CN111139383A - Corrosion-resistant aluminum alloy and preparation method thereof - Google Patents

Abstract

The invention discloses a corrosion-resistant aluminum alloy which is characterized by comprising the following chemical components: cu, Si, Mg, Zn, Fe, Mn, Ni, Sn, Pb and Al. The alloy is prepared by 1) melting, 2) sampling detection, 3) adding alloy elements, 4) secondary melting, 5) detection, 6) refining, 7) slag removal, 8) argon blowing online degassing and 9) casting forming. Compared with the ordinary ADC6 aluminum alloy in the prior art, the beneficial effects achieved by the invention mainly comprise but are not limited to the following aspects: 1. by enhancing the control of the magnesium content, the magnesium content is kept at a higher content level, and the corrosion resistance of the alloy is improved. 2. The online degassing is performed by using argon blowing, so that the gas content of the alloy is further reduced, and the cast product has no air holes and sand holes and a brighter surface.

Description

Corrosion-resistant aluminum alloy and preparation method thereof

Technical Field

The invention belongs to the field of alloys, and particularly relates to a corrosion-resistant aluminum alloy and a preparation method thereof.

Background

With the rapid development of the mechanical industry in China, the die-casting aluminum alloy is rapidly applied, and currently, the die-casting aluminum alloy used in industry mainly comprises aluminum-silicon alloy, aluminum-magnesium alloy, aluminum-zinc alloy, aluminum-silicon-copper alloy and aluminum-silicon-magnesium alloy.

The aluminum-magnesium alloy has the greatest characteristics of excellent corrosion resistance and high surface smoothness, and is mainly applied to appearance parts such as automobiles and the like. ADC6 is an alloy mark commonly used in aluminum-magnesium alloy, and has tensile strength of above 266MPa, yield strength of 172MPa and elongation of about 6.4%. ADC6 is a Japanese brand, which is equivalent to the alloy code YLD306 (alloy brand is YAlMg 3D) made in China, and the execution standard is GB/T8733-2007.

In recent years, with the rapid development of the industries such as aerospace, transportation and the like at home and abroad, the requirements on the aluminum matrix composite material are higher and higher. Particularly, for appearance parts, the development of an aluminum alloy with good corrosion resistance and high surface smoothness is a problem to be solved.

Disclosure of Invention

In order to solve the problems, the invention provides the aluminum alloy with good corrosion resistance and high surface smoothness; the invention also provides a preparation method of the corrosion-resistant aluminum alloy.

In order to solve the technical problems, the technical scheme of the invention is as follows:

the corrosion-resistant aluminum alloy is characterized by comprising the following chemical components: cu < 0.08%, Si 0.7-0.85%, Mg 3.0-3.8%, Zn < 0.37%, Fe 0.7-0.8%, Mn 0.42-0.58%, Ni < 0.08%, Sn < 0.08%, Pb < 0.08%, and the balance of Al.

Further, the preparation method of the corrosion-resistant aluminum alloy comprises the following steps: 1) melting, 2) sampling detection, 3) adding alloy elements, 4) secondary melting, 5) detection, 6) refining, 7) slag removal, 8) argon blowing online degassing, and 9) casting and forming.

Further, the preparation process comprises the following steps:

1) melting: firstly, adding the waste aluminum into a smelting furnace, controlling the temperature between 680-780 ℃ to completely melt the waste aluminum, and stirring the aluminum liquid uniformly;

2) sampling and detecting: taking a small amount of aluminum liquid from the furnace, preparing a sample for spectrum detection, and detecting components by a spectrometer;

3) adding alloy elements: calculating the mass of the alloy elements required to be added according to the components detected by the spectrum and the component requirements of the aluminum alloy;

4) secondary melting: adding alloy elements to be added into a smelting furnace, controlling the temperature between 680-780 ℃ to completely melt the alloy elements, and uniformly stirring the alloy elements;

5) and (3) detection: sampling and detecting, and repeating the steps 2), 3) and 4) until the components completely meet the component requirements of the aluminum alloy;

6) refining: refining at 710-760 ℃, blowing 2.5-3 kg of refining agent into molten aluminum per ton of molten aluminum by using a powder injection refiner and nitrogen as a medium through a steel pipe, and refining the molten aluminum for 30 minutes;

7) slag removal: after refining is finished, completely floating slag in the aluminum liquid to the surface, and cleaning the slag on the surface of the aluminum liquid;

8) casting and forming: controlling the temperature in the furnace to be between 700 and 750 ℃ during casting, filtering the aluminum liquid through a launder and a filtering device, casting and molding by adopting a special aluminum alloy casting machine, stacking and packaging to obtain the aluminum alloy casting material.

Compared with the ordinary ADC6 aluminum alloy in the prior art, the beneficial effects achieved by the invention mainly comprise but are not limited to the following aspects:

1. by enhancing the control of the magnesium content, the magnesium content is kept at a higher content level, and the corrosion resistance of the alloy is improved.

2. The online degassing is performed by using argon blowing, so that the gas content of the alloy is further reduced, and the cast product has no air holes and sand holes and a brighter surface.

