COMPUTER-SIMULATION OF THE BIAS FACTOR IN VOID SWELLING IN METALS

In order to obtain information on the bias factor in void swelling in metals, computer simulation in a model lattice has been performed for the interaction between a dislocation, or a dislocation loop and point defects in both fee (Au) and bcc (Fe) metals. Not only a straight dislocation but also a jogged dislocation was chosen for the calculation of the interaction. In fee metal, the calculation was made for the interaction between an extended dislocation and point defects. The effective interaction range, L, was determined for all the cases, and from these values the so-called bias factor was obtained as 55 and 19% for fee (Au) and bcc (Fe) metals, respectively in the case of a straight dislocation. Almost no difference for this range L was seen between a dislocation without a jog and that with a jog. However, sink efficiency is considered to be higher for a jogged dislocation than a straight one. A comparatively small bias factor, about 8%, was obtained for the case of a dislocation loop and point defects in the fee lattice.