High-Cycle Fatigue Properties and Life Prediction of ZK30 Magnesium Alloy at Room and Elevated Temperatures

The influences of temperature on the tensile properties and especially high-cycle fatigue behaviors of ZK30 magnesium alloy are investigated. The results show that the fatigue strengths are 87.5, 67.5 and 62.5 MPa at room temperature, 100 and 140 °C, respectively. In order to evaluate the fatigue life, considering the temperature and loading conditions, a comprehensive 2-parameter model based on the dislocation pile-up model has been proposed. This model could predict the fatigue performance in the testing temperature range by using the fatigue performance data at several temperatures. Furthermore, at a constant stress amplitude, a critical testing temperature exists, where an optimal fatigue life can be found for the present magnesium alloy. This model provides a new clue for evaluating the optimum service temperature of the high-temperature materials.