In situ mapping of deformation twinning evolution in Mg by nano-3DXRD CT

The proposal aims at investigating deformation twinning (DTw) processes in pure Mg, using nano-3DXRD CT, during in situ tensile testing, at several successive deformation steps and while the materials is under load. Crystal orientations, crystal defects and the full local stress tensor will be mapped in the materials during twin initiation and its progressive propagation. Single crystal and polycrystalline samples will be tested, with a focus on the role of slip in twin initiation and propagation mechanisms, as well and the stresses associated with twin-twin and twin-grain boundaries, and twin slip-planes interactions. After the test campaign at ESRF, post-mortem 3D HR-EBSD and detailed TEM analyses will be done on the deformed materials. These experiments will be a unique chance to close the gap between computer modelling and experiments. They will answer several fundamental and debated questions about the roles of local stresses and crystal defects in DTw mechanisms in hcp metals.