An Object Kinetic Monte Carlo Simulation for Defect Evolution of Neutron‐Irradiated Reactor Pressure Vessel Steels: Carbon Sensitive Study

Abstract

Herein, the defect evolution in the FeCMnNi model alloy is investigated by the gray‐alloy method in an object kinetic Monte Carlo (OKMC) model. Based on the parameters of the Fe–C system, the influence of Mn and Ni is implicitly considered, and the migration energy of mobile defects is modified. The number density of interstitial clusters and vacancy clusters in simulation has a good agreement with experimental results. The defect evolution features versus carbon and solutes concentration are also studied. The simulation results show that the number density of defect clusters increases with increasing carbon or solutes concentration. The average size of interstitial clusters decreases, while the average size of vacancy clusters is hardly affected by increasing impurity/solutes concentration. The defect features do not show a saturation tendency with increasing carbon/solutes concentrations. It also seems the influence of solutes concentration is more sensitive on defect features than carbon concentration in this FeCMnNi alloy.