CN111139380A - Novel high-sealing-performance casting aluminum alloy and preparation process thereof - Google Patents

Abstract

The invention discloses a novel high-sealing-performance aluminum alloy for casting, which is characterized by comprising the following chemical components: si, Fe, Cu, Mn, Mg, Zn, Sn, Pb, Sr, Ca 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) nitrogen injection online degassing and 9) casting forming. Compared with the common ZLD107 aluminum alloy in the prior art, a certain amount of Sr is added as an alloy element, so that the silicon eutectic in the alloy is refined, the toughness of the product is improved, and the elongation is improved from 2% to more than 3.5%. The method adopts a nitrogen rotary blowing secondary online degassing technology to effectively remove impurities in the waste aluminum, so that the waste aluminum and pure aluminum have equivalent effect, the product has the characteristics of high purity and higher air tightness.

Description

Novel high-sealing-performance casting aluminum alloy and preparation process thereof

Technical Field

The invention belongs to the field of alloys, and particularly relates to a novel high-sealing-performance aluminum alloy and a preparation process thereof.

Background

With the rapid development of automobile products, the demand of high-sealing aluminum alloy for an automobile air inlet pipe is larger and larger, the currently used ZLD107 aluminum alloy is made of pure aluminum, the cost is high, the sealing performance is unstable, and the execution standard is GB/T8733-2007.

ZLD107 aluminum alloy is a casting aluminum alloy and is difficult to cast due to its low silicon content and poor fluidity. Therefore, it is highly desirable to develop an aluminum alloy product with low cost and high sealing performance.

Disclosure of Invention

In order to solve the problems, the invention provides a novel aluminum alloy for high-sealing casting and a preparation process thereof.

The novel aluminum alloy for casting with high sealing property is characterized by comprising the following chemical components: si: 7.1 to 7.4, Fe <0.3, Cu4.1 to 4.3, Mn <0.1, Mg <0.1, Zn <0.1, Sn <0.01, Pb <0.45, Sr0.025 to 0.050, Ca <0.003, and the balance of Al.

Further, the preparation process of the 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) nitrogen 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 650 ℃ and 750 ℃ 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 the alloy elements to be added into a smelting furnace, controlling the temperature between 680-750 ℃ 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 680-750 deg.c in 2.5-3 kg of refining agent for each ton of molten aluminum, powder spraying refiner with nitrogen as medium and steel pipe to blow into molten aluminum for refining for 30 min;

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 common ZLD107 aluminum alloy in the prior art, the beneficial effects achieved by the invention mainly comprise but are not limited to the following aspects:

1) and a certain amount of Sr is added as an alloy element, so that the silicon eutectic in the alloy is refined, the toughness of the product is improved, and the elongation is improved from 2% to more than 3.5%.

2) Researches find that the calcium content has great influence on the sealing performance of the aluminum alloy, so that the calcium content is controlled to be as small as possible.

3) The method effectively removes impurities in the waste aluminum by adopting a nitrogen rotary blowing secondary online degassing technology, so that the waste aluminum and pure aluminum have equivalent effect, the product has the characteristic of high purity, and the product has higher air tightness. Thus, 20% of waste aluminum can be added, so that the production cost is greatly reduced, and social resources are saved.

Detailed Description

In order to make the technical solution in the present application better understood by those skilled in the art, the following description will be combined

The embodiments of the present application will be described in detail and in full, it is obvious that

The described embodiments are only some embodiments of the present application and not all embodiments. Based on this application

Please refer to the examples, obtained by a person of ordinary skill in the art without any creative effort

All other embodiments are intended to fall within the scope of the present invention.

Example 1

A novel high-sealing casting aluminum alloy is named as LXZLD107 and is characterized by comprising the following chemical components in the following table 1:

TABLE 1

Example 2

The preparation process of the novel high-sealing-property casting aluminum alloy comprises the following steps:

1) melting: firstly, adding the waste aluminum into a smelting furnace, controlling the temperature between 650 ℃ and 750 ℃ 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 the alloy elements to be added into a smelting furnace, controlling the temperature between 680-750 ℃ 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 680-750 deg.c in 2.5-3 kg of refining agent for each ton of molten aluminum, powder spraying refiner with nitrogen as medium and steel pipe to blow into molten aluminum for refining for 30 min;

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 test of the aluminum alloy of the invention and the conventional aluminum alloy comprises the following steps:

the test method comprises the following steps: according to GB/T228.1-2010, an electronic universal tester with the model of CMT5105 is adopted to carry out tensile property (yield strength, tensile strength and elongation), and after the test, the tensile strength of the aluminum alloy is 215MPa, and the elongation is 2.5 percent which is far higher than that of a normal ZLD107 aluminum alloy (the normal ZLD107 aluminum alloy, the tensile strength is 195MPa, and the elongation is 2.0 percent).

The sealing performance of the ZLD107 aluminum alloy is greatly improved compared with the normal ZLD107 aluminum alloy after being used by customers.

And (4) conclusion: the invention greatly improves the sealing performance of the aluminum alloy casting by using pure aluminum added with about twenty percent of waste aluminum as a main raw material through the transformation of a plurality of groups of distribution ratios and processes.

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 novel aluminum alloy for casting with high sealing property is characterized by comprising the following chemical components: si: 7.1 to 7.4, Fe <0.3, Cu < 4.1 to 4.3, Mn <0.1, Mg <0.1, Zn <0.1, Sn <0.01, Pb <0.45, Sr0.025 to 0.050, Ca <0.003, and the balance of Al.

2. The novel aluminum alloy for high-sealing casting as claimed in claim 1, wherein the preparation process of the 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) nitrogen blowing online degassing, and 9) casting and forming.

3. The novel aluminum alloy for high-sealing casting as claimed in claim 2, wherein the preparation process comprises the following steps:

1) melting: firstly, adding the waste aluminum into a smelting furnace, controlling the temperature between 650 ℃ and 750 ℃ 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 the alloy elements to be added into a smelting furnace, controlling the temperature between 680-750 ℃ 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 680-750 deg.c in 2.5-3 kg of refining agent for each ton of molten aluminum, powder spraying refiner with nitrogen as medium and steel pipe to blow into molten aluminum for refining for 30 min;

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.