Three-dimensional effects of twinning in magnesium alloys

This article provides experimental evidence on the pronounced three-dimensional surface effects caused by tension twinning at early stages of plasticity of a magnesium alloy. To achieve this goal, multiscale mechanical testing was combined with strain field, texture and surface morphology quantification. The current investigation correlates crystallography-driven, grain-scale surface roughening to the spatially heterogeneous micro- and macrostrain. It was found that tension twinning causes considerable surface extrusions and intrusions across multiple grains that are directly related to severe strain inhomogeneities.