Effect of creep aging parameters on creep resistance behavior of Al–Cu–Mg alloy

Abstract

The effect of creep aging parameters on the creep resistance of an Al–Cu–Mg alloy was studied in a temperature of 453 K under a constant stress of 250 MPa. It was found that the creep resistance of alloy decreased with increasing temperature and time, and the alloy was more sensitive to the temperature than to the stress in the present experimental conditions. Microstructural observations revealed that the precipitate phases continuously grow in the creep aging process, which weakens the alloy and leads to large creep strain. Moreover, the increase of PFZ at grain boundary also decreased the creep resistance. This study shows that fine and dispersed precipitate phases contribute to creep resistance of Al–Cu–Mg alloy. Thus the process parameters temperature and stress during creep aging forming should be set reasonably to ensure the long-term use of Al–Cu–Mg alloy in service.