High-silicon aluminum alloy and modification method thereof

Abstract

The application provides a high-silicon aluminum alloy and a modification method thereof, and belongs to the technical field of aluminum alloys.The modification method comprises the following steps: (1) weighing raw materials of an industrial 4032 aluminum alloy; (2) melting the raw materials, adding Al-10Sr intermediate alloy into a smelting furnace at 740-760 DEG C, and keeping warm for 10-20 min; continuously adding Al-12Sn intermediate alloy when the temperature is increased to 770-790 DEG C, and keeping warm for 10-20 min; adding Al-10Dy intermediate alloy, Al-20Ce intermediate alloy and Al-5Y intermediate alloy when the temperature is increased to 800-820 DEG C, and keeping warm for 10-20 min, so as to obtain a melt; and (3) refining the melt by argon for 20-25 min, and sequentially performing casting and homogenization treatment, so as to obtain a high-silicon aluminum alloy ingot.The aluminum alloy improves the performance of the existing 4032 aluminum alloy, and prolongs the service life of a compressor scroll of a vehicle.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of aluminum alloy, and particularly relates to a high-silicon aluminum alloy and a modification method thereof. BACKGROUND

[0002] The 4032 aluminum alloy belongs to the 4 series aluminum alloy, and the main alloy additive is silicon. The 4032 aluminum alloy is widely used for structural parts bearing medium load and complex shape, and a scroll disc of a scroll compressor for vehicle is usually made of the 4032 aluminum alloy. The dynamic disc and the static disc of the traditional scroll disc are both made of the 4032 aluminum alloy, but the wear resistance of the existing 4032 aluminum alloy is low, which affects the service life of the friction pair of the scroll disc. Although some manufacturers will perform surface treatment such as anodic oxidation or nickel plating on the surface of the dynamic disc to enhance the wear resistance of the dynamic disc, the cost is increased. In addition, the 4032 aluminum alloy is prone to porosity defects in the process of casting, which directly leads to the reduction of the processing and use performance of the product. SUMMARY

[0003] The application aims to provide a high-silicon aluminum alloy and a modification method thereof, which improves the wear resistance and strength and other mechanical properties of the traditional 4032 aluminum alloy, alleviates the porosity problem of the aluminum alloy when the product is cast, improves the processing and use performance of the product, and improves the qualified rate of the product.

[0004] In order to achieve the above-mentioned purpose, the application provides the following technical scheme.

[0005] The application provides a modification method of a high-silicon aluminum alloy, and the modification method comprises the following steps.

[0006] (1) weighing the raw material of the industrial 4032 aluminum alloy;

[0007] (2) melting the raw material, adding Al-10Sr intermediate alloy into the smelting furnace at 740-760 DEG C, and keeping warm for 10-20 min; increasing the temperature to 770-790 DEG C, continuously adding Al-12Sn intermediate alloy, and keeping warm for 10-20 min; increasing the temperature to 800-820 DEG C, and simultaneously adding Al-10Dy intermediate alloy, Al-20Ce intermediate alloy and Al-5Y intermediate alloy, and keeping warm for 10-20 min, to obtain a melt;

[0008] (3) refining the melt by argon for 20-25 min, and sequentially performing casting and homogenization treatment to obtain a high-silicon aluminum alloy ingot.

[0009] Further, the addition amount of the Al-10Sr intermediate alloy is 0.3%-0.4% of the mass of the raw material.

[0010] Further, the adding amount of the Al-12Sn intermediate alloy is 0.05%-0.1% of the raw material mass.

[0011] Further, the total adding amount of the Al-10Dy intermediate alloy, the Al-20Ce intermediate alloy and the Al-5Y intermediate alloy is less than 0.1% of the raw material mass.

[0012] Further, the mass ratio of the total adding amount of the Al-10Sr intermediate alloy, the Al-12Sn intermediate alloy, the Al-10Dy intermediate alloy, the Al-20Ce intermediate alloy and the Al-5Y intermediate alloy is 5-6:1:1:1.

