| 초록 |
Thermal shock resistance of Ti(C,N)-Mo2C-Ni cermets was tried to evaluated by the infrared radiation heating method. The method uses a thin circular disk which is heated by infrared ray at the central area with a constant heat flux. The technique makes it possible to evaluate the thermal shock strength (Tss) and thermal shock fracture toughness (Tsf), directly from the electric powder charge and the time of fracture, despite the fact that Tss and Tsf consist of the thermal properties of the material tested. Tsf could be measured for specimens with an edge notch, while Tss could not for the specimens without the notch. It was thought, however, that Tsf might depend on radius of curvature of the edge notch. Using the data of Tsf, Tss was calculated from the consideration of stress concentration. As a result, it was considered that Tss could be applied to evaluation of thermal shock resistance of cermet and thermal shock resistance of Ti(C,N)-Mo2C-Ni cermets increased with an increase in the content of nitrogen and Ni. |
