Molecular dynamics simulation of radiation defect evolution mechanism of NiFe-graphene nanocomposite

Atomistic simulations were applied to investigate the coupling effect of the chemical complexity of single-phase concentrated solid solution alloys (SP-CSAs) and the defect-sink effects of graphene/CSA interfaces. The radiation-induced defect evolution and radiation resistance of NiFe-graphene (NiFeGr) nanocomposite were studied via energy calculation, cascade simulation, and defect insertion method. Results show that the interface acts as a defect trap to absorb interstitials and promote the migration of point defects toward the interface. The inherent effect of the CSAs promotes defect recombination, which significantly reduces the number of residual defects. At the same time, the concentrated solid solution alloy as matrix can effectively promote the strengthening of the interface. The combination of the two effects causes no obvious temperature effect of the radiation damage, but the material still shows good radiation resistance at high temperature. Therefore, the NiFeGr nanocomposite with synergy of concentrated solid solution alloy as a matrix and defect-sink effects from graphene interfaces shows good radiation resistance and broad application prospect in nuclear engineering materials.