Effect of Hot Forging Process Parameters and Ce Addition on the Microstructure and Mechanical Properties of an As-Forged AZ80 Alloy

Herein, Mg-8Al-0.5Zn (AZ80) alloys with different Ce contents (0, 0.2, 0.8, and 1.4 wt%) are designed and prepared. The effects of the forging temperature (250, 300, 350, 400, and 450 degrees C), forging reduction (7.5%, 17.5%, 27.5%, and 37.5%), and Ce addition on the microstructure and compressive properties of the as-forged AZ80 alloy are investigated. With increasing forging temperature, the compressive strength and fracture strain increased due to grain refinement. With an increase in forging reduction, the yield strength and compressive strength were also improved under the action of fine-grain strengthening and work hardening. The results finally reveal that the appropriate forging temperature was 400 degrees C, and the optimized forging reduction was 27.5%. The addition of Ce significantly refined the grains of the as-forged AZ80 alloys, and with addition of 1.4 wt% Ce, the grain size was significantly reduced by approximate to 42.0%. AZ80 alloys with Ce addition obtain remarkable grain refinement effects due to the existence of the Al4Ce phase. The results of tensile tests show that Ce addition effectively improves the tensile properties ascribed to the excellent grain refinement and work hardening effect.