WO2015169232A1

WO2015169232A1 - Aluminum alloy and method of prepairing the same

Info

Publication number: WO2015169232A1
Application number: PCT/CN2015/078408
Authority: WO
Inventors: Faliang Zhang; Yongxi Jian; Shaoqing LI; Qing Gong
Original assignee: Byd Company Limited
Priority date: 2014-05-08
Filing date: 2015-05-06
Publication date: 2015-11-12
Also published as: CN105088019A

Abstract

An aluminum alloy contains 1-4wt％ of Mn, 0.1-5wt％ of Mg, 0.002-0.5wt％ of a rare earth element, 0-2wt％ of Co, 0-1.5wt％ of Fe, 0-1wt％ of Ti, 0-1wt％ of Cu, 0-1.6wt％ of Zn, 0-0.5wt％ of Si, and 82.9-98.898wt％ of Al, based on total weight of the aluminum alloy. The rare earth element contains La. Based on the total weight of the rare earth element, the content of La in the rare earth element is from 20wt％ to 100wt％. A method of preparing an aluminum alloy, a method of coloring a surface of an aluminum alloy and an aluminum alloy product are also provided.

Description

ALUMINUM ALLOY AND METHOD OF PREPAIRING THE SAME

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and benefits of Chinese Patent Application No. 201410193182.9, filed with the State Intellectual Property Office of P.R. China on May 8, 2014, the entire content of which is incorporated herein by reference.

FIELD

The present disclosure relates aluminum alloys, and more particularly relates to an aluminum alloy, a method of preparing an aluminum alloy, a method of coloring an aluminum alloy, and an aluminum alloy product.

BACKGROUND

Aluminum alloys have been widely applied due to some advantages such as light weight, rich in resources and being easily colored. The aluminum alloy is mainly divided into deformed aluminum alloys and casting aluminum alloys, in which the casting aluminum alloy may be further divided into Al-Si series, Al-Mg series, Al-Si-Cu series and Al-Zn series according to different material seriess.

As a casting aluminum alloy, the Al-Si series aluminum alloy has been most widely applied due to a good casting performance and a good overall performance. However, after being anodized, Al-Si series aluminum alloy may have an obvious chromatic aberration, such as becoming gray or black, thus being hard to be applied in various metalloid products, especially consumer electronics. Al-Mg series aluminum alloy is good for anodizing, but it has a relative higher Mg content, which may easily absorb gases and produce slags during smelting and casting processes, and therefore a property of the aluminum alloy product may be uncontrolled. Al-Zn series aluminum alloy has an excellent mechanical strength, but it has a poor casting fluidity accompanied with a trend of thermo crack. Further, the Al-Zn series aluminum alloy is hard to be colored by anodizing.

At present, an aluminum alloy workpiece applied in consumer electronics is mainly manufactured by machining or forging, which may be high in cost. Therefore, a casting product of an aluminum alloy which is acceptable to anodizing is necessary.

SUMMARY

Embodiments of the present disclosure seek to solve at least one of the problems existing in the prior art to at least some extent, particularly a technical problem that an aluminum alloy does not have good anodizing performance and good casting performance simultaneously. Accordingly, an aluminum alloy and a method of preparing the same are provided. According to the present disclosure, the aluminum alloy may be used for die casting and anodizing, and a casting product of the aluminum alloy may have excellent comprehensive mechanic performances.

According to a first aspect of the present disclosure, an aluminum alloy is provided. Based on the total weight of the aluminum alloy, the aluminum alloy includes: 1-4wt％of Mn； 0.1-5wt％of Mg； 0.002-0.5wt％of a rare earth element, the rare earth element including La, and based on the total weight of the rare earth element, the content of La in the rare earth element ranging from 20wt％to 100wt％； 0-2wt％of Co； 0-1.5wt％of Fe； 0-1wt％of Ti； 0-1wt％of Cu； 0-1.6wt％of Zn； 0-0.5wt％of Si； and 82.9-98.898wt％of Al.

According to a second aspect of the present disclosure, an aluminum alloy is provided. Based on the total weight of the aluminum alloy, the aluminum alloy includes: 1-4wt％of Mn； 0.1-5wt％of Mg； 0.002-0.5wt％of a rare earth element, the rare earth element including La, and based on the total weight of the rare earth element, the content of La in the rare earth element ranging from 20wt％to 100wt％； 0-2wt％of Co； 0-1.5wt％of Fe； 0-1wt％of Ti； 0-1wt％of Cu； 0-1.6wt％of Zn； 0-0.5wt％of Si； and a balance of Al.

