A Molecular dynamics study on the structure and formation mechanisms of a c+a dislocation in magnesium

Kaburaki, Hideo; Itakura, Mitsuhiro  ; Yamaguchi, Masatake   ; Tsuru, Tomohito   

The generation of non-basal c+a dislocations near the c-axis direction is the key to inducing the widespread plasticity in highly anisotropic hcp magnesium. Using the molecular dynamics method, we have studied the formation process of c+a screw and edge dislocations by compressing the a-axis direction, pependicular to the c-axis, of magnesium single crystal. We found the formation of stacking faults by the emission of basal a-dislocations and also the formation of boundaries consisting of a-dislocations. At the last stage of the deformation process, we confirmed the generation of non-basal c+a dislocations from the stressed junctions of the boundary and stacking faults.