Preparation of TiC-Ni cermets using composite powders

Conditions for electroless nickel plating on TiC powders were examined, and sintering behavior and structure of sintered compacts using the TiC-Ni composite powder were studied. Annealing TiC powder in hydrogen prior to plating improved nickel plating on TiC powder and densification of composite powder compacts. While for Ni-B plating with dimethylamine borane as the reducing agent, surface activation was necessary for coating, but for Ni-N plating with hydrazine as the reducing agent, nickel deposits were directly formed on TiC powder annealed in hydrogen. Dense compacts made of TiC-Ni composite powder were obtained by liquid phase sintering at 1623K. The contiguity of carbide particles in sintered compacts was markedly reduced by using composite powder, compared with using mixed powder of TiC and Ni.