Direct formation of nano-scale dislocation loops during displacement cascade in BCC Fe studied by molecular dynamics simulation

In this work, the displacement cascades in bcc iron were simulated by molecular dynamics (MD). The formation of dislocation loops was found in cascade simulations when the energy of PKA (EPKA) was above 20 keV. For the first time, we reported the formation of <100> interstitial dislocation loops in cascade simulation of bcc iron under low EPKA, about 40 keV, much lower than that in Ref. 10. On the other hand, our results suggest that <100> loops all transformed into 1/2<111> loops within 200 ps. This will help us build a microscopic image and mechanism about the formation of interstitial dislocation loop.