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Ti (C, N) powder is an excellent non-oxide ceramic material. It has a high melting point, high hardness, wear-resistant, corrosion-resistant, anti-oxidation properties and good thermal conductivity, electrical conductivity, and chemical stability, tooling materials Ti (C, N) funds are the main raw material of the ceramic, widely used in many areas of mechanical chemical industry, automobile manufacturing and aerospace. Ti (C, N) powder is a great influence on the performance of the characteristics of the bulk material, the nanoscale powder grain size of the Ti (C, N), there would be a significant improvement in the properties of the materials. Therefore, the powder preparation and organization studies of the structure and properties of nanocrystalline Ti (C, N) to become one of the hot spots of materials science research. Nanocrystalline Ti (C, N) powder preparation technology development status and advances in the laboratory based on nanoscale TiO 2 nano-carbon black as raw materials by carbothermal reduction and nitridation Direct synthesis of nanocrystalline Ti (C, N). By chemical analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) were used to study the phase change and the carbon content of the product of the reaction process, the reaction temperature and time, and the amount of nitrogen on the final The law of the impact of the product, and in combination on this basis, the industrialized production conditions for small batch experiments. The results show that: the carbothermal reduction and nitridation prepared Ti (C, N) Powder by the phase change of the reaction products: nano TiO 2 changes anatase to rutile around 900 ℃ at and C did not react; the TiO 2 reacts with carbon at 1050 ℃ generate cheap titanium oxides Ti of 3 O 5 ; continue to be heated to 1200 ° C, Ti 3 O 5 and C, N phase TiON 2 reaction to produce intermediate Ti3O the reaction is complete, there is a small amount of Ti (CN); to 1250 ℃, have a certain amount of Ti (C, N) generated, which is part of the intermediate phase by TiON reaction; when the temperature was raised to 1300 ° C substantially completely generated Ti (C, N). Generate Ti (C, N) based on thermodynamic analysis, the most suitable temperature should be in the range of 1260 ℃ ~ 1586 ℃. In this experiment, at 1200 ℃ i.e. Ti (C, N) generating, we believe that this may be due to the nano-grade raw materials having a large specific surface area, which has a large specific surface energy, resulting in the reaction is less than the thermodynamic reaction The temperature can be carried out.
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