According to a third aspect of the present disclosure, a method of preparing an aluminum alloy is provided. And the method of preparing an aluminum alloy includes the steps of: smelting and cooling a raw material of the aluminum alloy, in which a composition of the raw material of the aluminum alloy is suitable for forming the above-identified aluminum alloy according to the first or second aspect of the present disclosure.

According to a fourth aspect of the present disclosure, a method of coloring a surface of an aluminum alloy is provided. And the method of coloring a surface of an aluminum alloy includes the steps of: anodizing at least a part of a surface of an aluminum alloy substrate to form an oxide film layer on the surface, and coloring the oxide film layer, in which the aluminum alloy substrate is a die casting of the above-identified aluminum alloy according to the first or second aspect of the present disclosure.

According to a fifth aspect of the present disclosure, an aluminum alloy product is provided. And the aluminum alloy product includes: an aluminum alloy substrate； and an oxide film layer formed on at least a part of a surface of the aluminum alloy substrate, in which the aluminum alloy substrate is a die casting of the aluminum alloy according to the first or second aspect of the present disclosure.

According to some embodiments of the present disclosure, the aluminum alloy may be used to form die casting. The obtained die casting of the aluminum alloy may have not only a relative higher overall performance, but also a good anodic oxidation characteristic and a good coloring characteristic, i.e. the aluminum alloy may be easily anodized and colored. Therefore, the aluminum alloy and the die casting may be especially suitable for products that have a relative higher requirement on appearance.

Additional aspects and advantages of embodiments of present disclosure will be given in part in the following descriptions, become apparent in part from the following descriptions, or be learned from the practice of the embodiments of the present disclosure.

DETAILED DESCRIPTION

Reference will be made in detail to embodiments of the present disclosure. The embodiments described herein are explanatory, illustrative, and used to generally understand the present disclosure. The embodiments shall not be construed to limit the present disclosure.

According to a first aspect of the present disclosure, an aluminum alloy is provided. Based on the total weight of the aluminum alloy, the aluminum alloy includes: 1-4wt％of Mn； 0.1-5wt％of Mg； 0.002-0.5wt％of a rare earth element； 0-2wt％of Co； 0-1.5wt％of Fe； 0-1wt％of Ti； 0-1wt％of Cu； 0-1.6wt％of Zn； 0-0.5wt％of Si； and 82.9-98.898wt％of Al. The rare earth element contains La, and based on the total weight of the rare earth element, the content of La in the rare earth element ranges from 20wt％to 100wt％.

In some embodiments of the present disclosure, Mn may react with the element Al to form MnAl6 to improve a solid solution strengthening effect, thus enhancing mechanical strength of the aluminum alloy. The increase of the mechanical strength may not only make the aluminum alloy meet the strength requirement as a structural member, but also improve a demoulding performance of a casting of the aluminum alloy, thus ensuring a casting precision of products. However, if the content of Mn in the aluminum alloy is too low, there may be no contribution in improvements on solid solution. In contrast, if the content of Mn in the aluminum alloy exceeds 4wt％, the anodizing performance of the aluminum alloy may be affected seriously, which leads to unfavorable obvious color spots on a casting product of the aluminum alloy. In some embodiments of the present disclosure, the content of Mn in the aluminum alloy ranges from 1wt％to 4wt％, based on the total weight of the aluminum alloy. With this content, a solid solution strengthening effect may be ensured without affecting the anodizing performance of the aluminum alloy. In some embodiments, based on the total weight of aluminum alloy, the content of Mn in the aluminum alloy ranges from 1wt％to 3 wt％, alternatively 1wt％to 2.5wt％. With these contents, the anodizing performance of the aluminum alloy may be further improved.

