Plastic Deformation Behavior of Bi-Crystal Magnesium Nanopillars with a [Formula: see text] Twin Boundary under Compression: Molecular Dynamics Simulations

In this study, molecular dynamics simulations were performed to study the uniaxial compression deformation of bi-crystal magnesium nanopillars with a [Formula: see text] twin boundary (TB). The generation and evolution process of internal defects of magnesium nanopillars were analyzed in detail. Simulation results showed that the initial deformation mechanism was mainly caused by the migration of the twin boundary, and the transformation of TB into (basal/prismatic) B/P interface was observed. After that, basal slip as well as pyramidal slip nucleated during the plastic deformation process. Moreover, a competition mechanism between twin boundary migration and basal slip was found. Basal slip can inhibit the migration of the twin boundary, and [Formula: see text] twins appear at a certain high strain level ([Formula: see text] = 0.104). In addition, Schmid factor (SF) analysis was conducted to understand the activations of deformation modes.