Tribological behavior and mechanism of a self-lubricating coating with alternating soft and hard phases prepared horizontally along the substrate surface

Abstract Typically, self-lubricating coatings cannot concurrently possess the advantages of both soft coatings and hard coatings. To address this challenge and enhance coating performance, a novel structural coating was developed. This coating was fabricated by alternately depositing a soft layer and a hard layer along the horizontal direction on the substrate surface using electrospark deposition (ESD). The resulting coating exhibits excellent quality. Friction and wear behaviors of the coating were investigated under dry condition. The coating shows better comprehensive performance than single graphite coating and cemented carbide coating. Overall, the primary wear mechanism identified is adhesive wear accompanied by abrasive wear. In brief, this innovative coating combines exceptional wear resistance with effective lubricity, exerting the comprehensive performance of both hard and soft coatings.