The effects of sintering temperature and time on sintering behavior and mechanical properties in WC-18% TiC-10% Ni alloy were investigated.
When sintering was carried out from 1300℃ to 1500℃ for 1 hr, the nearly maximum values of mechanical properties were obtained at 1450℃. Therefore, at 1450℃, sintering time was varied from 0 to 12 hr. The maximum values of density, transverse rupture strength (TRS) and hardness were all obtained in specimen which was sintered for 4 hr at 1450℃, and values were 10.36 g/㎠, 112 kg/㎟ (=160 Ksi) and R$_A$ 89 respectively.
These values are similar to those of WC-TiC-Co alloy system. As a consequence, it is believed that Ni is suitable for cementing metal for the present WC-18% TiC-10% Ni alloy.
The effects of TiC in the present alloy system are that the solubility of WC in cementing metal Ni is decreased and that over-sintering is suppressed. The suppression of over-sintering is due to decreasing the solubility of WC in cementing metal Ni and precipitation of WC in TiC by forming (TiㆍW)C.
Sintering was gradually completed with elimination of pore and formation of (TiㆍW)C.
