Preparation method aluminum oxide coating tungsten powder

Abstract

The invention discloses a preparation method aluminum oxide coating tungsten powder. Firstly, coating powder formed by coating AlO(OH) on a WO3 surface layer is prepared; then, the coating powder is calcined by 6-12 hours under the condition of 300-500 DEG C; and finally, the coating powder is fully reduced in a hydrogen atmosphere to obtain the aluminum oxide coating tungsten powder. The preparation method prepares an aluminum oxide uniform coating tungsten powder composite material through calcining and secondarily reducing hydrated aluminum oxide coating tungsten oxide powder; the particle diameter distribution of the powder can be controlled through controlling the content of aluminum oxide in the composite material, so that the powder dispersibility is better; the powder finally formed through the calcining and reducing processes has no other impurities; a layer of film is formed on the tungsten particle surface through the generation of aluminum oxide in the reducing process; the film stops the deposition of secondarily reduced tungsten on the surface thereof so as to inhibit the growth of tungsten particles; and the aluminum oxide is mingled to limit the polymerization of tungsten atoms to inhibit the growth of elementary tungsten particles so as to achieve a grain refining effect.

Description

technical field

[0001] The invention relates to the field of preparation of composite nanometer powder, in particular to a preparation method of alumina-coated tungsten powder. Background technique

[0002] High strength, high toughness, high hardness, light weight, high temperature resistance, corrosion resistance and wear resistance are the main development directions of high performance structural materials. With its excellent high temperature resistance, high strength and hardness, tungsten is an irreplaceable key material in many fields, especially in the fields of national defense, aerospace and aerospace. Compared with pure tungsten, the formed alumina-coated tungsten and tungsten alloy can greatly increase the strength of tungsten, refine the grain, reduce the particle size, and increase the mechanical properties of the material such as toughness and tensile strength. An important step in the preparation of alumina-coated tungsten powder is to generate a precursor o...

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