boron. In contrast, carbide grain refiners may promote the formation of α-phase intermetallic grains, and therefore it may be desirable to add or use carbide grain refiners in the alloy composition instead. Optionally, the 6xxx series aluminum alloys used may contain up to 10 parts per million of carbide grain refiners.

[0047] As noted above, a greater relative amount of β-phase intermetallic particles than α-phase intermetallic particles can contribute to poor corrosion resistance and / or poor joint durability performance in some aluminum alloy products. In some embodiments, 6xxx series aluminum alloys having an overall composition that favors the formation of β-phase intermetallic particles during conventional fabrication can be modified to increase the relative amount of α-phase intermetallic particles and decrease the relative amount of β-phase intermetallic particles to result in aluminum alloy products exhibiting better corrosion resistance and better joint durability. For example, casting practices (e.g., casting temperature, casting speed, casting geometry), homogenization practices (e.g., homogenization time, homogenization temperature), rolling practices (e.g., number of hot rolling passes, thickness reduction during each hot rolling pass, temperature during each hot rolling pass, number of cold rolling passes, thickness reduction during cold rolling pass, temperature during each cold rolling pass), annealing and heat treatment practices (e.g., annealing or heat treatment time, annealing or heat treatment temperature, quenching temperature, quenching rate), etc., may be modified to favor the formation of alpha phase intermetallic grains over beta phase intermetallic grains.

[0048] Advantageously, in embodiments of the aluminum alloy products of the present disclosure, the weight percentage ratio of α-phase intermetallic grains to β-phase intermetallic grains may be about 1 or greater, about 2 or greater, about 3 or greater, or between 1.0 and 100.

[0049] The alpha and beta intermetallic particles in the aluminum alloy product may have any suitable dimensions. For example, the mean or median size (e.g., cross-sectional dimension, diameter, etc.) of the alpha or beta intermetallic particles may be between 3 μm and 5 μm. Typically, the alpha or beta intermetallic particles may have a more spherical shape than the beta intermetallic particles, while the beta intermetallic particles may have a more plate-like or acicular shape than the alpha intermetallic particles. The shape of the alpha or beta intermetallic particles may be characterized by the aspect ratio of the particle, e.g., the ratio of the length of the longest dimension of the particle to the length of the shortest dimension of the particle. By way of example, the alpha intermetallic particles may be characterized by an aspect ratio of 1 to 1.5, and the beta intermetallic particles may be characterized by an aspect ratio of greater than 2 (e.g., 2 to 100).

[0050] The aluminum alloy product may have any suitable material properties, such as ultimate tensile strength, yield strength, uniform elongation, total elongation, etc. As an example, the aluminum alloy product of the present disclosure may have an ultimate tensile strength between 200 MPa and 450 MPa. As another example, the aluminum alloy product of the present disclosure may have a yield strength between 100 MPa and 400 MPa. As another example, the aluminum alloy product of the present disclosure may have a uniform elongation between 18% and 28%. As another example, the aluminum alloy product of the present disclosure may have a total elongation between 20% and 32%.

[0051] The aluminum alloy products described herein may be made using any suitable method. For example, the aluminum alloy products may be cast, homogenized, hot rolled, cold rolled, heat treated, formed, etc. In some cases, the aluminum alloy products may be subjected to processing conditions that modify or control the weight percentage ratio of alpha phase intermetallic particles to beta phase intermetallic particles in the aluminum alloy product to be greater than 1. A detailed description of examples of methods for making the aluminum alloy products of the present disclosure is provided in U.S. Provisional Application No. 62 / 984,675, filed March 3, 2020, which is hereby incorporated by reference in its entirety.

[0052] FIG. 1 shows a schematic diagram of an example of a method for making an aluminum alloy product. The method of FIG. 1 begins at 105, where an aluminum alloy 106 is cast to form a cast aluminum alloy product 107, such as an ingot or other casting. At 110, the cast aluminum alloy product 107 is homogenized to form a homogenized aluminum alloy product 111. In some cases, the homogenization and casting processes are combined as casting with in situ homogenization. At 115, the homogenized aluminum alloy product 111 is subjected to one or more hot rolling passes and / or one or more cold rolling passes to form a rolled aluminum alloy product 112, which may correspond to an aluminum alloy article, such as an aluminum alloy plate, aluminum alloy shade, or aluminum alloy sheet. Optionally, the rolled aluminum alloy product 112 is subjected to a solution heat treatment and / or one or more forming or stamping processes to form an aluminum alloy article.

[0053] Non-limiting examples of casting processes include a direct chill (DC) casting process or a continuous casting (CC) process. For example, FIG. 1 depicts a schematic diagram of a DC casting process at 105. A continuous casting system may include a pair of moving opposed casting surfaces (e.g., moving opposed belts, rolls, or blocks), a pouring cavity between the pair of moving opposed casting surfaces, and a pourer. The pourer may have an end opening through which molten metal may exit the pourer and be poured into the pouring cavity.

