Optimization of the Carbosilicothermic Synthesis of the Ti4SiC3 MAX Phase

Abstract

We have studied the formation of the Ti4SiC3 MAX phase during the vacuum carbosilicothermic reduction of TiO2 with a combined reducing agent consisting of SiC and elemental Si and analyzed the effects of the synthesis temperature, heat treatment time, and percentage of elemental silicon in the starting mixture on the Ti4SiC3 yield. Optimal Ti4SiC3 synthesis conditions are as follows: temperature from 1550 to 1650°C, isothermal holding time of 360 min, and the starting-mixture composition TiO2 + 1.2SiC + 0.6Si. The Ti4SiC3 yield then reaches 92 wt %.