Molecular dynamics studies on interaction between a screw dislocation and a void in pure Fe, 2

Onitsuka, Takashi*; Okubo, Manabu*; Suzudo, Tomoaki   ; Fukumoto, Kenichi*

Reactor structural materials such as pressure vessels become brittle under neutron irradiation. It is widely known that a cause of such phenomenon could be formation of extended lattice defects under irradiation such as voids that become obstacles for dislocation motion, but we do not know the strength of these obstacles accurately enough for establishing a quantitative model. In the present study, we choose pure iron as a substitute of steel and numerically simulate the interaction between screw dislocation and a void using molecular dynamics method. Especially, we analyze the critical shear stress.