Synthesis and Reaction Mechanism of Ti_3SiC_2 by Molten Salt Method from Ti-Si-Fe Alloy

摘要

Titanium silicon carbide (Ti_3SiC_2) were obtained by molten salt synthesis method using the Ti-Si-Fe alloyextracted from high titania blast furnace slag and natural graphite as the raw materials. The phase composition, microscopic structure of the products were characterized by powder X-ray diffraction, scanning electron microscopeandtransmission electron microscope. The influence of firing temperature and chloride salts specieson the phase and morphology of the products were investigated. The results indicated that the synthetic temperature of Ti_3SiC_2 by molten salt synthesis method was about 100 癈, whichwaslower than that without molten salts. The "dissolution-precipitation" mechanism governed the overall molten salt synthesis process. The lamellar Ti3(Si,Al)C2crystal growth obeyedby atwo-dimensional ledge growth mechanism.