FUNDAMENTAL STUDY TO EVALUATE MECHANICAL PROPERTY CHANGE ASSOCIATED TO DISLOCATION BEHAVIOR IN IRRADIATED AUSTENITIC STAINLESS STEELS BY INCORPORATING THERMAL FLUCTUATIONS

摘要

Molecular dynamics simulations were conducted with three interatomic potentials for face-centered cubic (FCC) metals with different stacking fault energies (SFEs), and the effect of the SFE on the dislocation behaviors was evaluated by incorporating thermal fluctuation. The separation distance between two partial dislocations fluctuated and was changed locally by thermal vibration, and the fluctuation increased with temperature. For a low-SFE metal, thermal vibration can hardly induce reversions into a perfect dislocation. This causes a characteristic morphology for interactions between a line dislocation and irradiation-induced defects for austenitic stainless steels.