Effects of manganese and rare earth elements on the microstructural evolution and deformation behaviour of the anode materials of AZ61 magnesium alloy

Abstract

The microstructural evolution of AZ61 alloys derived via a hot compression process, with different contents of manganese (Mn) and rare earth elements were investigated. The results showed that the morphology of Mg17Al12 was gradually changed when the Mn/RE ratio decreases from 1 to 0.3. A new Al4RE phase was formed with the addition of RE elements and the amount of Al8Mn5 increased with the increase of Mn. The optical microscopy images of the samples treated at 400°C for 10 h revealed that the Mg17Al12 phase was dissolved into α-Mg matrix. The hot compression treatment resulted in dynamic recrystallisation of the AZ61 alloys, of which the Al4RE phase with needle-like changed in morphology compared with the heated alloys. The degrees of dynamic recrystallisation of the alloys with additives of Mn and RE became higher than those of the alloys without Mn or RE elements.