Atomic-scale study of the effect of γ/γ′-phase and interface on workpiece wear mechanism during reciprocating friction of nickel-based single crystal alloys

The impact of the gamma/gamma'-phase and interface on the frictional wear of nickel-based single-crystal alloys during reciprocating friction has been investigated through molecular dynamics simulations. The presence of the gamma/gamma' interface results in heightened friction, the transformation of large-displacement atoms into small-displacement atoms, and dislocation propagation downward along the interface. Furthermore, the gamma-phase exhibits a lower population of high-temperature atoms than the gamma'-phase and demonstrates superior cooling rates in contrast to the gamma'-phase. Additionally, abrasion marks in the gamma-phase are deeper than those observed in the gamma'-phase, with both phases displaying elastic recovery. As the number of friction cycles increases, the cooling rate of the gamma-phase continues to outperform that of the gamma'-phase. Moreover, the elastic recovery capacity of gamma '-phase remains relatively constant, whereas the elastic recovery capability of the gamma-phase gradually diminishes.