Molecular dynamic simulations evaluating the effect of the stacking fault energy on defect formations in face-centered cubic metals subjected to high-energy particle irradiation

Austenitic stainless steels, which are used as incore structural materials in light water reactors, characterized by an extremely low stacking fault energy (SFE) among face-centered cubic (FCC) metals. To evaluate the effects of SFE on defect formation under high-energy particle irradiation, molecular dynamics simulations were performed using interatomic potential sets for FCC metals with different SFEs and a primary knock-on atom (EPKA) 100 keV at 600 K. The results show that number residual defects is independent SFE. However, characteristics self-interstitial (SIA) clusters do depend For smaller than certain size, ratio glissile SIA decreases increases, similar to trend observed EPKA. larger clusters, can be detected only high EPKA, increases. These correspond static calculations, difference between Frank loop perfect (ΔEF-P) small In contrast, dependence ΔEF-P changes due shape restrictions stable loops. At temperature K, large vacancy faults EPKA = keV, resulting enhanced these lower SFEs. Furthermore, several loops, edges split into two partial dislocations faults, although largest EPKAs tetrahedrons.