Friction and wear behavior of a precipitation-hardened equiatomic FeCrNi medium entropy alloy unraveled by molecular dynamics simulation

The precipitation-hardened medium/high entropy alloys (MEAs/HEAs) have a high potential for industrial applications due to their extraordinary properties, especially excellent wear resistance. However, friction and wear behavior of precipitation-hardened FeCrNi MEAs are largely unknown. Here, results of atomic simulations show that average normal force increases with the increasing precipitation radius, resulting in strong precipitation hardening. The precipitation within a certain height weaken hardening, owing to the reduction of normal force. The average tangential force for various precipitation heights is less compared to precipitation-free sample, and thus the friction coefficient decreases with the increase of precipitation radius. In addition, the surface roughness decreases with the increasing precipitation radius and height. The current work not only provides an insight into the atomic level friction and wear behavior of precipitation-hardened MEA, but also guides the development of advanced MEAs. Graphical abstract