CN111286654A

CN111286654A - High-performance magnesium alloy and preparation method thereof

Info

Publication number: CN111286654A
Application number: CN202010285310.8A
Authority: CN
Inventors: 梅小明; 杨春林; 单建鹏; 张国峰
Original assignee: WUTAI YUNHAI MAGNESIUM INDUSTRY CO LTD
Current assignee: WUTAI YUNHAI MAGNESIUM INDUSTRY CO LTD
Priority date: 2020-04-13
Filing date: 2020-04-13
Publication date: 2020-06-16

Abstract

A high-performance magnesium alloy and a preparation method thereof belong to the technical field of magnesium alloy preparation, and aim at providing a high-performance magnesium alloy and a preparation method thereof. The high-performance magnesium alloy comprises the following components in percentage by mass: al: 5.7-6.5%, Zn < 0.2%, Mn: 0.25-0.4%, Fe < 0.0040%, Cu < 0.0080%, Si < 0.05%, Ni < 0.0010%, Be: 0.0005-0.0015%, Ca < 0.0150%, Re: 0.2-0.4%, Sr2.4-3.1%, and the balance being Mg. The high-performance magnesium alloy produced by the invention has good refined alloy grain performance, the corrosion resistance can reach 9 grades of ASTM standard, and the corrosion resistance requirement of an ideal state is met.

Description

High-performance magnesium alloy and preparation method thereof

Technical Field

The invention belongs to the technical field of magnesium alloy preparation, and particularly relates to a high-performance magnesium alloy and a preparation method thereof.

Background

Magnesium alloy is the lightest metal structure material at present, the specific gravity is only 1.8, 1/3 of aluminium and 1/4 of iron are respectively, its specific strength is up to 133, have relatively higher specific modulus at the same time, good electric conduction, heat conduction, casting, dimensional stability and other advantages, these excellent performances make magnesium alloy replace other metal structure materials at present gradually, have been used in fields such as car, electron, household electrical appliances, communication and aerospace widely, etc., reach the purpose of lightweight, become important modern industrial material, also be known as the green environmental protection structural material of 21 century.

However, with the diversification of the market application of magnesium alloys, the conventional magnesium alloy products cannot meet the requirements in corrosion resistance, creep property, mechanical property, processability and the like required by certain high-end technical fields, so that the popularization and application of the magnesium alloys in special fields are limited to a certain extent.

With the global wide attention on environmental protection, the demand for developing the energy-saving and emission-reducing green automobile industry is increasingly urgent, so that the magnesium alloy is more and more widely applied to the lightweight development of automobiles, the diversified development of the magnesium alloy series needs to be promoted, and the application in more professional technical fields is met.

Disclosure of Invention

The invention aims to provide a high-performance magnesium alloy and a preparation method thereof.

The invention adopts the following technical scheme:

a high-performance magnesium alloy comprises the following components in percentage by mass: al: 5.7-6.5%, Zn < 0.2%, Mn: 0.25-0.4%, Fe < 0.0040%, Cu < 0.0080%, Si < 0.05%, Ni < 0.0010%, Be: 0.0005-0.0015%, Ca < 0.0150%, Re: 0.2-0.4%, Sr2.4-3.1%, and the balance being Mg.

A preparation method of a high-performance magnesium alloy comprises the following steps:

firstly, smelting, preparing raw materials according to a proportion, adding 200kg of molten salt, adding pure magnesium ingots, stirring and refining after the raw materials are completely molten, respectively adding other raw materials, adding strontium, adding pure strontium after the refining temperature reaches 750 ℃, and sampling and analyzing alloy components after the raw materials are fully alloyed by stirring and heating;

and secondly, casting, after the alloy components are detected to be qualified, standing, and then starting converter continuous casting, wherein the casting temperature is not lower than 730 ℃, the mould temperature is not lower than 150 ℃, the casting area is protected by a gas permeable body, and after the alloy ingot in the mould is cooled to normal temperature, the high-performance magnesium alloy can be obtained.

The invention has the following beneficial effects:

1. the high-performance magnesium alloy produced by the invention has good refined alloy grain performance, the corrosion resistance can reach 9 grades of ASTM standard, and the corrosion resistance requirement of an ideal state is met.

2. The high-performance magnesium alloy produced by the invention has good high temperature resistance, and can meet the metal performance requirement of high temperature resistance of more than 175 ℃ and high strength without deformation.

3. The high-performance magnesium alloy produced by the method can improve the fluidity of high-temperature liquid during die casting, reduce the problem of component change caused by oxidation burning loss during secondary remelting and save the production cost;

through analysis and detection, the magnesium alloy has obvious properties. Compared with the conventional AM60B alloy, the fracture detection has the advantages that the crystal grains are finer and the structure is more uniform; the corrosion resistance is tested by simulating seawater corrosion for 12 hours, and the performance is improved by 2 grades; the internal metallographic structure is observed under a microscope of 500 times, and the structure is compact, and has no shrinkage cavity and no impurities.

Through tracking and using feedback, each performance of the die casting is excellent. Compared with the conventional AM60B alloy, the product has the yield strength of 141 (130 of the conventional AM 60B), the tensile strength of 232 (220 of the conventional AM 60B), and the maximum working temperature of the die-cast product of the material can reach 175 ℃.

The product has the advantages of feeding back test data in the die-casting process, having better fluidity than the conventional AM60B alloy and improving the die-casting yield by 7.5 percent.

Drawings

FIG. 1 is a 7-grade diagram of a conventional magnesium alloy salt spray;

FIG. 2 is a 9-grade diagram of a magnesium alloy salt spray prepared by the present invention;

FIG. 3 is a three-level metallographic view of a conventional magnesium alloy;

FIG. 4 is a first-order metallographic image of a magnesium alloy prepared according to the present invention.

Detailed Description

firstly, smelting, preparing raw materials in proportion, adding 200kg of molten salt, adding pure magnesium ingots, stirring and refining after the raw materials are completely molten, monitoring the change of refining temperature timely, adding other raw materials respectively, adding prepared strontium, adding pure strontium after the refining temperature reaches 750 ℃ to ensure the full dissolution of the strontium, and sampling and analyzing alloy components after the raw materials are fully alloyed by stirring and heating;

and secondly, casting, after the alloy components are detected to be qualified, standing, and then starting converter continuous casting, wherein the casting temperature is not lower than 730 ℃, the mold temperature is not lower than 150 ℃, the casting area is protected by a gas permeable body, and after the alloy ingot in the mold is cooled to the normal temperature, the AJ62 high-performance magnesium alloy can be obtained.

Claims

1. A high-performance magnesium alloy is characterized in that: the paint comprises the following components in percentage by mass: al: 5.7-6.5%, Zn < 0.2%, Mn: 0.25-0.4%, Fe < 0.0040%, Cu < 0.0080%, Si < 0.05%, Ni < 0.0010%, Be: 0.0005-0.0015%, Ca < 0.0150%, Re: 0.2-0.4%, Sr2.4-3.1%, and the balance being Mg.

2. A method for preparing the high-performance magnesium alloy according to claim 1, wherein: the method comprises the following steps: