Micro-Simulation of Crack Tip Plastic Zone and Dislocation-Free Zone
裂纹尖端塑性区和无位错区的微观模拟

Edge dislocation emissions from Mode I, Mode II and mixed-mode crack tips along multiple inclined slip planes are simulated, and plastic zones as well as dislocation-free zones are obtained. It is found that the shape of the Mode II plastic zone is quite different from that obtained based on von Mises yielding criterion and consists of three parts in which the biggest one locates in front of the crack tip. For Mode I crack, however, a similar plastic zone is obtained. Under the same magnitudes of applied stress, the plastic zone of Mode II crack is much larger than that of Mode I crack, and the plastic zone of a mixed-mode crack is mainly affected by the Mode II component. Dislocation-free zones exist around all types of crack tips, which have similar shapes as the corresponding plastic zones.