In some embodiments of the present disclosure, a reaction between Mg and Mn may improve not only the solid solution strengthening effect but also corrosion resistance of the aluminum alloy. Under a condition of solid state, Mg may be completely dissolved in single-phase α solid solution and may not be easily electrochemically corroded in a corrosive medium； and even though a little Al8Mg5 anode phase may be generated, Mg may remain in the single-phase α solid solution after the anode phase is corroded. If the content of Mg in the aluminum alloy is too high, pores in the oxide film layer may be more and some black spots may be generated if an anodic oxidation is performed. In some embodiments of the present disclosure, the content of Mg in the aluminum alloy ranges from 0.1wt％to 5wt％, based on the total weight of the aluminum alloy. With this content, the corrosion resistance of the aluminum alloy may be significantly improved, without producing too many pores during the anodic oxidation process. In some embodiments of the present disclosure, based on the total weight of the aluminum alloy, the content of Mg in the aluminum alloy ranges from 0.1wt％to 1wt％. With this content, the aluminum alloy may obtain a good anodic oxidation performance. In some embodiments of the present disclosure, based on the total weight of the aluminum alloy, the content of Mg in the aluminum alloy ranges from 3wt％to 5wt％. With this content, the aluminum alloy has both a relative better anodic oxidation effect and a good comprehensive mechanical performance.

In some embodiments of the present disclosure, the aluminum alloy includes a rare earth element, and the rare earth element includes La, thus not only significantly improving the metallurgical property and fluidity of aluminum alloy, but also ensuring a relative better anodic oxidation performance, which further ensures the aluminum alloy is capable of forming an oxide film layer with a relative high quality. However, an excessive rare earth element may not only reduce a mechanical strength of the aluminum alloy, but also weaken anodic oxidation performance of the aluminum alloy, i.e. causing some black spots in the oxide film layer during the anodizing process. In some embodiments of the present disclosure, based on the total weight of the present disclosure, the content of the rare earth element in the aluminum alloy is 0.002wt％-0.5wt％, alternatively 0.01wt％-0.5wt％, further alternatively 0.01wt％-0.2wt％, such as 0.05wt％-0.2wt％.

In some embodiments of the present disclosure, based on the total weight of the rare earth element, the content of La in the rare earth element ranges from 20wt％to 100wt％, i.e., in some embodiments of the present disclosure, the rare earth element includes La and some other rare earth elements. In an embodiment of the present disclosure, based on the total weight of the rare earth element, the content of La in the rare earth element exceeds 40wt％. With this content, an oxide film layer with a relative higher quality may be obtained. In some embodiments of the present disclosure, the rare earth element further has other rare earth elements, such as Ce. In some embodiments of the present disclosure, the rare earth element includes La and Ce, and based on the total weight of the rare earth element, the content of La in the rare earth element is 20wt％-99wt％, alternatively 40wt％-90wt％； and the content of Ce in the rare earth element is 1wt％-80wt％, alternatively 10wt％-60wt％.

In some embodiments of the present disclosure, the aluminum alloy further includes Co. Co has a relative lower solubility in the aluminum alloy, but Co may react with Al to form AlCo to be distributed in the alloy substrate, which may refine grains, and improve the mechanical strength and an oxidation coloring property of aluminum alloy. However, if the content of Co in the aluminum alloy is too large, some hard spots may be generated in the oxide film layer, causing it difficult to obtain a uniform oxide film layer. In contrast, if the content of Co in the aluminum alloy is not larger than 2wt％, the anodic oxidation performance of the aluminum alloy may not be affected. In some embodiments of the present disclosure, based on the total weight of the aluminum alloy, the content of Co in the aluminum alloy is 0-2wt％, alternatively 0.1wt％-2wt％, such as 0.5wt％-2wt％.

In some embodiments of the present disclosure, the aluminum alloy further includes Fe. In some embodiments of the present disclosure, due to the presence of Mn element, Mn, Fe and Al elements may react with each other to form a precipitate phase together, thus eliminating the influence brought by Fe element. In addition, it improves a mechanical performance of the aluminum alloy and reduces a viscidity of the aluminum alloy. However, if the content of Fe in the aluminum alloy is too large, some hard spots may generate in the oxide film layer, causing it difficult to obtain a uniform oxide film layer. In some embodiments of the present disclosure, based on the total weight of the aluminum alloy, the content of Fe in the aluminum alloy is 0-1.5wt％, alternatively 0.5wt％-1.5wt％. With these contents, the aluminum alloy may not only has a good mechanical property but also a relative good anodic oxidation performance.

In some embodiments of the present disclosure, the aluminum alloy includes Ti. Ti acts as a grain refining agent to effectively modify a brittleness of the aluminum alloy and improve the malleability of the aluminum alloy. In some embodiments of the present disclosure, based on the total weight of aluminum alloy, the content of Ti in the aluminum alloy is 0-1wt％, alternatively 0.1-1wt％. With these contents, both the relative good anodic oxidation performance and the good malleability of the aluminum alloy are ensured.

