Abstract: The thermal fatigue resistance of chrome-tungsten alloy white cast iron is studied by Belt-constraint. The changes of microstructure before and after thermal cycling are observed by TEM. The fracture of thermal fatigue is also observed by SEM. The results demonstrate that the matrix microstructure of materials tested occurs dynamic recovery and recrystallization and generate cyclic softening in the process of thermal cycling. The resistance to thermal fatigue is property improved by raising quenching temperature. However, excessive quenching temperature may lower thermal fatigue resistance.

Key words: Quenching temperature, Thermal fatigue, White cast iron