Abstract
Mg-5wt%Y extruded alloy showed excellent tensile ductility along the extrusion direction. An in situ tensile test with three-dimensional X-ray diffraction (3DXRD) identified prismatic, basal, and pyramidal < a > slip in different grains during deformation based on the analysis of grain rotation. Ex situ slip trace analysis using electron backscatter diffraction confirms the extensive activation of non-basal slip systems, which can explain the high ductility of this material. Critical resolved shear stress (CRSS) ratios between non-basal slip and basal slip are estimated from Schmid factor analysis.