Dislocations in metals and alloys with the hexagonal close-packed structure

Abstract

Atomistic aspects of dislocations in hexagonal close-packed metals are reviewed. Computer simulation studies on the atomic structure of planar faults and dislocation cores have made essential contributions to understanding the wide variety of the plastic deformation behaviour of this class of materials. Stacking faults have been found to be the most important factor governing the core structure and the glide mechanism of dislocations; the preference for the glide plane, the magnitudes of flow stress and the deformation microstructure in various metals can be understood from the stability of the stacking faults in each material. A brief summary of the deformation behaviour of DO₁₉ ordered alloys and intermetallic compounds is also given, focussing on Ti₃Al.