Abstract

The effects of the carbon content ranging from 17.5 to 21.0 wt.% in TiC-30vol.% Ni_3Al cenmet and the Mo_2C content raging from 0 to 30 wt.% in TiC-20 vol.% Ni_3Al cermet were investigated in the relation to the microstures and harbness. The speciment were sintered at 1400°C, 1430°C and 1450°C for 60minutes. The results were summarized as follows; 1) The shrinkages and relative densitites of the specimens were incrased up to 20.0 wt.% C and then decreased. 2) The grains of TiC were almost the same size with the different content of carbon. Free carbons were appeared on the microstrures when carbon was added over 20.5 wt.% while TiC and Ni_3All were formed when carbon was added below 20.0 wt.%; 3) The lattice parameters of the Ni_3Al and TiC phases were increased up to 20.5 wt.% C, and then saturated. 4) The hardess was increased up to 20.0 wt.% C, and then decreased. 5) The Mo_2C made the TiC grains fine and the surrounding structure around TiC gains. 6) The micropores were decreased with increasing the binder and the sintering temperature. 7) The lattice parameter of the Ni_3All ana TiC were almost the samp up to 10 wt.% Mo_2C and then decreased. 8) The hatdness was increased up to 5wt.% Mo_2C and then decreased owing to the micrpores. 9) The more the binder phase, the higher the relative density and the proper Mo_2C amount of TiC-Ni_3Al cermets were obtained.