INFLUENCE OF ANOMALOUS PHASES ON THE STRENGTH OF TITANIUM CARBIDE BASE CERMETS.

The transverse-rupture strength of TiC-Mo//2C-Ni cermets was investigated at temperatures from room temperature to 1000 degree C to determine the influence of anomalous phases (Ti//xS) in the cermets formed by the existence of a small amount of sulfur impurity contained in the starting material of titanium carbide powder. It was found that the strength of usual cermets was lower than that of special cermet free from sulfur impurity: because, in usual cermets, Ti//xS phases or larger pores for fracture sources were apt to appear at low temperatures and the intrinsic strength decreased at high temperatures. It was shown that the cermets should be free from sulfur impurity and of high carbon for a further increase in strength.