Investigation of compounds obtained from Ti-Si-C ternary powder system by mechanical alloying and spark plasma sintering

The purpose of this study is to investigate the method of mechanical alloying and its effect on the compounds obtained from the Ti-Si- ternary powder system. According to studies, it has been observed that the mechanical alloying method alone cannot produce pure Ti3SiC2 compound; Therefore, ancillary processes such as annealing heat treatment and plasma spark ignition process have been used. To conduct the research, a powder mixture of Ti, Si, and C with stoichiometric ratio according to the chemical composition of Ti3SiC2, was milled in 3: 1: 2 by an energetic ball milling with balls (with different radious) to powder weight ratio of 20: 1 and a speed of 360 rpm from zero to 20 hours. To evaluate the thermal stability of the formed phases after 20 hours of milling and to determine the mechanism of formation of Ti3SiC2, the 20 h milled sample was subjected to DTA thermal analysis. Then, to clarify the peaks obtained during DTA analysis, the 20 hours milled sample was thermally treated at 1200 ° C and 1400 ° C a for 1 hour under argon atmosphere. X-ray diffraction pattern was used to identify the phases at different milling times and also to identify products obtained from thermal analysis at temperatures of 1200° C and 1400 ° C. The results showed that the increase of the milling time not only increase the purity of Ti3SiC2 but also causes impurities mainly carbide phases, TiC and SiC.