Oxidation Resistances of Ternary Mixtures of the Carbides of Titanium, Silicon, and Boron

Abstract

Dense compacts of mixtures of Tic, Sic, and B,C were prepared by sintering in an argon atmosphere and by hot pressing. Titanium carbide and B4C reacted during heating to form TiB2. The oxidation resistances of these ternary compacts were determined by the weight gained at 2000OF. in air. Compacts containing 10% B4C, 70 to 50% Tic, and the remainder Sic had superior oxidation resistances. The oxide coating on these compositions consisted of rutile, silica, and a n amorphous third phase. A compact composed of 73.5% Tic, 17% silicon, a n d 9.5% boronwas hot-pressed. It had zero porosity and better oxidation resistance than any other composition tested.