Detailed Description

In order to make those skilled in the art better understand the technical solutions in the present application, the technical solutions in the present application will be clearly and completely described below with reference to specific embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

A corrosion resistant aluminum alloy designated by the name: LXADC6, the chemical composition of which is shown in Table 1 below:

TABLE 1

Example 2

The preparation method of the corrosion-resistant aluminum alloy comprises the following steps:

1) melting: firstly, adding the waste aluminum into a smelting furnace, controlling the temperature between 680-780 ℃ to completely melt the waste aluminum, and stirring the aluminum liquid uniformly;

2) sampling and detecting: taking a small amount of aluminum liquid from the furnace, preparing a sample for spectrum detection, and detecting components by a spectrometer;

3) adding alloy elements: calculating the mass of the alloy elements required to be added according to the components detected by the spectrum and the component requirements of the aluminum alloy;

4) secondary melting: adding alloy elements to be added into a smelting furnace, controlling the temperature between 680-780 ℃ to completely melt the alloy elements, and uniformly stirring the alloy elements;

5) and (3) detection: sampling and detecting, and repeating the steps 2), 3) and 4) until the components completely meet the component requirements of the aluminum alloy;

6) refining: refining at 710-760 ℃, blowing 2.5-3 kg of refining agent into molten aluminum per ton of molten aluminum by using a powder injection refiner and nitrogen as a medium through a steel pipe, and refining the molten aluminum for 30 minutes;

7) slag removal: after refining is finished, completely floating slag in the aluminum liquid to the surface, and cleaning the slag on the surface of the aluminum liquid;

8) casting and forming: controlling the temperature in the furnace to be between 700 and 750 ℃ during casting, filtering the aluminum liquid through a launder and a filtering device, casting and molding by adopting a special aluminum alloy casting machine, stacking and packaging to obtain the aluminum alloy casting material.

Example 3

The performance tests of the aluminum alloy of the invention and the conventional ADC6 aluminum alloy are as follows:

the test method comprises the following steps: according to GB/T228.1-2010, an electronic universal testing machine with the model of CMT5105 is adopted to test the tensile property (yield strength, tensile strength and elongation), after the test, the tensile strength of the aluminum alloy reaches more than 280MPa, the elongation is about 7.8 percent, and the tensile strength of the original Japanese brand ADC6 is 266MPa, and the elongation is about 6.4 percent. The performance is much higher than that of the conventional ADC6 aluminum alloy.

And (4) conclusion: the invention uses pure aluminum with partial scrap aluminum as raw material through multi-group distribution ratio and process modification, thereby greatly improving the corrosion resistance and surface smoothness of the alloy product.

It is to be understood that the above-described embodiments are only a few, and not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Claims (3)

1. The corrosion-resistant aluminum alloy is characterized by comprising the following chemical components: cu < 0.08%, Si 0.7-0.85%, Mg 3.0-3.8%, Zn < 0.37%, Fe 0.7-0.8%, Mn 0.42-0.58%, Ni < 0.08%, Sn < 0.08%, Pb < 0.08%, and the balance of Al.

2. The corrosion-resistant aluminum alloy as set forth in claim 1, characterized in that the method for preparing the corrosion-resistant aluminum alloy comprises the steps of: 1) melting, 2) sampling detection, 3) adding alloy elements, 4) secondary melting, 5) detection, 6) refining, 7) slag removal, 8) argon blowing online degassing, and 9) casting and forming.

3. A corrosion resistant aluminum alloy according to claim 2 wherein said process comprises the steps of:

1) melting: firstly, adding the waste aluminum into a smelting furnace, controlling the temperature between 680-780 ℃ to completely melt the waste aluminum, and stirring the aluminum liquid uniformly;

2) sampling and detecting: taking a small amount of aluminum liquid from the furnace, preparing a sample for spectrum detection, and detecting components by a spectrometer;

3) adding alloy elements: calculating the mass of the alloy elements required to be added according to the components detected by the spectrum and the component requirements of the aluminum alloy;

4) secondary melting: adding alloy elements to be added into a smelting furnace, controlling the temperature between 680-780 ℃ to completely melt the alloy elements, and uniformly stirring the alloy elements;

5) and (3) detection: sampling and detecting, and repeating the steps 2), 3) and 4) until the components completely meet the component requirements of the aluminum alloy;

6) refining: refining at 710-760 ℃, blowing 2.5-3 kg of refining agent into molten aluminum per ton of molten aluminum by using a powder injection refiner and nitrogen as a medium through a steel pipe, and refining the molten aluminum for 30 minutes;

7) slag removal: after refining is finished, completely floating slag in the aluminum liquid to the surface, and cleaning the slag on the surface of the aluminum liquid;

8) casting and forming: controlling the temperature in the furnace to be between 700 and 750 ℃ during casting, filtering the aluminum liquid through a launder and a filtering device, casting and molding by adopting a special aluminum alloy casting machine, stacking and packaging to obtain the aluminum alloy casting material.