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Silicon carbide, titanium, and zirconium carbide material has a high melting point, high strength, excellent performance, good electrical and thermal conductivity, chemical stability, and high temperature anti-oxidation in metallurgy, machinery, electronics, nuclear industry, bio-materials and aerospace The field has a wide range of applications. A powder having a desired size and a controlled morphology is the basis for the preparation of the above advanced carbide material. Carbide powder preparation process, the reaction temperature and synthetic powder reunion deficiencies, this paper proposes a new method of powder preparation, that is, in the molten salt medium metal heat through the oxide reduction reaction and restore the direct reaction of the metal with the carbon to silicon carbide, titanium carbide and zirconium carbide powder was prepared. The systematic study of the reaction temperature, molten salt composition, preparation of metal / carbon molar ratio, holding time, the composition of the reactants and the ratio and reducing agent type parameters of the synthesized product. Use FactSage software to explore the possibility of reaction, the simulation of thermodynamic processes in molten salt synthesis carbide powder. XRD, SEM, laser particle size analysis, phase composition and morphology were characterized synthetic powder substance than the surface area analysis and other research tools. Analysis of the formation mechanism of the synthesis of silicon carbide powder in the molten salt. The main conclusions are: SiO 2 silicon source and carbon black as carbon source, 750 ℃ ?? 1 100 ℃ of the molten salt media reaction and incubated for 3 hours can be synthesized SiC powder. KCl-NaCl molten salt system generated at 750 ℃ ??existing SiC. KCl molten salt to magnesium metal reductant 1000 ℃ obtained under D 50 is 1.057μm, the ratio of the surface area of ??54.88m 2 / g, the high purity, better dispersion of SiC powder. TiO2 titanium, carbon black as carbon source, TiC powders can be obtained in the 750 ℃ ?? 1 100 ℃ of the molten salt environment. Wherein magnesium metal reducing agent, in the molten salt system of the KCl-NaCl 750 ℃ ??existing TiC phase generated; at 950 ℃ reaction and incubated for 3 hours to prepare a the D 50 0.39 μm, specific surface area of ??the 89.76 m 2 / g of TiC powder. Containing zirconium oxide as a zirconium source, a carbon black as the carbon source, the 800 ° C 1 100 ° C molten salt in the liquid phase can be obtained ZrC powder. NaCl in molten magnesium metal reductant, synthesized at 1000 ℃ D 50 for 18.59μm, the specific surface area of ??15.27m 2 / g of the ZrC powder . Of the three carbide powder phase composition and morphology with synthesis temperature molten salt composition, metal / carbon molar ratio, holding time, the composition of the reactants and the reductants. Under the same experimental conditions: (1) 1000 ° C when the molten salt can be prepared by a higher purity, better dispersion of carbide powder; (2) experiments with molten salt KCl-NaCl salt reaction Preferably, the lowest temperature, the KCl salt synthesized powder morphology and crystallinity; (3) three kinds of carbide powder SiC most susceptible metal reduction in the system, TiC followed. (4) Experimental resulting synthetic product, the smallest particle size of the TiC powder.
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