Evolution of Microstructure and Texture During Uniaxial Compression of Cast AZ31Mg Alloy at Elevated Temperatures

Abstract

Isothermal compression on cast AZ31 magnesium alloy was conducted at different deformation conditions (different temperatures and strain rates) to study microstructure development and texture evolution in the alloy. The as-deformed microstructure and texture distribution were investigated using light microscopy (LM), x-ray diffraction (XRD), and electron backscattered diffraction (EBSD). The examination of the flow stress as a function of strain rate showed that grain boundary sliding was not a dominant mechanism in the cast AZ31 alloy. Occurrence of dynamic recrystallization was confirmed by the evaluation of stress-strain curves and LM. The large grain sizes resulted in a coarse pole figures by XRD. To improve the statistical robustness of the pole figures, the results from multiple sample sections were averaged. The averaged result indicated the formation of basal texture at low strains, where basal planes of most grains were perpendicular to the compression axis. EBSD results showed that the texture distribution at small strain was dominated by the orientations of deformed grains. © 2012 Springer Science+Business Media New York and ASM International.