Microstructure evolution of AZ31 Mg alloy during change channel angular extrusion

Abstract

Microstructure evolution of AZ31 Mg alloy during change-channel angular extrusion (CCAE) was investigated. The grains of AZ31 Mg alloy were refined significantly from 500 μm to 15 μm after CCAE deformed at 523 K. Dislocations were induced at the initial stage of extrusion and they rearranged themselves to form dislocation boundaries and sub-grain boundaries during deformation. When the specimen through the horizontal change channel with the strain increased, the sub-boundaries evolved to high angle grain boundaries (HAGB). The process of grain refinement can be described as continuous dynamic recovery and recrystallization (CDRR).

Keywords

AZ31 Mg alloy / grain refinement / change channel angular extrusion (CCAE) / continuous dynamic recovery and recrystallization (CDRR)

References

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