In one embodiment of the present disclosure, the aluminum alloy includes at least one element selected from a group consisted of Co, Fe and Ti, and based on the total weight of the aluminum alloy, the contents of the above elements are as follow: 0.1wt％-2wt％of Co, 0.5wt％-1.5wt％of Fe, and 0.1wt％-1wt％of Ti.

The Applicants found that, although Cu, Si and Zn may improve a mechanical performance and a casting performance of the aluminum alloy, these elements may reduce a corrosion resistance of the aluminum alloy and affect the oxidation coloring performance. In some embodiments of the present disclosure, based on the total weight of the aluminum alloy, the content of Cu in the aluminum alloy is 0-1wt％ (such as 0-0.8wt％) , the content of Si in the aluminum alloy is 0-0.5wt％ (such as 0-0.3wt％) , and the content of Zn in the aluminum alloy is 0-1.6wt％ (such as 0-1wt％) . With these elements and contents thereof, the corrosion resistance and oxidation coloring performances of the aluminum alloy may be ensured, without influencing the mechanical performance and the casting performance of the aluminum alloy.

In some embodiments of the present disclosure, the aluminum alloy may further include a small quantity of other metal elements, such as Li, Na, K, Be, Ca, Sr, Ba, Ga, In, Ge, Sn, Sb, Bi, Sc, Y, Zr, V, Nb, Cr, Mo, W, Tc, Ru, Ni, Pd, Pt, Ag, Au and at least one rare earth element except La and Ce. In some embodiments of the present disclosure, based on the total weight of the aluminum alloy, the total weight of the above other metal elements may be equal to or less than 1wt％, alternatively equal to or less than 0.5wt％, further alternatively equal to or less than 0.2wt％. In some embodiments of the present disclosure, the above other metal elements may be from unavoidable impurities in a raw material of the aluminum alloy, or from an element added as a raw material of the aluminum alloy.

In some embodiments of the present disclosure, the content of Al in the aluminum alloy may be adjusted according to the total weight of the aluminum alloy.

In one embodiment of the present disclosure, based on the total weight of the aluminum alloy, the aluminum alloy includes: 1-4wt％of Mn； 0.1-5wt％of Mg； 0.002-0.5wt％of a rare earth element； 0-2wt％of Co； 0-1.5wt％of Fe； 0-1wt％of Ti； 0-1wt％of Cu； 0-1.6wt％of Zn； 0-0.5wt％of Si； and a balance of Al. The rare earth element has La, and based on the total weight of the rare earth element, the content of La in the rare earth element ranges from 20wt％to 100wt％. In the above embodiment of the present disclosure, the aluminum alloy may have other metal elements or not.

The aluminum alloy according to the present embodiment may be prepared by various methods. In some embodiments, a method of preparing an aluminum alloy includes the steps of: smelting and cooling a raw material of the aluminum alloy, in which, the composition of the raw material of the aluminum alloy is suitable for forming an aluminum alloy according to the present disclosure.

In some embodiments of the present disclosure, the aluminum alloy may be molded by casting to form a die casting with required shapes, a good overall mechanical performance and a good anodic oxidation performance, which facilitates to form an oxide film layer with a good quality and without defects, like black spots, pores or hard spots.

In some embodiments of the present disclosure, a method of coloring a surface of an aluminum alloy is provided. The method includes the steps of: anodizing a surface of an aluminum alloy substrate to form an oxide film layer on at least a part of the surface, and coloring the oxide film layer, in which, the aluminum alloy substrate is a die casting of the aluminum alloy according to embodiments of the present disclosure. The composition of the aluminum alloy and the method of preparing the same are described above, and thus the detailed description thereof is omitted herein for brevity.

A molded product may be obtained by smelting and casting a raw material of the aluminum alloy with a conventional method in the art.

There’s no special limitation to the methods of forming an oxide film layer on the aluminum alloy, which may be a conventional method. In one embodiment of the present disclosure, under an anodic oxidation condition, an aluminum alloy substrate is placed in electrolyte, the aluminum alloy substrate is used as an anode, a conductive material which may not react with the electrolyte is used as a cathode, the anode and the cathode are electrically connected with the negative electrode and the positive electrode of a power respectively, after turning on the power, an oxide film layer may be formed on the aluminum alloy substrate.