[0013] The present application can improve the strength and wear resistance of the high-silicon aluminum alloy by adding the Al-10Sr intermediate alloy and the Al-12Sn intermediate alloy, but the elongation is not ideal. After a large number of formula debugging, the inventors added the Al-10Dy intermediate alloy, the Al-20Ce intermediate alloy and the Al-5Y intermediate alloy, and the elongation of the aluminum alloy was improved. When the mass ratio of the total adding amount of the Al-10Sr intermediate alloy, the Al-12Sn intermediate alloy, the Al-10Dy intermediate alloy, the Al-20Ce intermediate alloy and the Al-5Y intermediate alloy is 5-6:1:1, the elongation of the aluminum alloy is better. However, the inventors found that the adhesion between the aluminum alloy and the nickel alloy layer is low when the aluminum alloy is subjected to nickel plating surface treatment.

[0014] Further, the mass ratio of the Al-10Dy intermediate alloy, the Al-20Ce intermediate alloy and the Al-5Y intermediate alloy is 1:4-6:1-4.

[0015] The researchers learned from the manufacturers of the vortex disc of the vortex compressor for vehicles that the 4032 aluminum alloy sold on the market is prone to porosity defects in the casting process, which directly leads to low product qualification rate and affects the use performance. When the mass ratio of the Al-10Dy intermediate alloy, the Al-20Ce intermediate alloy and the Al-5Y intermediate alloy is 1:4-6:1-4, the porosity problem of the product is improved. The inventors also unexpectedly found that the adhesion between the aluminum alloy prepared under this ratio and the nickel alloy layer is good when subjected to nickel plating surface treatment, which can meet the needs of manufacturers with nickel plating surface treatment. It is speculated that the compatibility of the aluminum alloy components under this ratio with the nickel alloy layer is better.

[0016] In order to improve the high-temperature wear resistance of the aluminum alloy, further, the casting temperature is 750-760℃; the homogenization treatment temperature is 520-530℃, and the time is 20-25h.

[0017] Further, the raw material comprises the following mass percentage components: Si 11.7%-12.4%, Fe 0.3%-0.7%, Cu 0.8%-1.0%, Mg 0.9%-1.3%, Cr 0.03%-0.08%, Ni 0.7%-1.1%, Zn 0.1%-0.2%, and the balance is Al.

[0018] The corrosion resistance of the aluminum alloy is not ideal after the addition of the Al-10Sr intermediate alloy and the Al-12Sn intermediate alloy, and the inventors find that the corrosion resistance of the product is improved when the above aluminum alloy raw material is used. It is speculated that the aluminum alloy is more prone to form a passivation film under this condition, thereby improving the corrosion resistance. The inventors unexpectedly find that the wear resistance of the high-silicon aluminum alloy is also further improved under this condition.

[0019] The application also provides a high-silicon aluminum alloy prepared by the modification method.

[0020] Compared with the prior art, the application has the following advantages and beneficial effects:

[0021] 1. The aluminum alloy improves the strength, wear resistance and other properties of the existing 4032 aluminum alloy, and prolongs the service life of the scroll disc of the vehicle scroll compressor.

[0022] 2. The aluminum alloy of the application alleviates the porosity problem that occurs when the aluminum alloy is cast into a product, improves the processing and use performance of the product, and improves the qualification rate of the product.

[0023] 3. The application can improve the wear resistance of the high-silicon aluminum alloy by adding the Al-10Sr intermediate alloy and the Al-12Sn intermediate alloy, and the elongation of the aluminum alloy is improved after the addition of the Al-10Dy intermediate alloy, the Al-20Ce intermediate alloy and the Al-5Y intermediate alloy.

