AlN plastic deformation between room temperature and 800 degrees C - II. Dislocation core structures in basal and prismatic planes

摘要

Observations of dislocation substructures have shown that the basal and first-kind prismatic planes are easily activated in plastically deformed aluminium nitride between room temperature and 800 degrees C as shown in the companion paper, part I. In this paper, several analyses are performed to determine the ability of dislocations to glide in one plane relative to others. According to the closest-packed criterion, the first-kind prismatic plane appears to be favoured. Line energy calculations under anisotropic elasticity do not allow one to conclude the preferential activation of one of the glide planes. The crystallographic structures of basal and first-kind prismatic planes, core structures of dislocations and dissociation reactions are investigated and stacking-fault configurations in prismatic planes are proposed. [References: 20]