[0054] Cast aluminum alloy products, such as cast ingots or other castings, may be processed by any means known to those skilled in the art. Optionally, processing steps to produce sheet metal may be used. Exemplary optional processing steps include, but are not limited to, homogenization, hot rolling, cold rolling, annealing, solution heat treatment, and preaging.

[0055] In the homogenization step, the cast product may be heated to a temperature ranging from about 400°C to about 600°C. For example, the cast product may be heated to a temperature of about 400°C, about 410°C, about 420°C, about 430°C, about 440°C, about 450°C, about 460°C, about 470°C, about 480°C, about 490°C, about 500°C, about 510°C, about 520°C, about 530°C, about 540°C, about 550°C, about 560°C, about 570°C, about 580°C, about 590°C, or about 600°C. The product may then be soaked (i.e., held at a specified temperature) for a period of time to form a homogenized product. In some examples, the total time of the homogenization step, including the heating and soaking periods, may be 24 hours or less. For example, the product may be heated and soaked to 500°C to 600°C for a total time of 18 hours or less for the homogenization step. Optionally, the product may be heated to less than 490°C and soaked for a total time of more than 18 hours for the homogenization step. In some cases, the homogenization step includes multiple processes. In some non-limiting examples, the homogenization step includes heating the casting 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 casting may be heated to about 465°C for about 3.5 hours, and then heated to about 480°C for about 6 hours.

[0056] Following the homogenization step, a hot rolling step may optionally be performed. Before starting the hot rolling, the homogenized product may be cooled to a temperature of 300°C to 450°C. For example, the homogenized product may be cooled to a temperature of 325°C to 425°C, or 350°C to 400°C. The homogenized product may then be hot rolled at a temperature of 300°C to 450°C to form a hot rolled plate, hot rolled sheet, or hot rolled sheet having standard dimensions of 3 mm to 200 mm (e.g., 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm, 95 mm, 100 mm, 110 mm, 120 mm, 130 mm, 140 mm, 150 mm, 160 mm, 170 mm, 180 mm, 190 mm, 200 mm, or any value in between).

[0057] Optionally, the casting may be a continuous casting that may be cooled to a temperature of 300° C. to 450° C. For example, the continuous casting may be cooled to a temperature of 325° C. to 425° C., or 350° C. to 400° C. The continuous cast product may then be hot rolled at a temperature of 300°C to 450°C to form a hot rolled plate, hot rolled sheet, or hot rolled sheet having standard dimensions of 3 mm to 200 mm (e.g., 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm, 95 mm, 100 mm, 110 mm, 120 mm, 130 mm, 140 mm, 150 mm, 160 mm, 170 mm, 180 mm, 190 mm, 200 mm, or any value in between). During hot rolling, the temperature and other operating parameters may be controlled so that the temperature of the hot rolled intermediate product upon exiting the hot rolling mill is 470°C or less, 450°C or less, 440°C or less, or 430°C or less.

[0058] The cast, homogenized or hot rolled product may optionally be cold rolled using a cold rolling mill to produce a thinner product, such as a cold rolled sheet. The cold rolled product may have a standard dimension of about 0.5-10 mm, such as about 0.7-6.5 mm. Optionally, the cold rolled product may have a standard dimension of 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm or 10.0 mm. Cold rolling may be performed to result in a final gauge corresponding to a gauge reduction of 85% or less (e.g., a reduction of 10% or less, 20% or less, 30% or less, 40% or less, 50% or less, 60% or less, 70% or less, 80% or less, or 85% or less) compared to the gauge before the start of cold rolling. An intermediate annealing step may be optionally performed during the cold rolling process, such as when a cold rolling process is applied followed by an annealing process (intermediate annealing) followed by a second cold rolling process. The intermediate annealing step may be performed at a temperature of about 300°C to about 450°C (e.g., about 310°C, about 320°C, about 330°C, about 340°C, about 350°C, about 360°C, about 370°C, about 380°C, about 390°C, about 400°C, about 410°C, about 420°C, about 430°C, about 440°C, or about 450°C). In some cases, the intermediate annealing step includes multiple processes. In some non-limiting examples, the intermediate annealing step includes heating the partially 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 partially cold rolled product may be heated to about 410°C for about 1 hour, followed by heating to about 330°C for about 2 hours.

