Multiscale calculations of dislocation bias in fcc Ni and bcc Fe model lattices

Abstract

a b s t r a c tIn order to gain more insights on void swelling, dislocation bias is studied in this work. Molecular static simulations with empirical potentials are applied to map the dislocation-point defects interaction energies in both fcc Ni and bcc Fe model lattices. The interaction energies are then used to numerically solve the diffusion equation and obtain the dislocation bias. The importance of the dislocation core region is studied under a the temperature range 573-1173 K and the dislocation densities 10 12 -10 15 m À2 . The results show that larger dislocation bias is found in the fcc Ni than in the bcc Fe under different temperatures and dislocation densities. The anisotropic interaction energy model is used to obtain the dislocation bias and the result is compared to that obtained using the atomistic interaction model, the contribution from the core structure is then shown in both the Ni lattice and the Fe lattice.

Formation of Vacancy-Type Dislocation Loops in Hydrogen-Ion-Implanted Fe–Cr Alloy

“…The nature of dislocation loops, e.g., interstitial type or vacancy type, as well as their Burgers vectors, is the key factor for the microstructure evolution of irradiation damage. The bias effect of dislocation loops on point defects would influence irradiation swelling of materials [7]. Gao et al [8] experimentally demonstrated that the bias factor of interstitial-type loops was higher than that of vacancytype loops.…”