Decohesion of Σ3(111) Grain Boundary in Tungsten with Boron Interstitial

Abstract

We present the results of atomistic simulations of the decohesion process of the Σ3(111) GB with boron additives. On the basis of the generalized simulated annealing formalism we demonstrate that accounting for angle-dependent three-body interactions leads to the formation of a minimum in the energy profile in the decohesion process and to the enhancement of the boron-induced interatomic interaction across the GB. Our study of the detailed atomic configuration of the GB predicts the effect of the "grain boundary separation" that is induced by the interstitial impurity. The interatomic potentials used in these simulations were obtained from ab initio total energy calculations on the basis of a recursion procedure.