Yanqing Su¹, M. Arul Kumar², Xin Wang³, Yang Hu³, Kehang Yu³, Jiaxiang Wang¹, Subhash Mahajan⁴, Enrique J. Lavernia³, Tim J. Rupert³, Julie M. Schoenung³, Irene J. Beyerlein¹; ¹University of California, Santa Barbara, ²Los Alamos National Laboratory, ³University of California, Irvine, ⁴University of California, Davis

Mg exhibits limited formability at room temperature because its hexagonal-close packed (HCP) structure has a limited number of activated slip systems. As a result, twinning and detwinning play an important role in plasticity of Mg polycrystalline aggregates. Previous research identified a critical spacing between two twins, beyond which their interactions are negligible. Also analyzed were the effects of the crystallographic orientations of neighboring grains on the critical spacing between parallel twins, but not non-parallel twins. Here, we study the interactions between two twins of parallel or non-parallel relation in Mg using a full-field, crystal plasticity-based fast Fourier transform approach. For both parallel and non-parallel twins, the twin thicknesses are systematically varied to inspect their influences on the critical spacing. For non-parallel twins, the effects of the crystallographic orientations of neighboring grains are also explored. Our results provide insights into the underlying mechanisms of deformation twinning in Mg.