[0059] The cast, homogenized or rolled product may then optionally undergo a solution heat treatment step. The solution heat treatment step may be any suitable treatment that results in the solution of the soluble particles for the product. The cast, homogenized or rolled product may be heated to a peak metal temperature (PMT) of 590°C or less (e.g., 400°C to 590°C) and soaked at the PMT for a period of time to form a hot product. For example, the cast, homogenized or rolled product may be soaked at 480°C for a soaking time of 30 minutes or less (e.g., 0 seconds, 60 seconds, 75 seconds, 90 seconds, 5 minutes, 10 minutes, 20 minutes, 25 minutes or 30 minutes). After heating and soaking, the hot product is quenched to a temperature of 500 to 200°C at a rate of greater than 200°C / s to form a heat treated product. In one example, the hot product is cooled to a temperature of 450°C to 200°C at a quenching rate of greater than 200°C / s. Optionally, the cooling rate may be faster in other cases.

[0060] After quenching, the heat-treated product may optionally be subjected to a pre-aging treatment, for example by reheating before coiling. The pre-aging treatment may be carried out at a temperature of about 70°C to about 125°C for a period of not more than 6 hours. For example, the pre-aging treatment may be carried out at a temperature of about 70°C, about 75°C, about 80°C, about 85°C, about 90°C, about 95°C, about 100°C, about 105°C, about 110°C, about 115°C, about 120°C or about 125°C. Optionally, the pre-aging treatment may be carried out 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 carried out by passing the heat-treated product through a heating device, for example, a device that emits radiant heat, convective heat, induction heat, infrared heat, etc.

[0061] The castings described herein may be used to make products in the form of sheets, plates, or other suitable products. For example, plates, including the products described herein, may be made by processing an ingot in a homogenization step, or by casting the product in a continuous caster followed by a hot rolling step. In the hot rolling step, the castings may be hot rolled to a standard dimension of 200 mm or less (e.g., about 10 mm to about 200 mm) in thickness. For example, the castings may be hot rolled into plates having a final standard thickness dimension 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. In some cases, the plates may be rolled into thinner metal products, such as sheets.

[0062] Methods of using the aluminum alloy products of the present disclosure The aluminum alloy products described herein can be used in automotive and other transportation applications, such as aircraft and railroad applications. For example, the aluminum alloy products of the present disclosure can be used to make automotive structural components, such as bumpers, side beams, roof beams, cross beams, pillar reinforcements (e.g., A-pillars, B-pillars, and C-pillars), inner panels, outer panels, side panels, inner hoods, outer hoods, or trunk lid panels. The aluminum alloy products and methods described herein may also be used in aircraft or rail vehicle applications, for example, to make exterior and interior panels.

[0063] The aluminum alloy products and methods described herein may also be used in electronics applications. For example, the aluminum alloy products and methods described herein can be used to make housings for electronic devices, including mobile phones and tablet computers. In some examples, the aluminum alloy products can be used to make the outer frames of mobile phones (e.g., smart phones), tablet bottom frames, and housings for other portable electronic devices.

[0064] The aluminum alloy products and methods described herein may be used in any other desired application.

[0065] Methods for evaluating the characteristics of aluminum alloy products Any suitable method for determining the ratio and amount of various intermetallic particles may be used to characterize an aluminum alloy product, for example, to determine whether a particular aluminum alloy product, including a 6xxx series aluminum alloy, contains more alpha phase intermetallic particles (e.g., more by weight or mass, more in number, more by volume) than beta phase intermetallic particles. FIG. 2 outlines an example of a method for characterizing an aluminum alloy product. In block 205, an aluminum alloy product is made. Any desired technique for making an aluminum alloy product may be used, such as those described herein or in U.S. Provisional Application No. 62 / 984,675, filed March 3, 2020.

[0066] In block 210, electron microscope images of one or more portions of the aluminum alloy product may be obtained using a scanning electron microscope. For example, backscattered electron images may be obtained that may be useful for identifying various phases, grains and particles and their distribution within the aluminum alloy sample. In some cases, various images may be taken, for example, to allow for representative sampling of the aluminum alloy product.

[0067] In block 215, spatially resolved x-ray data for one or more portions of the aluminum alloy product may be obtained using a scanning electron microscope. In some cases, optionally, spatially resolved x-ray data is obtained for the same portions of the aluminum alloy product as the electron microscope image. The x-ray data may then be used to reveal the composition of the portions of the aluminum alloy product seen in the electron microscope image.

[0068] In block 220, the electron microscope image may be analyzed to identify various phases and grains within the portion of the aluminum alloy product. In some cases, different types of grains or phases in the sample may have characteristic appearances in the electron microscope image. By analyzing the electron microscope image, the number and area, volume or mass of the various phases or grains may be identified and / or estimated.

[0069] At block 225, the x-ray data may be analyzed to identify the composition of various phases and grains within the portion of the aluminum alloy product. In some cases, different types of grains or phases in a sample may exhibit characteristic x-ray signatures. By analyzing the x-ray data, the composition of the different phases or grains may be determined.