There’s no special limitation to the electrolyte, which may be any conventional electrolyte. In some embodiments, the electrolyte may be an electrolyte containing at least one of sulfuric acid, chromic acid and oxalic acid.

There’s no special limitation to the conditions of the anodic oxidation, which may be conventional conditions. For example, in the process of anodic oxidation, a voltage applied on the positive electrode and the negative electrode may be 10-30 V, and the anodic oxidation may be performed at a temperature of 20-70℃for 10-120min.

There‘s no special limitation to the method for coloring the oxide film layer, which may be any conventional methods in the art. In one embodiment of the present disclosure, a method of coloring a surface of an aluminum alloy includes the steps of: immersing an anodized aluminum alloy substrate into a coloring agent solution to color an oxide film layer of the anodized aluminum alloy substrate, in which the aluminum alloy substrate is a die casting of the aluminum alloy of embodiments of the present disclosure. In another embodiment of the present disclosure, the electrolyte for anodic oxidation further contains a coloring agent, and the oxide film layer may be formed and colored at the same time, i.e. the oxide film layer is colored during the anodic oxidation process. There are no special limits to the content of the coloring agent in the electrolyte, provided the oxide film layer is colored without affecting the process of anodic oxidation.

In some embodiments of the present disclosure, the method of coloring a surface of an aluminum alloy further includes sealing pores in an outer surface of the oxide film layer after coloring the oxide film layer. With the sealing step, the oxide film layer may obtain improved surface hardness, better abrasion resistance and better corrosion resistance. There are no special limitations to the method of sealing pores in an outer surface of the oxide film layer, which may be any conventional methods of pore sealing, such as hot sealing (i.e., boiling water sealing) , cold sealing, organics sealing and moderate temperature sealing.

In some embodiments of the present disclosure, an aluminum alloy product is provided. The aluminum alloy product includes an aluminum alloy substrate； and an oxide film layer formed on a surface of the aluminum alloy substrate； in which, the aluminum alloy substrate is a die casting of the aluminum alloy of embodiments of the present disclosure.

There are no special limitations to the thickness of the oxide film layer, which may be conventional. For example, the oxide film layer has a thickness of about 10 μm to about 200 μm.

According to the aluminum alloy product of the present disclosure, the oxide film layer may be a colored oxide film layer. In this way, the oxide film layer may have colors, and therefore the aluminum alloy product of the present disclosure may be present in different colors. The color of the oxide film layer may be selected according to usage requirements, thus meeting usage requirements.

The present disclosure will be described below in detail with reference to examples, which are provided for example only and will not be construed as limitations to the present disclosure.

In the following Examples and Comparative Examples, surface hardness of the aluminum alloy is tested according to GBT 4340 1-2009； tensile strength of the aluminum alloy is tested according ISO 6892-1: 2009.

In the following Examples and Comparative Examples, the anodic oxidation effect and the coloring effect are evaluated with following standards.

Perfect: the oxide film layer has no spots or hard spots and can be colored with any colors； the colored oxide film layer has a uniform color without chromatic aberrations or stains.

Excellent: the oxide film layer has no spots or hard spots and can be colored with any colors； the colored oxide film layer has a uniform color without obvious stains.

General: the oxide film layer has no spots or hard spots and can be colored with some colors； the colored oxide film layer has a substantially uniform color without obvious stains.

Poor: the oxide film layer has no spots and/or hard spots and can be colored with a few colors； the colored oxide film layer has a nonuniform color and obvious stains.

Example 1

In this example, an aluminum alloy and an aluminum alloy product were prepared.

1) Preparation of aluminum alloy

Raw materials of an aluminum alloy illustrated by composition formula in Table 1 were provided. Based on the total weight of the raw material, the content of Mn was 1wt％, the content of Mg was 1wt％, the content of La was 0.2wt％, and the balance was Al. Mn was provided in a form of Mn-Al alloy, La was provided in a form of La-Al alloy, and the others were provided in a form of pure metal.

These raw materials were smelted and cooled to form an aluminum alloy. And then the aluminum alloy was molded on a 160T cold chamber die casting machine, thus obtaining a die casting A1 of the aluminum alloy. In the molding process, the casting temperature was 750℃, the injection speed was 2m/s, the mould temperature was 200℃, and the casting size was 200mm×30mm×3mm.

The surface hardness and tensile strength of the aluminum alloy were tested and the results were recorded in Table 1.

