Vacuum Carbosilicothermic Reduction of Zirconium, Hafnium, Vanadium, Niobium, Tantalum, and Chromium Oxides

This paper reports on vacuum carbosilicothermic reduction of zirconium(IV), hafnium(IV), vanadium(V), niobium(V), tantalum(V), and chromium(III) oxides at a temperature of 1600°C, using silicon carbide as a reducing agent. It has been shown that the only phase resulting from the reduction of hafnium oxide is hafnium carbide. The reduction of chromium and vanadium oxides yields only chromium silicide and vanadium silicides, respectively. The reduction of zirconium, niobium, and tantalum oxides leads to the formation of carbides and silicides of the respective metals. No ternary compounds similar to MAX phases have been obtained.