CORE PROPERTIES AND MOTION OF DISLOCATIONS IN NIAL

Dislocation core structures of [100], [110] and [111] dislocations in NiAl have been studied by molecular static calculations using an embed ded atom potential. The response of dislocation cores to applied homog eneous shear stresses is investigated and the Peierls stresses of stra ight dislocations having edge, screw and mixed character is determined . The results are in many details in excellent agreement with experime ntal observations. The motion of dislocations in single crystals orien ted for hard slip is discussed in a simple line-tension model. (C) 199 8 Acta Metallurgica Inc.