Effect of alloying time on fabrication of Ti3Si(Al)C2 by spark plasma sintering

Abstract

3Ti–Si–2C–0·2Al mixture powders were used to fabricate high purity Ti3SiC2 ceramic through mechanical alloying (MA) and spark plasma sintering (SPS). The effect of ball milling time on the fabrication of Ti3SiC2 by SPS was also investigated. The results showed that the mixed powders were obviously refined after the MA of 5 h. After milling of 10 h, the mixed powders containing TiC, Ti3SiC2 were synthesised by a mechanically induced self-propagating reaction. After further milling to 20 h, the yield powders were refined. Ball milling time had a remarkable effect on SPS fabrication of Ti3SiC2. A shorter milling time of 5 h only helped to increase the Ti3SiC2 content in the sintered bulk. The samples subjected to the MA treatment of 20 h had a fine and dense organisation. Ball milling of 10 h was most beneficial for fabricating dense and high purity Ti3SiC2. Ti3SiC2 bulk with a purity of 96 wt-% was obtained by MA for 10 h and subsequent SPS at 850°C. When sintered at 1100°C, Ti3SiC2 bulk with a purity of 99·3 wt-% and a relative density of 98·9% was obtained.