“…However, there have been only a few reports to date, on the effects of proton irradiation on the tribological and wear properties of steel. While there are several reports on proton-irradiated stainless steel [18,19,20,21,22,23], they mostly focus on the effects of proton irradiation on the microstructures and properties of austenitic or ferritic steels that are used in the nuclear industry. Results on the tribological and wear properties of AISI 420 steel after tempering and proton irradiation are rarely reported.…”