Simulation analysis of dislocation emissions from crack tips of BCC iron

Suzudo, Tomoaki   ; Ebihara, Kenichi   ; Tsuru, Tomohito   ; Mori, Hideki*

BCC metals are used in various applications as structural materials, but they are known to become brittle in the low temperature range and their brittleness is accelerated by impurities such as hydrogen. It is thus desirable to model the phenomenon and predict it appropriately, but the mechanism is complicated and modeling is not easy. The authors have previously simulated penny-shaped cracks using the machine-learning empirical potential of Fe and found that crack growth on {110} planes is suppressed by dislocation emission, which is consistent with the experimental facts that no cracks are observed along this plane. In this study, we report a more detailed analysis of dislocation emission.