Microstructure and texture evolution of Mg alloys during twin-roll casting and subsequent hot rolling

Microstructure and texture evolution of Mg-6Zn-1Mn-1Al (ZMA611) and Mg-6Zn-1Y (ZW61) alloys have been investigated. It is shown that recrystallization occurs through a shear (deformation) band nucleation mechanism. Alloy composition has a significant effect on the nature of the deformation bands formed during rolling, resulting in a difference in the orientation of recrystallized grains between the two alloys: double twin-related in ZMA611 and tension twin-related in ZW61. Such a contrast in microstructure results in the two alloys having different (00.2) pole figures. (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.