SYNTHESIS OF TITANIUM-SILICON CARBIDE

Synthesis of bulk titanium silicon carbide (Ti3SiC2) from the elemental Ti, Si, and C powders has been accomplished for the first time, using the are-melting and annealing route. The effects of various parameters on the phase purity of the Ti3SiC2 have been examined, including the starting composition of the powders, compaction technique, arc-melting of the samples, and temperature and time of anneal. The best bulk samples, containing about 2 vol% TiC as the second phase, were made from Si-deficient and C-rich starting compositions. Based on electron probe microanalysis data from a number of bulk samples, it appears that Ti3SiC2 exists over a range of compositions; the Ti-Si-C ternary section has been modified to reflect this. The purest samples of the ternary phase were obtained by leaching powders of silicide-containing samples in diluted HF, and contained over 99 vol% Ti3SiC2.