Abstract <p>Nickel-based single-crystal alloys reinforced by γ/γ' phases must withstand the combined effects of tension and friction during actual service, yet no studies on the associated coupled deformation mechanisms have been reported to date. This study innovatively establishes a coupled tensile-friction atomic-scale physical model, employing molecular dynamics simulations to elucidate the coupled damage mechanism at the atomic level. The results indicate that under coupled action, friction not only causes the material to reach its yield point earlier but also results in an interlaced stress distribution. During elastic deformation, γ/γ' phase boundaries impede force transmission, atomic displacement, and dislocation propagation, elevating friction forces while simultaneously driving dislocations to propagate along phase boundaries into the workpiece interior. During the plastic deformation stage, the phase boundaries and γ′ phase—which provide strengthening—are prematurely disrupted by tensile stress, causing the internal structure to become “relaxed.” This leads to the sinking of the grinding balls, resulting in a significant increase in friction force and friction coefficient. Furthermore, under coupled operating conditions, the γ′ phase generates substantial heat due to damage, resulting in temperatures higher than those of the γ phase, which benefits from superior thermal conductivity and heat dissipation within the interstitial structure. The phase boundary exhibits both high thermal conductivity and stress/atomic diffusion regulation capabilities, with this effect gradually diminishing as tensile-friction damage accumulates.</p> Graphical abstract <p></p>