Life assessment of die-cast Mg-5Al-1.7Ca alloys under creep service conditions

The creep rupture behavior of a Mg-5Al-1.7Ca alloy produced via die casting was investigated at temperatures between 423 and 498 K, and the creep rupture life of the alloy was evaluated using the Larson-Miller parameter (LMP). It was demonstrated that the minimum creep rate and creep rupture life followed the phenomenological Monkman-Grant relationship. The value of the LMP was uniquely described by the logarithm of the applied stress when the Larson-Miller constant was set at 20. In addition, the applied stress and the LMP value followed a linear relationship below the yield stress. These results can be utilized to predict the long-term creep rupture life of the alloy under a given temperature condition and applied stress.