Mechanism of texture and microstructure evolution during high temperature plane strain compression in AZ31B and AZ80 magnesium alloys with various initial textures

Abstract

The effects of pre-existent textures on the evolution behaviors of microstructure and texture at high-temperature plane strain compression deformation of AZ31B magnesium alloy have been studied. Deformation is conducted at 723 K with a strain rate of 5.0 x 10(-2) s(-1), up to -1.3 in true strain. When non basal slip systems are the primary slip systems, {11 (2) over bar0}<10<(1)over bar>0> texture develops. In this case, repeated change in microstructure and texture which was found in the previous work appeared with increasing strain. Namely, replacement of {11 (2) over bar0}<10<(1)over bar>0> texture with <10<(1)over bar>0>{11 (2) over bar0} texture and the reverse phenomenon occurs. While the {11 (2) over bar0}<10<(1)over bar>0> oriented grains are small and with wavy shaped grain boundaries, the {10 (1) over bar0}<11<(2)over bar>0> oriented grains are large and with rather straight grain boundaries. The mechanism of repeated change in microstructure and texture is discussed on the basis of preferential dynamic grain growth mechanism proposed by the authors.