Tribological properties and releasing behavior of solid lubricant WS2 in the dimples on cylinder liner surface of diesel engine

Modified WS2 by silane coupling agent were encapsulated in the dimples fabricated on the surface of cylinder liner samples by hot-pressing method. The tribological properties, anti-adhesion performance of the samples as well as the releasing behavior of modified WS2 in the dimples were tested by a reciprocating tribotester. Moreover, the anti-erosion performance of modified WS2 was examined by ultrasonic vibration test. The results indicate that the composite lubrication structure has good anti-friction and anti-adhesion effects. Furthermore, the release rate of WS2 in the dimples is decreased by 102.2% due to the introduction of silane coupling agent. Additionally, the synergistic effect among the dimples, the solid lubricant and the silane coupling agent can explain the anti-friction and sustained release mechanisms.