Tribological behavior of high-entropy alloy FeNiCrMn: a molecular dynamics simulation study

Co-free FeNiCrMn HEAs, as derivatives of the Cantor alloy, have attracted significant interest for their outstanding mechanical properties and cost-effectiveness. Exploring the fundamental mechanisms can facilitate the realization of improved composition design and enhanced modification of FeNiCrMn HEAs. Therefore, molecular dynamics simulations were employed to investigate the tribological behavior of the equiatomic FeNiCrMn high-entropy alloy, focusing on the effects of crystallographic orientation, sliding velocity, and indentation depth. The results reveal that the coefficient of friction (COF) remains relatively consistent across different crystallographic orientations, while the [11̄2] orientation exhibits lower dislocation density and more uniform atomic pile-up. Sliding velocity has a negligible impact on the COF, but higher velocities increase tangential forces due to strain-rate hardening. In contrast, deeper friction depths significantly elevate COF and subsurface damage, driven by enhanced dislocation nucleation and stress concentration. These results provide atomic-scale insights into the tribological mechanisms of FeNiCrMn HEA, offering guidance for its design in tribological environments.