Temperature dependence of energy dissipation during nanoscale wear of AISI 304L stainless steel

Abstract

In the sliding process, mechanical work is widely considered to be dissipated in the form of heat. The dissipation of frictional energy, especially in scenarios involving material wear at various initial temperatures, needs further exploration. This work aims to evaluate energy dissipation during sliding wear of AISI 304L stainless steel at different initial temperatures through a combination of theoretical and experimental approaches. Molecular dynamics (MD) simulation reveals that the mechanical work decreases with the initial temperature due to the thermal softening effect. The mechanical work is converted into total energy (including internal energy and strain energy) and frictional heat. A peak value is observed on the frictional heat-initial temperature curve due to the trade-off between mechanical work and the change in total energy. When the workpiece temperature exceeds a critical temperature, the dynamic recovery dominates, and the strain energy decreases due to the reduction in dislocations and twinning. The dynamic evolution of dislocations is further experimentally verified by measuring the hardness of AISI 304L stainless steel with different scratching times. The present work contributes to a deeper understanding of energy dissipation in the wear process and lays a theoretical foundation for optimizing energy utilization in tribological systems.