Preparation method of spherical zirconium diboride and silicon carbide aggregate powder

Abstract

The invention relates to a preparation method of spherical zirconium diboride and silicon carbide aggregate powder, belonging to the technical field of composite powder materials. The method comprises the following steps: with zirconium diboride and silicon carbide in the mass ratio of (0.5-1):2 as raw materials, preparing a turbid liquid by using the raw materials and absolute ethyl alcohol, and ball-milling and mixing at the speed of 100-400r/min for 2-6h to obtain a precursor, wherein the mass ratio of absolute ethyl alcohol to the raw materials is (1-3):1; adding absolute ethyl alcohol into the precursor, mixing, and placing the mixture into a colloid grinder to grind and emulsify to obtain a mixed turbid liquid of mixed powder and absolute ethyl alcohol, wherein the mass ratio of the raw materials to the sum of absolute ethyl alcohols added twice is 1:(5-8); carrying out agglomeration, nodularization and densification treatment on zirconium diboride and silicon carbide powder in the turbid liquid by using a liquid powder feeder and induction plasma nodulizing equipment to obtain the powder. The method is simple, low in cost, capable of directly preparing the spherical zirconium diboride and silicon carbide aggregate powder from the raw materials, and capable of improving the purity and quality of the spherical zirconium diboride and silicon carbide aggregate powder.

Description

technical field [0001] The invention relates to a zirconium diboride-silicon carbide (ZrB 2 -SiC) spherical aggregate powder preparation method, which belongs to the technical field of composite powder materials. Background technique [0002] With the development of aerospace technology, the speed of aircraft is getting faster and faster, and the temperature inside the engine and the surface of the body is getting higher and higher. Traditional high-temperature alloys have long been unable to meet the use requirements. High-speed aircraft require materials with high strength, low density, excellent thermal shock resistance, corrosion resistance and oxidation resistance. [0003] Zirconium diboride (ZrB 2 ) is a hexagonal metalloid structure compound, which has the advantages of high melting point (3040 ° C), high hardness and excellent chemical stability; silicon carbide (SiC) has the advantages of high strength, high hardness, low thermal expansion coefficient, etc. The ...

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Problems solved by technology

In the process of the above process, a certain amount of organic solvents such as binders, dispersants and foaming agents need to be added. The organic solvents are often not easy to remove. On the one hand, in the process of preparing coatings by plasma spraying, the spray gun will be corroded Parts, causing equipment damage, while introducing impurity components, affecting the performance of zirconium diboride-silicon carbide coating; on the other hand, because the powder obtained by spray drying has not been calcined and densified, the surface of the spherical powder is generally loose and rough , the bonding strength is low. During the coating preparation process, the powder is easily broken during transportation and difficult to enter the center of the plasma flame, difficult to melt, which affects the coating performance

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