[0070] When analysis of the x-ray data and electron microscope images is complete, quantitative or qualitative information can be used to characterize and / or compare various aluminum alloy products. For example, the quantitative or qualitative information can be used to determine whether an aluminum alloy product has more alpha phase intermetallic particles than beta phase intermetallic particles, or whether one aluminum alloy product has a different distribution of alpha and beta phase intermetallic particles compared to another aluminum alloy product.

[0071] Adhesively bonded aluminum alloy products As noted above, the aluminum alloy products of the present disclosure may exhibit improved bond performance when incorporated into bonded aluminum alloy products. For example, an aluminum alloy product described herein may be adhesively bonded to another product, such as another aluminum alloy product, to form a bonded product, and the strength, longevity or durability of the bond may be desirable and may be higher than that of the comparable bonded aluminum alloy products.

[0072] FIG. 3 shows a schematic diagram of an aluminum alloy product 300 in which an aluminum alloy product 305 is bonded to a second product 310 by an adhesive 315. The second product 315 can optionally be another aluminum alloy product similar to or identical to the aluminum alloy product 305, while the second product 310 can optionally be a different aluminum alloy product or can be no aluminum alloy product. Although the aluminum alloy product 305 and the second product 310 are shown in a formed configuration in FIG. 3, one or both of the aluminum alloy product 305 and the second product 310 can optionally be in an unformed (e.g., planar) configuration. Additionally, although the adhesive 315 is shown as only partially disposed between the aluminum alloy product 305 and the second product 310 (i.e., does not cover the entire area between the aluminum alloy product 305 and the second product 310), embodiments are contemplated in which the adhesive 315 is disposed over the entire area or substantially the entire area between the aluminum alloy product 305 and the second product 310. For example, the adhesive 315 may be present in more than 60%, more than 70%, more than 80%, or more than 90% of the overlap area between the aluminum alloy product 305 and the second product 310. Examples of adhesives useful for bonding an aluminum alloy product to another product may include epoxies, acrylates, methacrylates, acrylics, adhesive tapes, polyamides, anaerobic (threadlock) adhesives, UV curable adhesives and polymers, urethanes, phenolic adhesives, sealants, silicones, acetates, etc., benzamides, enoxys, esters, oximes, or amine crosslinkable or curable silicones, polysulfides, silane modified polymers, polyethers, polyurethanes, hot melt adhesives, thermoplastic polymers, amorphous polyalphaolefins, pressure sensitive adhesives, polyamides, hot melt polyurethanes, and the like. Advantageously, the adhesive 315 may strongly bond with the surfaces of the aluminum alloy product 305 and the second product 310 and form a high strength durable joint between the aluminum alloy product 305 and the second product 310.

[0073] The intermetallic particles in the aluminum alloy product 305 may act as corrosion initiation, crack initiation or crack propagation sites. Thus, the presence of alpha and beta phase particles in the aluminum alloy product may contribute to the durability, or lack thereof, of the bond or joint between the aluminum alloy product 305 and the second product 310. For example, the beta phase particles present in the aluminum alloy product 305 may preferentially act as corrosion initiation sites. However, when beta phase particles are present in a small amount, e.g., when the weight percent ratio of alpha phase intermetallic particles to beta phase intermetallic particles in the aluminum alloy product is greater than 1, the amount or extent of corrosion may be limited such that the bond or joint between the aluminum alloy product 305 and the second product 310, the durability of the bond or joint may be improved as compared to an aluminum alloy product having a weight percent ratio of alpha phase intermetallic particles to beta phase intermetallic particles less than 1.

[0074] In some cases, the self-assembled monolayer of some phosphorus-containing organic acids may reduce the affinity for adhesion with various adhesives, such as epoxy adhesives, polyurethane adhesives, phenolic adhesives, or acrylate adhesives. For example, the self-assembled monolayer of phosphorus-containing organic acids (e.g., unsubstituted alkylphosphonic acids) that do not contain hydrophilic functional groups may provide an adhesive-resistant surface to an aluminum alloy product. In some cases, a portion of an aluminum alloy product may be pretreated, for example, to chemically modify the surface properties. For example, an aluminum alloy product may have an adhesion promoter thereon, for example, to enhance or promote the interaction between the surface of the aluminum alloy product and the adhesive. In some examples, a self-assembled monolayer of phosphorus-containing organic acids with hydrophilic functionality may impart adhesion-promoting properties to the surface of an aluminum alloy product. In some cases, a portion of an aluminum alloy product may be pretreated to have a self-assembled monolayer of phosphorus-containing organic acids with hydrophilic functionality to allow good interaction with the adhesive, while another portion of the aluminum alloy product may be pretreated to have a self-assembled monolayer of phosphorus-containing organic acids without hydrophilic functionality to allow weak or very limited interaction with the adhesive. Thus, a portion of an aluminum alloy product may have "non-stick properties," "non-adhesive properties," "anti-fouling properties," or "self-cleaning properties," which may be useful in modifying the strength of the bond between the aluminum alloy product and another product, or in providing areas of a surface with these additional characteristics. The use of phosphorus-containing organic acids that do not have hydrophilic functionality may be useful in creating surfaces with low surface energy, low surface activity, or low surface reactivity, resulting in, for example, non-stick, non-adhesive, anti-fouling, or self-cleaning properties.

