Sub-micron refractory metal boride powder and method for preparing same

Abstract From the Canadian patent

Sub-micron titanium diaboride powder and other hard refractory, metal boride powders, such as zirconium diboride and hafnium diboride powders, are prepared by vapor phase reaction of the corresponding metal halide, e.g. titanium halide, and coron source reactante in the presence of hydrogen in a reaction zone and in the substantial absence of oxygen, either combined or elemental. In a preferred embodiment the metal halide, e.g. titanium tetrachioride and boron source, e.g. boron trichloride reactants are mixed with a hot stream of hydrogen produced by heating hydrogen in a plasms heater. The reaction zone is mainitained at metal boride forming temperature and submicron soild metal boride …