Effect of h-BN nanoparticles and dimple textures on the friction and wear performance of the marine grade stainless steel

Surface texturing has emerged as an effective strategy to improve the tribological performance of sliding components. This study examines the synergistic influence of micro-dimple textures and hexagonal boron nitride (h-BN) solid lubricant on the tribological behavior of marine-grade steel (AISI 316 L). Three textured surfaces with dimple densities of 5% (T-5), 9% (T-9), and 20% (T-20) were investigated. Among them, T-20 exhibited the highest oil spreading ability, with a contact angle of 36.1°, compared to 76.08° for the untextured surface (T-0). Under dry sliding conditions, the wear coefficient showed significant reductions compared to T-0: 52.7% for T-5, 44.1% for T-9, and 66.7% for T-20. In lubricated conditions, the T-20 surface combined with h-BN nanoparticles (T-20-L-BN) demonstrated the lowest average wear coefficient among all textured surfaces, achieving an impressive 97.3% reduction compared to T-0. The enhanced tribological performance is attributed to the synergistic effect of dimple textures and h-BN nanoparticles, where dimples improve lubricant retention and debris trapping, while h-BN facilitates the formation of a protective tribofilms. These results highlight that integrating optimized surface textures with solid lubricants significantly enhances wear resistance and friction behavior, offering promising applications in marine and engineering components.