Production of Chromium Boride by Thermite Process

Abstract

The alumino-thermite production of Cr-B alloy was studied. Chromium oxides (CrO₃ and Cr₂O₃) and boron oxide were simultaneously reduced by metallic aluminium. Separating from alumina slag, Cr-B alloy was crushed into-100 mesh size. The crushed Cr-B powder was, in the first step, leached in alkaline solution to remove Al which was included by thermite reaction. For further refinement, it was leached in mild acid solution to dissolve other impurities. The refined Cr-B alloy consisted of Cr 60-75%, B 12-25% and Al<5% and it seemed to be composed of CrB and CrB₂ structures.