Method for preparing carbonized titanium powder by vacuum carbothermal reduction

Abstract

The invention relates to a method for preparing carbonized titanium powder by vacuum carbothermal reduction. A method of vacuum metallurgy is adopted, and the method comprises the following steps: taking titanium dioxide and carbon as raw materials, wherein the mass ratio of the titanium dioxide to the carbon powder is 20:9-21; after crushing and briquetting, entering a vacuum furnace; heating the materials to the temperature of between 1,300 and 1,600 DEG C at a heating rate of 10-15 DEG C per minute; and keeping the temperature for 2 to 10 hours, and controlling the pressure in the furnace to between 10 and 100 Pa. Therefore, the materials undergo vacuum carbothermal reduction reaction, and ultra-fine carbonized titanium powder is prepared.

Description

1. Technical field [0001] The invention relates to a method for preparing titanium carbide powder by vacuum carbothermal reduction, which belongs to the technical field of vacuum metallurgy. 2. Background technology [0002] Titanium carbide contains 20.05% carbon and is a gray powder with a NaCl type cubic crystal structure. The density is 4.93 g / cm 3 Melting point: 3160°C, boiling point: 4300°C; with high melting point, high strength, high hardness and high elastic modulus, good thermal shock resistance and chemical stability, high temperature oxidation resistance is only lower than silicon carbide, is a cemented carbide Therefore, it is widely used as a hard phase in structural materials to make wear-resistant materials, cutting tool materials, mold manufacturing, mechanical parts, etc. It can also be used to make crucibles for melting tin, lead, cadmium, zinc and other metals. Transparent titanium carbide ceramics are excellent optical materials; the excellent thermal s...

AI Technical Summary

Problems solved by technology

Industrial titanium carbide powder is originally carbon black reduced TiO 2 Synthesized, the reaction temperature is 1700 ° C ~ 2100 ° C, the time is 10 ~ 24 h, and the gas protection atmosphere is carried out in a tube furnace or an electric arc furnace. Due to uneven mixing of materials, the carbon source is in TiO 2 The distribution in the medium is limited, the material is affected by the diffusion gradient during the reaction, and there is unreacted TiO after the reaction 2 and carbon, often making the synthetic powder less pure

The direct reaction method takes 5 to 20 hours to react, and it is difficult to control the temperature during the exothermic reaction process, and the reactants are easy to agglomerate, so it must be ground and processed to prepare micron-sized TiC powder

Although the self-propagating combustion synthesis method can burn and synthesize TiC in a short time, the heat released in an instant will cause the product particles to agglomerate and the crystal grains to grow, and it is difficult to obtain fine powder.