[0075] Advantageously, the joined aluminum alloy product may exhibit improved bond durability between the aluminum alloy product and a second product as compared to an equivalent bond between an equivalent aluminum alloy product bonded to an equivalent second product by the same adhesive, where the equivalent aluminum alloy product has the same overall composition as the aluminum alloy product, except that the equivalent aluminum alloy product has an alpha phase stabilizing alloying element concentration of less than 0.5 wt.% and a weight percent ratio of alpha phase intermetallic compound particles to beta phase intermetallic compound particles of less than 1. For example, the equivalent aluminum alloy product may correspond to an aluminum alloy product in which the ratio or concentration of alpha phase intermetallic compound particles to beta phase intermetallic compound particles has not been treated to convert the beta phase intermetallic compound particles to alpha phase intermetallic compound particles to beta phase intermetallic compound particles, resulting in a greater amount of beta phase intermetallic compound particles compared to the alpha phase intermetallic compound particles.

[0076] The following examples will serve to further illustrate the present invention, but at the same time, do not constitute any limitation to the present invention.On the contrary, it should be clearly understood that various embodiments, modifications and equivalents thereof that would be naturally suggested to a person skilled in the art after reading the description of this specification can be utilized without departing from the spirit of the present invention.Unless otherwise indicated, conventional procedures were followed during the studies described in the following examples.Some of the procedures are described below for illustrative purposes. EXAMPLES

[0077] Example 1 To evaluate the ability of the alpha stabilizing elements to modify the ratio of alpha to beta intermetallic particles, three different AA6451 aluminum alloys were prepared. One alloy was a control alloy in which the concentrations of chromium and manganese in the alloy were limited to trace levels, one test alloy contained additional manganese at a concentration of 0.13 wt.%, and one test alloy contained additional manganese and chromium at concentrations of 0.13 wt.% Mn and 0.06 wt.% Cr. Samples of each alloy were subjected to various homogenization conditions and the phase distribution of alpha to beta intermetallic particles by area was determined to reveal the ratio of the amount of alpha to beta intermetallic particles in each sample. The results are summarized in Table 1. [Table 1]

[0078] Example 2 Eight specimens of rolled sheet metal of two different AA6451 aluminum alloys were prepared to evaluate the ability of the alpha stabilizing elements to modify the joining performance of the alloy. One alloy was a control alloy in which the concentrations of chromium and manganese in the alloy were limited to trace levels, and one alloy was a test alloy containing 0.08 wt.% and 0.13 wt.% additional chromium and manganese, respectively. The control and test alloy specimens were processed according to a first cast, homogenize and roll condition (process condition 1) with a coiling / recoiling temperature above the recrystallization temperature of the alloy, and the control and test alloy specimens were processed according to a second cast, homogenize and roll condition (process condition 2) with a coiling / recoiling temperature below the recrystallization temperature of the alloy.

[0079] The replicated samples were subjected to bond durability testing. For example, this may be performed according to the procedure of ASTM D3762-03 (2010), Standard Test Method for Adhesive-Bonded Surface Durability of Aluminum (Wedge Test) (Withdrawn 2019), ASTM International, West Conshohocken, PA, 2010, which is incorporated herein by reference. In another example, FLTM BV 101-07 standard test, Stress Durability Test for Adhesive Lap-Sear Bonds (2017), which is incorporated herein by reference, may be used. For these tests, pairs of rolled sheet metal samples are adhesively bonded together using epoxy at six bond sites. Each bonded pair is then subjected to various test conditions. For example, the test conditions may include one or more of immersion in a salt solution, exposure to humid conditions, exposure to dry conditions, or application of forces including stress or strain. Each bonded pair is subjected to multiple cycles of these test conditions. Typically, each bonded pair is subjected to a sufficient number of cycles to result in bond failure. In some cases, a maximum number of cycles is used, e.g., 35, 45 or 60 cycles. The results of bond durability testing under two different test conditions are shown in Tables 2 and 3. The results generally showed improved bond durability in the alloy samples containing additional manganese and chromium compared to the control alloy. [Table 2] [Table 3]

[0080] Exemplary embodiments As used hereinafter, any reference to a series of embodiments, including a reference to a group of embodiments (e.g., "any preceding or subsequent embodiment"), should be understood to be a reference to each of those embodiments separately (e.g., "Embodiments 1-4" should be understood to be "Embodiments 1, 2, 3 or 4").

