Molecular dynamics-based simulations to study crack tip interaction with symmetrical and asymmetrical tilt grain boundaries in Zr

摘要

In this article, molecular dynamics based simulations were carried out to study the fracture behaviour of bi-crystalline zirconium (Zr). Atomistic simulations were performed to study the effect of grain boundary configuration on the crack tip behaviour subjected to opening mode of loading. Separate set of simulations were carried out to study the influence of crack orientation on the failure morphology, and strength of bi-crystalline Zr. Disclination shielding of the crack tip stresses induced by grain boundaries, significantly affects the fracture behaviour of bi-crystalline Zr. Opening stresses at the crack tip varied as a function of distance between crack tip and grain boundary plane. Crack propagation and blunting of tip was also predicted as the function of distance from the grain boundary plane. Effect of irradiation induced point defects have also been studied with respect to spatial distribution and number of defects. (C) 2019 Elsevier B.V. All rights reserved.