Study on thermal fatigue performance of the molybdenum plate doped with Al2O3 particles

Abstract A thermal fatigue testing machine was designed for evaluating the thermal fatigue resistance of materials with a protective atmosphere. And then, the thermal fatigue resistance of the molybdenum plate doped with Al2O3 particles was investigated, with the crack initiation and extending mechanism discussed. At the test temperature of 900 °C, the thermal fatigue resistance of pure molybdenum plate and composite molybdenum plate is almost equal. At the test temperature of 1200 °C, the crack propagation rate of the composite molybdenum plate is greater than that of the pure molybdenum plate at the prefabricated notch, and the thermal fatigue resistance of the composite molybdenum plate is obviously lower than that of the pure molybdenum plate. However, the anti-crack initiation ability of the composite molybdenum plate is better than that of the pure molybdenum plate, where there is no prefabricated notch.