[0081]

[0023] Aspect 1 is an aluminum alloy product comprising a 6xxx series aluminum alloy, wherein a total concentration of alpha phase stabilizing alloying elements in the 6xxx series aluminum alloy is about 0.2 wt.% or greater, or a ratio of the total concentration of the alpha phase stabilizing alloying elements to an amount of excess silicon in the 6xxx series aluminum alloy is about 1.0 or greater, or a ratio of the amount of magnesium in the 6xxx series aluminum alloy to the amount of silicon in the 6xxx series aluminum alloy is about 4.0 or less; the 6xxx series aluminum alloy comprises beta phase intermetallic compound grains and alpha phase intermetallic compound grains; and further, a weight percent ratio of the alpha phase intermetallic compound grains to the beta phase intermetallic compound grains in the aluminum alloy product is greater than 2.0.

[0082] Aspect 2 is an aluminum alloy product according to any preceding or following aspect, exhibiting a bond durability of 30 to 65 cycles or more according to the ASTM D3762 standard test or the FLTM BV 101-07 standard test.

[0083] Example 3 is the aluminum alloy product of any preceding or following example, wherein the 6xxx series aluminum alloy comprises 0.25 wt.% or less titanium carbide.

[0084] Example 4 is the aluminum alloy product of any preceding or following example, wherein the alpha phase stabilizing alloying elements include one or more of copper, chromium, manganese, zirconium, or vanadium.

[0085] Example 5 is the aluminum alloy product of any preceding or following example, wherein the total concentration of the alpha phase stabilizing alloying elements is less than or equal to about 2 wt.%.

[0086] Example 6 is the aluminum alloy product of any preceding or following example, wherein the ratio of the total concentration of the alpha phase stabilizing alloying elements to the amount of excess silicon in the 6xxx series aluminum alloy is less than or equal to about 3.

[0087]

[0023] Aspect 7 is the aluminum alloy product of any preceding or following aspect, wherein the 6xxx series aluminum alloy comprises up to 1.8 wt.% silicon, up to 1.8 wt.% iron, up to 1.5 wt.% copper, up to 0.5 wt.% manganese, 0.2 wt.%-3.0 wt.% magnesium, up to 0.25 wt.% titanium, up to 1.5 wt.% zinc, up to 1 wt.% nickel, up to 0.25 wt.% vanadium, up to 0.25 wt.% zirconium, up to 0.5 wt.% chromium, and aluminum.

[0088] Example 8 is the aluminum alloy product of any preceding or following example embodiment, further comprising up to 0.15 wt.% impurities, the balance of the 6xxx series aluminum alloy comprising aluminum.

[0089] Example 9 is the aluminum alloy product of any preceding or following example, wherein the amount of excess silicon in the 6xxx series aluminum alloy is about 0.1 wt.% or greater.

[0090] Example 10 is the aluminum alloy product of any preceding or following example, wherein the amount of excess silicon in the 6xxx series aluminum alloy is about 1.4 wt.% or less.

[0091] Example 11 is the aluminum alloy product of any preceding or following example, wherein the 6xxx series aluminum alloy is substantially free of boron.

[0092] Example 12 is the aluminum alloy product of any preceding or following example, wherein the parts per million concentration of carbide grain refiner in the 6xxx series aluminum alloy is 10 or less.

[0093] Example 13 is the aluminum alloy product of any preceding or following example, wherein the ratio of the combined concentration of alpha phase stabilizing elements to iron in the alpha phase intermetallic particles is greater than 0.5.

[0094] Example 14 is the aluminum alloy product of any preceding or following example, wherein the β-phase intermetallic grains exhibit an aspect ratio greater than 2 and the α-phase intermetallic grains exhibit an aspect ratio between 1 and 1.5.

[0095] Example 15 is the aluminum alloy product of any preceding or following example, wherein the β phase intermetallic particles comprise aluminum, iron, and silicon; and the α phase intermetallic particles comprise aluminum, silicon, and one or more of iron, manganese, or chromium.

[0096] Example 16 is the aluminum alloy product of any preceding or subsequent example, wherein the weight percentage ratio of the α phase intermetallic grains to the β phase intermetallic grains in the aluminum alloy product is determined by a process that includes phase characterization using Energy Dispersive X-ray Spectroscopy (EDXS) compositional analysis.

[0097] Example 17 is the aluminum alloy product of any preceding or following example, wherein the β-phase intermetallic particles have a corrosion potential greater than a corrosion potential of an aluminum alloy matrix bearing the β-phase intermetallic particles.

[0098] Example 18 is the aluminum alloy product of any preceding or following example, wherein the corrosion potential of the β phase intermetallic particles is greater than the corrosion potential of the α phase intermetallic particles.

