Kinetic Monte-Carlo simulation of self-point defect diffusion in dislocation elastic fields in bcc iron and vanadium

Abstract

Simulation of self-point defects (SPDs) diffusion in elastic fields of edge and screw dislocations in slip systems 〈111〉{110}, 〈111〉{112}, 〈100〉{100}, 〈100〉{110} in the temperature range 293–1000K has been performed by the object kinetic Monte-Carlo method for bcc iron and vanadium crystals with dislocation density ∼3×1014m−2. Interaction energies of SPDs (elastic dipoles) with dislocations were calculated by means of the anisotropic theory of elasticity. These elastic interactions significantly change dislocation sink efficiencies. Dislocation sink efficiencies decrease as the temperature increases and tend to the limit value for linear sink without interaction field. The dislocations are more efficient sinks for self-interstitial atoms (SIAs) than for vacancies. The difference between the sink efficiencies for SIAs and vacancies is several times less for screw dislocations than for edge dislocations.