Effect of Ce addition on hot deformation behavior and microstructure evolution of AZ80 magnesium alloy

Abstract

Hot compression tests of AZ80 and AZ80-Ce alloys were conducted on a Gleeble-3800 simulator at strain rates of 0.01–10 s−1 and deformation temperatures of 340–420 °C. The effects of Ce addition on hot deformation behavior and microstructure evolution of AZ80 magnesium alloys were investigated. The rare earth phase formed with added Ce hindered movement of the dislocations and grain boundaries, causing higher peak stress of AZ80-Ce alloy than that of AZ80 alloy. Existing large-size Al4Ce particles as second phase in AZ80-Ce alloy increased the driving force of recrystallization, promoting dynamic recrystallization and reducing dislocation density. After hot compression, AZ80 alloy showed a fiber texture with the c-axis parallel to the compression direction, and addition of Ce caused texture-weakening. The constitutive equations and processing maps of AZ80 and AZ80-Ce alloys were constructed and analyzed. Adding Ce reduced deformation activation energy and Zener-Hollomon parameter, and enlarged non-instability zone in processing maps of AZ80 alloy.

Keywords

• Hot compression
• Microstructure evolution
• Hot deformation behavior