Microstructure, mechanical properties and tribological behavior of tribofilm generated from natural serpentine mineral powders as lubricant additive

► The chemical and physical structure of tribofilm formed by serpentine was studied. ► Load-partial-unload nano-indentations were performed on the tribofilm generated. ► Stribeck tests for mineral base oil were conducted on the tribofilm. ► A phenomenological model was developed based on the experimental results.