Microstructure and Mechanical Properties of AZ31 Alloys Processed by Residual Heat Rolling

Abstract

To produce high strength and ductility Mg alloys with high productivity and low energy consumption, the residual heat rolling (RHR) process was initially proposed. The microstucture and mechanical properties of AZ31 processed by RHR were investigated by optical micrscopy (OM), electron backscatter diffraction (EBSD), and electron universal testing machine. The yield strength (YS), ultimate tensile strength (UTS), and elongation to failure of RHRed AZ31 sheet were 194 MPa 311 MPa, and 22%, respectively. The RHRed AZ31 alloys after annealing have very fine and homogeneous grains. The symmetrical rolled (SR) and RHRed AZ31 exhibit typical {0002} basal textures. The RHRed AZ31 has double-peak basal texture distribution. The basal poles of RHRed AZ31 split from normal direction (ND) to rolling direction (RD). There are few hard orientation distributions on the basal <a> slip and more soft orientation distributions on the prismatic <a> slip in the RHRed AZ31 sheets than those in the SRed AZ31sheets.

Keywords

magnesium alloys / microstructure / texture / grain refinement / mechanical properties / residual heat rolling

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