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 dis location but also a jogged dislocation was chosen for the calculation of the interaction. In fee metal, the calculation was made for the int eraction between an extended dislocation and point defects. The effect ive interaction range, L, was determined for all the cases, and from t hese values the so-called bias factor was obtained as 55 and 19% for f ee (Au) and bcc (Fe) metals, respectively in the case of a straight di slocation. Almost no difference for this range L was seen between a di slocation without a jog and that with a jog. However, sink efficiency is considered to be higher for a jogged dislocation than a straight on e. A comparatively small bias factor, about 8%, was obtained for the c ase of a dislocation loop and point defects in the fee lattice.