Electronic effect of boron impurity on the kink in bcc iron

Using the first-principles self-consistent discrete variational method based on the density functional theory, we have investigated the effect of B impurity on the kink in the [1 0 0](0 1 0) edge dislocation in bcc iron. Our energetic calculations show that the B has a strong segregation tendency to enter the kink. The structural energy, the interatomic energy, the partial density of states, and the charge density difference are also calculated in the present paper. All the results indicate that B in the kink can enhance the interatomic interaction between the impurity atom and the neighboring Fe atoms due to the hybridization of B 2p-Fe 3d4s4p orbitals. The introduction of B impurity leads to a strong pinning effect on the dislocation motion in bcc iron.