Effect of Twin Schmid Factor on the Tension Twinning Activities in a Highly Textured Mg-3Al-1Zn

Abstract

We investigated the effect of twin Schmid factor on the tension twinning of individual grains in deformed textured Mg-3Al-1Zn samples. The samples were deformed to ~3% strain (normal-direction compression and tension, rolling-direction compression and tension, and 45 o compression). Statistical analyses on the electron backscatter diffraction results revealed tension twinning generally obeys the Schmid law for individual grains, regardless of whether the global stress state favors tension twinning or not. The strong dependence of tension twinning on Schmid factor is in contrast to the reported weak correlation of dislocations and Schmid factor in the same material system. Such observations are anticipated to advance the understanding of the Schmid factor effect on the deformation behavior of polycrystalline Mg alloys.