Magnesium-based composite material and method for forming magnesium-based composite material parts

Abstract

The invention discloses a semi-solid-state moulding method of magnesium base composite material or parts made of magnesium base composite material. In atmosphere of protective gas, magnesium alloy powder and wild-phase powder are uniformly mixed by stirring to obtain mixed powder. The mixed powder is then added into a cold pressing appliance with a regular internal chamber to carry out cold pressing, so as to obtain a billet of the composite material; wherein, the shape of the billet is corresponding to the shape of the internal chamber of the cold pressing appliance. The billet of the composite material is placed into a heating device to be heated, so as to obtain a semi-solid-state mixture of solid and liquid. The mixture of solid and liquid is injected to fill a die cavity of a die, soas to obtain the magnesium base composite material or the parts made of magnesium base composite material of the corresponding shape. The method of the invention effectively avoids oxidation and other pollutions and has high safety, simple technical process and low cost.

Description

technical field [0001] The invention relates to a method for preparing a metal-based composite material, in particular to a method for preparing a magnesium-based composite material and parts of the magnesium-based composite material. Background technique [0002] Magnesium alloys are made by adding alloying elements to pure magnesium. Alloying elements commonly used in magnesium alloys include aluminum, zinc, manganese, zirconium and rare earth elements. Magnesium alloys have special excellent properties of small specific gravity and high specific strength. However, as a structural material, its hardness, stiffness and wear resistance are not ideal enough, so its application is limited. By adding hard particles to the magnesium alloy, a discontinuously reinforced magnesium-based composite material can be prepared. In this composite material, the magnesium alloy is the matrix, and the hard particles are the reinforcement (also known as the reinforcement phase or the second ...

AI Technical Summary

Problems solved by technology

The first is the liquid phase forming method, also known as the casting method. When using this method to prepare metal matrix composites, it is easy to produce reinforced phase segregation, harmful interfacial reaction between the matrix and the reinforced phase, coarse structure, uneven composition, and easy Drawbacks such as inhalation of gases and impurities, and a low volume fraction of the reinforcing phase, which lead to a reduction in the mechanical properties of the material

[0004] The second is the solid phase forming method, also known as the powder metallurgy method, which can better avoid some defects in the casting method, such as controllable volume fraction, fine structure, uniform composition, etc., but the powder metallurgy process is complicated, Easy to pollute, small material size, long production cycle, low production efficiency, which restricts its wide application

The preparation method needs to be sintered in a vacuum environment, and the hot extrusion requires high pressing pressure, harsh conditions, and complicated process, so that the size of the prepared composite material is limited.

[0005] The third is the spray co-deposition method. When the spray deposition method is used to prepare magnesium-based composite materials, the process is complicated, the equipment requirements are high, the investment is large, and the cost is high.

In addition, the method of directly heating the metal powder is easy to cause the powder to oxidize during the heating process, thereby affecting the performance of the material

In addition, the activity of magnesium alloy powder is very high, so there is a danger of explosion