2) Preparation of aluminum alloy product

After degreased and acid pickled, the die casting obtained from step 1) was immersed in an electrolyte to subject to an anodic oxidation, and an oxide film layer with a thickness of 20μm was formed on the surface of the die casting. Then the die casting with an oxide film layer was immersed in an aqueous colorant solution having a rose red color, thus obtaining a rose red oxide film layer. At last, the colored die casting was immersed in distilled water having a pH of value of 5.5, and the distilled water was heated to a boil and kept at the boil for 20min to seal pores in the surface of the oxide film layer, thus forming an aluminum alloy product. The effects of anodic oxidation and coloring were recorded in Table 1.

Example 2

In this example, an aluminum alloy and an aluminum alloy product were prepared by methods which are substantially the same as those in Example 1, with the following exceptions.

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 2.5wt％, the content of Mg was 1wt％, the content of La was 0.2wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

The die casting obtained from step 1) of this example was used. The effects of anodic oxidation and coloring were recorded in Table 1.

Example 3

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 4wt％, the content of Mg was 1wt％, the content of La was 0.2wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Example 4

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 2.5wt％, the content of Mg was 0.1wt％, the content of La was 0.2wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Example 5

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 2.5wt％, the content of Mg was 3wt％, the content of La was 0.2wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Example 6

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 2.5wt％, the content of Mg was 5wt％, the content of La was 0.2wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Example 7

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 2.5wt％, the content of Mg was 1wt％, the content of La was 0.5wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Example 8

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 2.5wt％, the content of Mg was 1wt％, the content of Co was 0.5wt％, the content of La was 0.2wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Example 9

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 2.5wt％, the content of Mg was 1wt％, the content of Co was 2wt％, the content of La was 0.2wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Example 10

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 2.5wt％, the content of Mg was 1wt％, the content of Fe was 1.5wt％, the content of La was 0.2wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Example 11

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 2.5wt％, the content of Mg was 1wt％, the content of Ti was 1wt％, the content of La was 0.05wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Example 12

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 2.5wt％, the content of Mg was 1wt％, the content of Si was 0.3wt％, the content of Cu was 0.8wt％, the content of La was 0.3wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Example 13

In this example, an aluminum alloy and an aluminum alloy product were prepared by methods which are substantially the same as those in Example 7, with the following exceptions.

1) Preparation of aluminum alloy

Based on the total weight of the raw materials, the content of Mn was 2.5wt％, the content of Mg was 1wt％, the content of Ce was 0.3wt％, the content of La was 0.2wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Example 14

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 4wt％, the content of Mg was 1wt％, the content of Zn was 1wt％, the content of La was 0.3wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Example 15

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 1wt％, the content of Mg was 1wt％, the content of Ca was 0.05wt％, the content of La was 0.2wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Comparative example 1

In this comparative example, an aluminum alloy and an aluminum alloy product were prepared by methods which are substantially the same as those in Example 1, with the following exceptions.

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 5.5wt％, the content of Mg was 1wt％, the content of La was 0.2wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

The die casting obtained from step 1) of this comparative example was used. The effects of anodic oxidation and coloring were recorded in Table 1.

Comparative example 2

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 2.5wt％, the content of Mg was 6wt％, the content of La was 0.2wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Comparative example 3

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 2.5wt％, the content of Mg was 1wt％, the content of La was 0.6wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Comparative example 4

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 2.5wt％, the content of Mg was 1wt％, the content of Co was 4wt％, the content of La was 0.2wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Comparative example 5

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 2.5wt％, the content of Mg was 1wt％, the content of Fe was 2.5wt％, the content of La was 0.2wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Comparative example 6

In this comparative example, an aluminum alloy and an aluminum alloy product were prepared by methods which are substantially the same as those in Example 3, with the following exceptions.

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 4wt％, the content of Mg was 1wt％, the content of Ce was 0.2wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Comparative example 7

In this comparative example, an aluminum alloy and an aluminum alloy product were prepared by methods which are substantially the same as those in Example 12, with the following exceptions.

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 2.5wt％, the content of Mg was 1wt％, the content of Si was 0.7wt％, the content of Cu was 0.8wt％, the content of La was 0.3wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Comparative example 8

In this comparative example, an aluminum alloy and an aluminum alloy product were prepared by methods which are substantially the same as those in Example 14, with the following exceptions.

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 4wt％, the content of Mg was 1wt％, the content of Zn was 2wt％, the content of La was 0.3wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Comparative example 9

In this comparative example, an aluminum alloy and an aluminum alloy product were prepared by methods which are substantially the same as those in Example 13, with the following exceptions.

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 2.5wt％, the content of Mg was 1wt％, the content of Ce was 0.45wt％, the content of La was 0.05wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Comparative example 10

In this comparative example, an aluminum alloy and an aluminum alloy product were prepared by methods which are substantially the same as those in Example 10, with the following exceptions.

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 1wt％, the content of Mg was 1wt％, and the balance was Al.

2) Preparation of aluminum alloy product

Comparative example 11

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mn was 2.5wt％, the content of La was 0.2wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Comparative example 12

1) Preparation of aluminum alloy

Based on the total weight of the raw materials of the aluminum alloy, the content of Mg was 1wt％, the content of La was 0.2wt％, and the balance was Al. Surface hardness and tensile strength of the aluminum alloy were recorded in Table 1.

2) Preparation of aluminum alloy product

Table 1

*In the composition formula, numbers represents weight percentages of corresponding elements, based on the total weight of the aluminum alloy.

It can be seen from Table 1 that the aluminum alloy of the present disclosure may have not only a relative high surface hardness and tensile strength, but also a good anodic oxidation performance, therefore an oxide film layer with a relative high quality may be formed on the surface of the aluminum alloy, and an aluminum alloy product with different colors may be provided by coloring the oxide film layer, which may be used in conditions which have high requirements on the surface quality and colors.

Comparing Example 1 and Comparative examples 10-12, it can be seen that the aluminum alloy containing no Mn, Mg or La may have a relative poor anodic oxidation effect, may be deformed easily, and may have a poor casting performance, for example, the die casting of the aluminum alloy may have flow masks on the surface thereof.

Comparing Example 3 with Comparative example 1, it can be seen that, if the content of Mn in the aluminum alloy is 5.5wt％, the hardness and the tensile strength of the aluminum alloy may be improved, but the anodic oxidation performance of the die casting of the aluminum alloy may be poor, for example, the oxide film layer formed on the die casting of the aluminum alloy may have black spots.

Comparing Example 6 with Comparative example 2, it can be seen that, if the content of Mg in the aluminum alloy is 6 wt％, the aluminum alloy may not only have a relative low surface hardness and a relative low tensile strength, but also have a poor anodic oxidation performance, for example, the oxide film layer formed on the die casting of the aluminum alloy may have air pores.

Comparing Example 7 with Comparative example 3, if the content of the rare earth element in the aluminum alloy is 0.6wt％, the aluminum alloy may have a poor anodic oxidation effect, the oxide film layer on the die casting of the aluminum alloy may have dark spots, and the surface hardness and tensile strength of the aluminum alloy may be decreased.

Comparing Example 9 with Comparative example 4, if the content of Co in the aluminum alloy is 4 wt％, the aluminum alloy may have a poor anodic oxidation performance, and the oxide film layer may have hard spots.

Comparing Example 10 with Comparative example 5, if the content of Fe in the aluminum alloy is 2.5wt％, the tensile strength of the aluminum alloy may be decreased, the anodic oxidation performance of the aluminum alloy may be poor, and the oxide film layer formed on the die casting of the aluminum alloy may have hard spots.

Comparing Example 3 with Comparative example 6, if the rare earth element includes Ce, the anodic oxidation of the aluminum alloy may be poor, and the formed oxide film layer may have dark spots.

Comparing Example 12 and Comparative example 7, if the content of Si in the aluminum alloy is 0.7 wt％, the aluminum alloy may have a poor anodic oxidation performance, and the oxide film layer formed on the die casting of the aluminum alloy may have grey spots.

Comparing Example 14 and Comparative example 8, if the content of Zn in the aluminum alloy exceeds 1.6wt％, the anodic oxidation performance of the aluminum alloy may be poor, and the oxide film layer formed on the die casting of the aluminum alloy may have grey spots.

As can be seen from the results of Comparative example 9, based on the total weight of the rare earth element of the aluminum alloy, if the content of La in the rare earth element is less than 20wt％, the anodic oxidation performance of the aluminum alloy may be poor, and the oxide film layer formed on the die casting of the aluminum alloy may have grey spots.