[0099] Example 19 is the aluminum alloy product of any preceding or following example, wherein the aluminum alloy product exhibits a reduced corrosion potential relative to a comparable aluminum alloy product, the comparable aluminum alloy product comprising a comparable 6xxx series aluminum alloy having a combined concentration of alpha phase stabilizing alloying elements less than 0.5 wt.%, beta phase intermetallic compound particles, and alpha phase intermetallic compound particles, wherein an equivalent weight percent ratio of the alpha phase intermetallic compound particles to the beta phase intermetallic compound particles in the comparable aluminum alloy is less than 1.

[0100] Example 20 is a bonded aluminum alloy product comprising an aluminum alloy product as described in any preceding or following example, a second product, and an adhesive between the aluminum alloy product and the second product, the adhesive bonding the aluminum alloy product and the second product.

[0101]

[0023] Example 21 is a joined aluminum alloy product according to any preceding or following example, exhibiting a joint durability of 30 to 65 cycles or more according to the ASTM D3762 standard test or the FLTM BV 101-07 standard test.

[0102] Example 22 is the joined aluminum alloy product of any preceding or following example, further comprising an adhesion promoter on a surface of the aluminum alloy product or between the aluminum alloy product and the adhesive.

[0103] Example 23 is the joined aluminum alloy product of any preceding or following example, wherein at least a portion of a surface of the aluminum alloy product is chemically modified or pretreated.

[0104] Example 24 is the joined aluminum alloy product of any preceding or following example, wherein at least a portion of a surface of the aluminum alloy product comprises a self-assembled monolayer of one or more phosphorus-containing organic acids.

[0105] Example 25 is a method, comprising: making an aluminum alloy product, the aluminum alloy product comprising a 6xxx series aluminum alloy, wherein a total concentration of alpha phase stabilizing alloying elements in the 6xxx series aluminum alloy is about 0.2 wt.% or greater, or a ratio of the total concentration of the alpha phase stabilizing alloying elements to an amount of excess silicon in the 6xxx series aluminum alloy is about 1.0 or greater, or a ratio of the amount of magnesium in the 6xxx series aluminum alloy to the amount of silicon in the 6xxx series aluminum alloy is about 4.0 or less; beta phase intermetallic compound particles; and alpha phase intermetallic compound particles; and further comprising subjecting the aluminum alloy product to processing conditions that modify or control a weight percent ratio of the alpha phase intermetallic compound particles to the beta phase intermetallic compound particles in the aluminum alloy product to be greater than 2.

[0106] Example 26 is the method of any preceding example, wherein the subjecting produces the aluminum alloy product of any preceding example.

[0107] Example 27 is the aluminum alloy product of any preceding embodiment, made according to the method of any preceding embodiment.

[0108] All patents, publications and abstracts cited above are hereby incorporated by reference in their entirety. The above description of the embodiments, including the illustrated embodiment, has been presented merely for purposes of illustration and description and is not intended to be exhaustive or limited to the precise form disclosed. Numerous modifications, adaptations and uses thereof will be apparent to those skilled in the art.

Claims

1. An aluminum alloy product, 6xxx series aluminum alloy wherein the total concentration of alpha phase stabilizing alloying elements in the 6xxx series aluminum alloy is about 0.2 wt.% or greater, or the ratio of the total concentration of the alpha phase stabilizing alloying elements to the amount of excess silicon in the 6xxx series aluminum alloy is about 1.0 or greater, or the ratio of the amount of magnesium in the 6xxx series aluminum alloy to the amount of silicon in the 6xxx series aluminum alloy is about 4.0 or less; the 6xxx series aluminum alloy comprises β-phase intermetallic compound grains and α-phase intermetallic compound grains; and a weight percentage ratio of the alpha phase intermetallic grains to the beta phase intermetallic grains in the aluminum alloy product is greater than 2.0; The aluminum alloy product.

2. 2. The aluminum alloy product according to claim 1, exhibiting a bond durability of 30 to 65 cycles or more according to ASTM D3762 standard test or FLTM BV 101-07 standard test.

3. 2. The aluminum alloy product of claim 1, wherein the 6xxx series aluminum alloy contains up to 0.25 wt.% titanium carbide.

4. 2. The aluminum alloy product of claim 1, wherein the alpha phase stabilizing alloying elements include one or more of copper, chromium, manganese, zirconium, or vanadium.

5. 2. The aluminum alloy product of claim 1, wherein the total concentration of said alpha phase stabilizing alloying elements is less than or equal to about 2 wt.%.

6. 2. The aluminum alloy product of claim 1, wherein a ratio of the total concentration of said alpha phase stabilizing alloying elements to the amount of said excess silicon in said 6xxx series aluminum alloy is less than or equal to about 3.

7. The 6xxx-series aluminum alloy is 1.8 wt. % or less silicon; 1.8 wt. % or less of iron; % copper or less; 0.5 wt. % or less of manganese; 0.2 wt. % to 3.0 wt. % magnesium; 0.25 wt. % or less of titanium; % zinc or less; 1 wt. % or less of nickel; 0.25 wt. % or less of vanadium; 0.25 wt. % or less of zirconium; 0.5 wt. % or less of chromium, and aluminum 2. The aluminum alloy product of claim 1, comprising:

8. 8. The aluminum alloy product of claim 7, further comprising up to 0.15 wt.% impurities, the balance of the 6xxx series aluminum alloy comprising aluminum.

