A stress-gradient based criterion for dislocation nucleation in crystals
Dislocations are the main lattice defects responsible for the strength and ductility of crystalline solids. The generation of new dislocations is an essential aspect of crystal defect physics, but a fundamental understanding of the mechanical conditions which lead to dislocation nucleation has remained elusive. Here, we present a nucleation criterion motivated from continuum thermomechanical considerations of a crystalline solid undergoing deformation, and demonstrate the criterion's ability to correctly predict dislocation nucleation via direct atomistic simulations. We further demonstrate that the commonly held notion of a nucleation criterion based on the magnitude of local stress components is incorrect.
|Keywords||Atomistic simulation, Dislocation mechanics, Dislocation nucleation|
|Journal||Journal of the Mechanics and Physics of Solids|
Miller, R, & Acharya, A. (Amit). (2004). A stress-gradient based criterion for dislocation nucleation in crystals. Journal of the Mechanics and Physics of Solids, 52(7), 1507–1525. doi:10.1016/j.jmps.2004.01.007