原子尺度下FeCrAl合金辐照损伤效应OA

As a promising candidate material for nuclear fuel cladding,it is important to understand the damage characteristics of FeCrAl alloy under irradiation conditions.The cascade collision process of the alloy at different doses of irradiation damage were simulated using molecular dynamics(MD)method.The evolution characteristics of grain boundary(GB)atoms and amorphous phases were analyzed,and the spatial distribution of point defects and dislocations before and after irradiation were compared to reveal the mechanisms of the generation and evolution of irradiation induced defects.The results show that a large number of point defects and defect clusters were introduced during irradiation,and the higher the irradiation damage dose,the larger the number of clusters and the higher the defect cluster fraction;The point defects introduced by the irradiation preferred to aggregate at GBs,which lead to an increase in the fractions of GB and amorphous atoms.The thickness of GB increased at low doses without significant amorphization,while at high doses amorphous phases were formed with GB as the core,and the higher the dose,the higher the degree of amorphization.The irradiation also lead to the changes in the spatial distribution and overall density of dislocations,which was slightly higher after irradiation at low doses than in the absence of irradiation,but would significantly decrease with the increase of dose.