[0024] 4. The application uses a specific proportion of aluminum alloy raw material components, and the corrosion resistance and wear resistance of the high-silicon aluminum alloy prepared by the application are improved. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the application will be described below in a clear and complete manner. Obviously, the described embodiments are only a part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the application.

[0026] Embodiment 1

[0027] The embodiment provides a modification method of a high-silicon aluminum alloy, and the modification method comprises the following steps:

[0028] (1) weighing raw materials of industrial 4032 aluminum alloy; the raw materials include the following mass fractions: Si 12.0%, Fe 0.5%, Cu 0.9%, Mg 1.1%, Cr 0.05%, Ni 1.0%, Zn 0.15, and the balance is Al;

[0029] (2) melting the raw materials, adding Al-10Sr intermediate alloy into the smelting furnace at 750℃, and keeping for 15 min; increasing the temperature to 780℃, continuously adding Al-12Sn intermediate alloy, and keeping for 15 min; increasing the temperature to 800℃, while adding Al-10Dy intermediate alloy, Al-20Ge intermediate alloy and Al-5Y intermediate alloy, and keeping for 15 min, to obtain a melt;

[0030] (3) argon refining the melt for 25 min, and then sequentially performing casting and homogenization treatment, to obtain high-silicon aluminum alloy ingot.

[0031] The addition amount of the Al-10Sr intermediate alloy is 0.35% of the mass of the raw materials.

[0032] The addition amount of the Al-12Sn intermediate alloy is 0.07% of the mass of the raw materials.

[0033] The total addition amount of the Al-10Dy intermediate alloy, the Al-20Ce intermediate alloy and the Al-5Y intermediate alloy is 0.07% of the mass of the raw materials. The mass ratio of the Al-10Dy intermediate alloy, the Al-20Ce intermediate alloy and the Al-5Y intermediate alloy is 1:5:2.

[0034] The casting temperature is 755℃; the homogenization treatment temperature is 525℃, and the time is 23 h.

[0035] The embodiment also provides the high-silicon aluminum alloy prepared by the modification method.

[0036] Example 2

[0037] The difference between the embodiment and example 1 is that the addition amount of the Al-10Sr intermediate alloy is 0.2% of the mass of the raw materials; the addition amount of the Al-12Sn intermediate alloy is 0.2% of the mass of the raw materials; and the total addition amount of the Al-10Dy intermediate alloy, the Al-20Ce intermediate alloy and the Al-5Y intermediate alloy is 0.3% of the mass of the raw materials.

[0038] Example 3

[0039] The difference between the embodiment and example 1 is that the Al-10Sr intermediate alloy is replaced by Al-5Er intermediate alloy; and the Al-12Sn intermediate alloy is replaced by Al-2Sc intermediate alloy.

[0040] Example 4

[0041] The difference between the present example and Example 1 is that the mass ratio of Al-10Dy intermediate alloy, Al-10La intermediate alloy and Al-5Y intermediate alloy is 3:1:1.

[0042] Example 5

[0043] The difference between the present example and Example 1 is that at 780℃, Al-10Sr intermediate alloy is added into the smelting furnace, and the temperature is kept for 15 min; the temperature is raised to 780℃, and Al-12Sn intermediate alloy is continuously added, and the temperature is kept for 15 min; the temperature is raised to 780℃, and Al-10Dy intermediate alloy, Al-20Ce intermediate alloy and Al-5Y intermediate alloy are added at the same time, and the temperature is kept for 10-20 min to obtain the melt; the casting temperature is 740℃, the homogenization treatment temperature is 550℃, and the time is 20 h.

[0044] Example 6

[0045] The difference between the present example and Example 1 is that the raw materials include the following mass fractions: Si 13.5%, Fe 0.1%, Cu 0.1%, Mg 0.8%, Cr 0.09%, Ni 1.3%, Zn 0.25, and the balance is Al.

