A study of mechanical anisotropy of Mg–Zn–Rare earth alloy sheet

Abstract

Rolled Mg–Zn–Rare earth sheet after annealing was deformed at room temperature with the tensile axis oriented in both the rolling (RD) and the transversal direction (TD). The deformation behaviour of the sheet has been investigated by acoustic emission (AE) and electron backscattered diffraction measurements, where the AE signal analysis correlates the microstructure and the stress–strain curves to the active deformation mechanisms. X-ray diffraction was applied in order to characterize the deformation texture before and after the test in terms of orientation images. The stress dependence of the strain hardening rate exhibits a fairly narrow lift during loading in RD, which seems to correspond with a transition from the initial basal slip to a secondary double prismatic slip, and a broader lift during loading in TD, which indicates the nucleation of tensile twins.