Effect of Microalloying on Double-hit Compression Behavior of AZ31 Alloy

Abstract

Double-hit compression tests were performed on the AZ31 and AZ31+0.2Ce alloys at 400 °C and 0.1/s. A stress peak was observed in the flow curve at the beginning of the second hit. This hardening phenomenon was attributed to the occurrence of static strain aging due to Al and Ce in solid solution. A stronger strengthening effect was observed in AZ31+0.2Ce due to a greater pinning effect of Ce on moving dislocations. During the second hit, the flow stress first decreased rapidly and then slowly to a certain level. Discontinuous dynamic recrystallization (DRX) occurred in these two alloys at the original grain boundaries. More DRX grains can be observed in the AZ31+0.2Ce alloy. This was because the DRX process was facilitated due to the segregation of Ce at grain boundaries.