Reference throughout this specification to “an embodiment, ” “some embodiments, ” “one embodiment” , “another example, ” “an example, ” “aspecific example, ” or “some examples, ” means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. Thus, the appearances of the phrases such as “in some embodiments, ” “in one embodiment” , “in an embodiment” , “in another example, ” “in an example, ” “in a specific example, ” or “in some examples, ” in various places throughout this specification are not necessarily referring to the same embodiment or example of the present disclosure. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

Although explanatory embodiments have been shown and described, it would be appreciated by those skilled in the art that the above embodiments cannot be construed to limit the present disclosure, and changes, alternatives, and modifications can be made in the embodiments without departing from spirit, principles and scope of the present disclosure.

Claims

An aluminum alloy, comprising: based on total weight of the aluminum alloy,

1-4wt％ of Mn；

0.1-5wt％ of Mg；

0.002-0.5wt％ of a rare earth element, the rare earth element comprising La, and based on the total weight of the rare earth element, the content of La ranging from 20wt％ to 100wt％；

0-2wt％ of Co；

0-1.5wt％ of Fe；

0-1wt％ of Ti；

0-1wt％ of Cu；

0-1.6wt％ of Zn；

0-0.5wt％ of Si； and

82.9-98.898wt％ of Al.
The aluminum alloy of claim 1, wherein based on the total weight of the aluminum alloy, the aluminum alloy comprises:

1-4wt％ of Mn；

0.1-5wt％ of Mg；

0.002-0.5wt％ of a rare earth element, the rare earth element comprising La, and based on the total weight of the rare earth element, the content of La ranging from 20wt％ to 100wt％；

0-2wt％ of Co；

0-1.5wt％ of Fe；

0-1wt％ of Ti；

0-1wt％ of Cu；

0-1.6wt％ of Zn；

0-0.5wt％ of Si； and

a balance of Al.
The aluminum alloy of claim 1 or 2, wherein based on the total weight of the aluminum alloy, the content of the rare earth element in the aluminum alloy ranges from 0.01wt％ to 0.5wt％.
The aluminum alloy of any of claims 1-3, wherein the rare earth element further comprises Ce, and based on the total weight of the rare earth element, the content of La in the rare earth element ranges from 20wt％ to 99wt％, the content of Ce in the rare earth element ranges from 1wt％ to 80wt％.
The aluminum alloy of any of claims 1-4, wherein based on the total weight of the rare earth element, the content of La in the rare earth element exceeds 40wt％.
The aluminum alloy of any of claims 1-5, wherein based on the total weight of the aluminum alloy, the content t of Mn in the aluminum alloy ranges from 1wt％ to 3wt％.
The aluminum alloy of any of claims 1-6, wherein based on the total weight of the aluminum alloy, the content of Mg in the aluminum alloy ranges from 0.1wt％ to 1wt％.
The aluminum alloy of any of claims 1-6, wherein based on the total weight of the aluminum alloy, the content of Mg in the aluminum alloy ranges from 3wt％ to 5wt％.
The aluminum alloy of any of claims 1-8, wherein the aluminum alloy comprises at least one of the following elements: based on the total weight of the aluminum alloy,

0.1-2wt％ of Co；

0.5-1.5wt％ of Fe； and

0.1-1wt％ of Ti.
The aluminum alloy of any of claims 1-8, wherein the aluminum alloy comprises: based on the total weight of the aluminum alloy,

0-0.8wt％ of Cu；

0-1wt％ of Zn； and

0-0.3wt％ of Si.
A method of preparing an aluminum alloy, comprising:

smelting and cooling a raw material of the aluminum alloy, wherein a composition of the raw material of the aluminum alloy is suitable for forming an aluminum alloy according to any one of claims 1-10.
The method of claim 11, further comprising casting the aluminum alloy.
A method of coloring a surface of an aluminum alloy, comprising the steps of:

anodizing a surface of an aluminum alloy substrate to form an oxide film layer on the surface, and coloring the oxide film layer, wherein the aluminum alloy substrate is a die casting of the aluminum alloy according to any one of claims 1-10.
The method of claim 13, further comprising sealing pores in at least an outer surface of the oxide film layer after coloring the oxide film layer.
An aluminum alloy product, comprising:

an aluminum alloy substrate； and

an oxide film layer formed on at least a part of a surface of the aluminum alloy substrate；

wherein the aluminum alloy substrate is a die casting of the aluminum alloy according to any one of claims 1-10.
The aluminum alloy product of claim 15, wherein the oxide film layer is a colored oxide film layer.