The Microstructures of Ti(C, N)-Mo₂C-Ni Cermet Affected by WC Addition

Abstract

The TiC_0.7N_0.3- and TiC_0.5N_0.5-Mo₂C-WC-Ni cermets were sintered in vacuum or nitrogen (P_N2 ?? 2.7 kPa), and the structural changes were examined in relation to the amount of additional WC(up to 30 vol% in total amount of Ti(C, N) plus WC) and sintering conditions. It was found that an additional WC remained in the structure and the amount increased as the nitrogen content in the cermet and P_N2 increased. This is because WC tends to be checked to dissolve in the surrounding structure (Ti(C, N)-Mo₂C solid-solution) under the conditions as above. Such a non-equilibrium structure having a remaining WC phase is considered to be important for further development of nitrogen contained cermets.