9. 2. The aluminum alloy product of claim 1, wherein the amount of excess silicon in the 6xxx series aluminum alloy is greater than or equal to about 0.1 wt.%.

10. 2. The aluminum alloy product of claim 1, wherein the amount of excess silicon in the 6xxx series aluminum alloy is less than or equal to about 1.4 wt.%.

11. 2. The aluminum alloy product of claim 1, wherein the 6xxx series aluminum alloy is substantially free of boron.

12. 2. The aluminum alloy product of claim 1, wherein the parts per million concentration of carbide grain refiner in the 6xxx series aluminum alloy is less than or equal to 10.

13. 2. The aluminum alloy product of claim 1, wherein the ratio of the combined concentration of said alpha phase stabilizing elements to iron in said alpha phase intermetallic grains is greater than 0.

5.

14. the β-phase intermetallic grains exhibit an aspect ratio greater than 2; the α-phase intermetallic compound particles exhibit an aspect ratio of 1 to 1.5; 2. The aluminum alloy product of claim 1.

15. the β-phase intermetallic particles include aluminum, iron and silicon; The α-phase intermetallic compound particles are aluminum, Silicon, and One or more of iron, manganese, or chromium 2. The aluminum alloy product of claim 1, comprising:

16. the weight percentage ratio of the alpha phase intermetallic grains to the beta phase intermetallic grains in the aluminum alloy product being: Phase characterization using energy dispersive x-ray spectroscopy (EDXS) compositional analysis 2. The aluminum alloy product of claim 1, wherein the aluminum alloy product is determined by a process comprising:

17. 2. The aluminum alloy product of claim 1, wherein the corrosion potential of the β-phase intermetallic particles is greater than the corrosion potential of the aluminum alloy matrix carrying the β-phase intermetallic particles.

18. 2. The aluminum alloy product of claim 1, wherein the corrosion potential of the β-phase intermetallic particles is greater than the corrosion potential of the α-phase intermetallic particles.

19. the aluminum alloy product exhibits a reduced corrosion potential compared to a comparable aluminum alloy product; Said equivalent aluminum alloy product is an equivalent 6xxx series aluminum alloy having a total concentration of alpha-phase stabilizing alloying elements less than 0.5 wt. %; β-phase intermetallic particles and α phase intermetallic compound particles wherein the equivalent weight percent ratio of the alpha phase intermetallic particles to the beta phase intermetallic particles in the equivalent aluminum alloy is less than 1.

2. The aluminum alloy product of claim 1.

20. A bonded aluminum alloy product comprising: The aluminum alloy product according to any one of claims 1 to 19. The second product, and an adhesive between the aluminum alloy product and the second product; wherein the adhesive bonds the aluminum alloy product and the second product.

21. 21. The bonded aluminum alloy product of claim 20, exhibiting a bond durability of 30 to 65 cycles or more according to ASTM D3762 standard test or FLTM BV 101-07 standard test.

22. 21. The bonded aluminum alloy product of claim 20, further comprising an adhesion promoter on a surface of the aluminum alloy product or between the aluminum alloy product and the adhesive.

23. 21. The bonded aluminium alloy product of claim 20, wherein at least a portion of a surface of the aluminium alloy product is chemically modified or pretreated.

24. At least a portion of the surface of the aluminum alloy product is One or more phosphorus-containing organic acids 21. The bonded aluminium alloy product of claim 20 comprising a self-assembled monolayer of:

25. 1. A method comprising: Manufacturing aluminum alloy products The aluminum alloy product comprises: 6xxx series aluminum alloy wherein the total concentration of alpha phase stabilizing alloying elements in said 6xxx series aluminum alloy is about 0.2 wt.% or greater, or the ratio of the total concentration of said alpha phase stabilizing alloying elements to the amount of excess silicon in said 6xxx series aluminum alloy is about 1.0 or greater, or the ratio of the amount of magnesium in said 6xxx series aluminum alloy to the amount of silicon in said 6xxx series aluminum alloy is about 4.0 or less; β-phase intermetallic particles; and α phase intermetallic compound particles and subjecting said aluminum alloy product to processing conditions that modify or control a weight percentage ratio of said alpha phase intermetallic compound particles to said beta phase intermetallic compound particles in said aluminum alloy product to greater than 2. The method comprising:

26. 26. A method according to claim 25, wherein said subjecting produces an aluminium alloy product according to any of claims 1 to 19.

27. 26. An aluminium alloy product according to any preceding claim, produced according to the method of claim 25.

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