Dependence of tensile and compressive deformation behavior on aging precipitation in rolled ZK60 alloys

Reducing serious tension-compression yield asymmetry is one important concern for wrought Mg alloys. This study aims to exploit the influence of aging time on tensile and compressive deformation behaviors in rolled ZK60 alloy sheets. The experimental results show that the type and amount of precipitates are greatly dependent on aging time at 175 °C. A number of disk-like β′2 precipitates are present after aged for 10 h. However, rod-like β′1 precipitates are observed after 30 h and the amount of disk-like precipitates reduces. The tension-compression yield asymmetry of the as-solution ZK60 specimens is very serious. It is significantly improved with the formation of disk-like precipitates, while becomes worse with the presence of rod-like precipitates and the reduction of disk-like precipitates. This should be attributed to the disk-like and rod-like precipitates have different hardening effects on the main deformation modes of tension and compression deformations in the present ZK60 alloys.