Synthesis and analysis of high-purity MoSi₂ powder

By mechanical alloying, high-energy mechanochemistry, chemical synthesis + high-energy ball milling, MoSi₂ powder was synthesized. Its chemical composition and phases were analyzed. The results show that by chemical synthesis + high energy ball milling, high-purity MoSi₂ powder can be efficiently synthesized. The mixed powder of MoO₃, SiC and carbon with x(Mo):x(Si):x(C)=1:3:7 (atomic ratio) is reduced at 1200°C for 12 h in the corundum tube furnace, using mixed gas of 50%Ar-50%H₂ as reductant. The reaction product is MoSi₂-SiO₂ powder mixture, which is immersed in hydrofluoric acid solution to remove SiO₂ powder. Then pure MoSi₂ powder is milled for 4 h by high-energy ball to change its morphology and particle size distribution.