Effect of TiC Content on Oxidation Behavior of Sintered WC-TiC-TaC Alloys

The effect of TiC content on oxidation behavior of the sintered WC-TiC-TaC alloys with 2 mass% TaC and different TiC amount of 3-45 mass% was investigated through oxidation tests in air at 973K in order to clarify their oxidation mechanism at high temperature. Based on the results of mass change, SEM observation, elemental map analysis and composition analysis of the samples before and after the oxidation test, it was revealed that with increasing TiC content in the alloys, mass changes from oxidation and thickness of the oxidation scale decreased. Thus, it is considered that the main component of the scales changed from WO3 to TiO2 gradually with increasing TiC content in the alloys, and oxygen diffusing through the oxidation scale to the alloys was inhibited more and more.