The preference of absorption of point defects by a dislocation taking into account the microscopic structure of the dislocation core

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Abstract
Climb of a straight edge dislocation is considered and general expressions have been obtained for the coefficients characterizing the asymmetry of absorption of point defects by a dislocation (so-called “preferences” or bias factors) taking into account the microscopic structure of the dislocation core and diffusion processes occurring in the core. The calculation has been made at arbitrary relations between the average spacing between jogs on the dislocation (l 0) and the mean free path of a point defect in the dislocation core (λ), determined by thermal emission of the point defect from the core. Here, account is taken of the effect of the elastic interaction of point defects with a dislocation on the kinetics of climb of the dislocation. Our estimates show that in some metals a situation is quite real when a dislocation is not a continuous sink for point defects (i.e. λ ≪ l 0). In this case there occurs an exponential dependence of bias factors on temperature, which is absent from the model of a dislocation as a continuous sink for point defects.