[0046] Performance test

[0047] 1. The strength of the aluminum alloy of the example is determined according to GB / T228.1-2010;

[0048] 2. The aluminum alloy of the example is subjected to salt spray CASS test (copper salt accelerated acetic acid salt spray test), and the standard grade is determined;

[0049] 3. The wear resistance of the aluminum alloy of the example is determined using MG-2000 wear testing machine, and the wear loss is calculated, with the unit of mg, wherein the size of the aluminum alloy is φ8mmx12mm; 25℃, load 100N.

[0050] Among them, the 4032 aluminum alloy of Huohu Steel Group Co., Ltd. (mass percentage (%): aluminum Al: balance, silicon Si: 11.0-13.5, iron Fe: ≤1.0, copper Cu: 0.05-1.3, magnesium Mg: 0.8-1.3, chromium Cr: ≤0.10, nickel Ni: 0.50-1.3, zinc Zn: ≤0.25) is used as a control group. The specific results are shown in Table 1.

[0051] Table 1 Performance test results

[0052]

[0053]

[0054] Using the aluminum alloys of Examples 1, 4 and the control group, 100 friction pairs of dynamic and static plates of a scroll plate of a scroll compressor for a vehicle were prepared, the qualified rate of Example 1 was 100%, the qualified rate of Example 4 was 98%, and the qualified rate of the control group was 93%.

[0055] The above describes the preferred embodiments of the present application. It should be noted that, for those skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, which should also be considered as the protection scope of the present application.

Claims

1. A modification method of a high-silicon aluminum alloy, characterized by, The modification method comprises the following steps: (1) weighing the raw material of industrial 4032 aluminum alloy; (2) melting the raw material, adding Al-10Sr intermediate alloy into the smelting furnace at 740-760 ℃, the adding amount of the Al-10Sr intermediate alloy is 0.3%-0.4% of the mass of the raw material, and the temperature is kept for 10-20 min; increasing the temperature to 770-790 ℃, continuously adding Al-12Sn intermediate alloy, the adding amount of the Al-12Sn intermediate alloy is 0.05%-0.1% of the mass of the raw material, and the temperature is kept for 10-20 min; increasing the temperature to 800-820 ℃, while adding Al-10Dy intermediate alloy, Al-20Ce intermediate alloy and Al-5Y intermediate alloy, the mass ratio of the adding amount of the Al-10Sr intermediate alloy, the adding amount of the Al-12Sn intermediate alloy and the total adding amount of the Al-10Dy intermediate alloy, the Al-20Ce intermediate alloy and the Al-5Y intermediate alloy is 5-6:1:1, the mass ratio of the Al-10Dy intermediate alloy, the Al-20Ce intermediate alloy and the Al-5Y intermediate alloy is 1:4-6:1-4, and the temperature is kept for 10-20 min to obtain a melt; (3) argon refining the melt for 20-25 min, and then sequentially performing casting and homogenization treatment to obtain high-silicon aluminum alloy ingot.

2. The modification method of high-silicon aluminum alloy according to claim 1, characterized by, The total adding amount of the Al-10Dy intermediate alloy, the Al-20Ce intermediate alloy and the Al-5Y intermediate alloy is less than 0.1% of the mass of the raw material.

3. The modification method of high-silicon aluminum alloy according to claim 1, characterized by, The casting temperature is 750-760 ℃.

4. The modification method of high-silicon aluminum alloy according to claim 3, characterized by, The homogenization treatment temperature is 520-530 ℃, and the time is 20-25 h.

5. The modification method of high-silicon aluminum alloy according to claim 1, characterized by, The raw material comprises the following mass fractions: Si 11.7%-12.4%, Fe 0.3%-0.7%, Cu 0.8%-1.0%, Mg 0.9%-1.3%, Cr 0.03%-0.08%, Ni 0.7%-1.1%, Zn 0.1%-0.2%, and the balance is Al.

6. High-silicon aluminum alloy prepared by the modification method according to any one of claims 1-5.

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