The Effect of {1012} Twin Boundary on the Evolution of Defect Substructure

摘要

Pure Mg single crystals were deformed at room temperature along two orientations in sequence, in order to activate a specific dislocation slip mode followed by {1012} twinning. The defects in both the matrix and twin crystals were analyzed with a transmission electron microscope (TEM). This study reveals the collective evolution of the defect substructure when a dislocated crystal is 'invaded' by a moving twin boundary. When primarily [c]-containing defects in the matrix were incorporated by a moving twin boundary, including 〈c + a〉, pure [c] dislocations and I_1 stacking faults, the twin contains homogeneously distributed I_1 stacking faults, which in some instances appear to be connected on twin boundary to the faults in the matrix.