Narrow-granularity thermally-stable tungsten carbide powder and preparation method thereof

Abstract

The invention discloses narrow-granularity thermally-stable tungsten carbide powder and a preparation method thereof, and relates to the technical field of metal powder. The preparation method comprises the following steps: firstly, alternately etching graphite by using hydrogen and oxygen plasmas, and then stripping by using an adhesive tape and ultrasonic airflow to obtain a narrow-granularity graphene nanosheet; the preparation method comprises the following steps: solidifying an ammonium tungstate solution at an ultralow temperature to wrap all graphene nanosheets, and then growing tungsten carbide nanosheets on the surfaces of the graphene nanosheets through an alternating microwave magnetic field to obtain graphene-tungsten carbide-graphene sandwich type nanosheet powder, so that the surface roughness of the tungsten carbide powder is reduced, and the self-lubricating effect of the tungsten carbide powder is realized; the preparation method comprises the following steps: firstly preparing a graphene nanosheet, then modifying the graphene nanosheet by using dimethyl succinic anhydride, 2-chlorobenzoin aldehyde, 2, 5-dimercapto-1, 3, 4-thiadiazole and hydrazine hydrate to form a thicker and compact protective film and an isolating layer, and effectively blocking corrosion elements. The prepared tungsten carbide powder has the effects of narrow particle size distribution, self-lubrication and corrosion resistance.

Description

technical field [0001] The invention relates to the technical field of metal powders, in particular to a narrow particle size thermally stable tungsten carbide powder and a preparation method thereof. Background technique [0002] Tungsten carbide has the advantages of high melting point, high hardness, high strength, high thermal stability and low expansion coefficient, and is widely used in various engineering applications, such as the manufacture of cemented carbide, rock drill bits and thermal spray coatings. In particular, ultra-fine grained cemented carbide has more excellent mechanical properties, and its mechanical properties are determined by the size of tungsten carbide particles in the alloy. When the grain size of tungsten carbide is ultra-fine / nano-scale, it will have higher High hardness and toughness can effectively overcome the contradiction between hardness and toughness in traditional cemented carbide. [0003] In the actual working environment, tungsten c...

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Problems solved by technology

[0003] In the actual working environment, tungsten carbide needs to be used in some extreme environments, such as humid environment and acid environment. In these environments, the existing tungsten carbide generally cannot meet the requirements, and due to the high hardness of tungsten carbide, the friction system The large friction coefficient will cause serious wear, which limits the application of tungsten carbide in harsh environments. Therefore, how to prepare a narrow particle size distribution, self-lubricating, and corrosion-resistant tungsten carbide is particularly important.