Dislocation-Pressure Interactions

Abstract

There are various ways in which a dislocation can interact with isostatic stress, with most effects being important at elevated stress levels. Some of these that have received extensive attention are the effects of isostatic stress on elastic constants [1–3]; the direct influence of pressure, or the indirect effect via the stress normal to the glide plane, on the Peierls stress, or more specifically the kink formation energy in many metals and alloys [4, 5]; the influence of the degree and symmetry of core splitting of screw dislocations in bcc metals [6–8] as well as some semiconducting crystals and intermetallic compounds [8, 9]; the implementation of core-splitting effects in terms of the general stress tensor [10, 11]; the indirect effect on operative slip systems that modifies geometric hardening [12]; and weak effects on factors such as lattice parameter, vibrational frequency and diffusivity.