Tribological interactions between nitride coatings and Al₂O₃ counterparts: time-dependent friction mechanisms and thermo-mechanical response

Abstract In this study, CrN, AlCrN, TiN, and AlTiN coatings were deposited on 316 L stainless steel substrates and subsequently ground against Al 2 O 3 counterpart balls. Combined tribological tests and thermo-mechanical simulations revealed that friction instability strongly correlates with material transfer phenomena. Among the four investigated coatings, TiN demonstrated superior comprehensive performance, exhibiting the lowest average friction coefficient (0.2–0.3) and wear rate (2.33 × 10 −4 mm 3 /(N·m)). At the same time, numerical simulations confirmed it possessed minimal surface contact stress (1381 MPa), corresponding to the weakest material transfer behavior. In stark contrast, AlCrN showed the poorest friction-reducing and wear-resistant performance, along with the highest surface contact stress (1480 MPa), indicating the most severe material transfer phenomenon. Elemental analysis further supports the experimental observations, showing that the Cr content in the wear scars of AlCrN reaches as high as 82% under the 3 Hz condition, which is caused by the transfer of coating materials and the exposure of the Cr-containing substrate. Dominant wear mechanisms vary significantly among nitride coatings: CrN, AlCrN, and TiN coatings exhibit predominantly adhesive wear mechanisms involving material transfer and oxidative damage. In contrast, AlTiN coatings undergo complex interactions involving adhesion, micro-abrasion, and fatigue-induced microcracking.