Wear behaviour of hydrogenated DLC in a pin-on-disc model test under lubrication with different diesel fuel types

• The pin-on-disc model for the tribological investigations is proposed.
• The effects of load, speed and temperature on the DLC wear are investigated.
• Antiwear additives in diesel fuel increases the DLC wear rate.
• New mathematical wear laws for predicting the DLC wear volume are proposed.

The wear behaviour of hydrogenated diamond like-carbon (DLC) coating in DLC/steel tribological contact in a pin-on-disc model test under lubrication with two diesel fuels is presented in this work. The first diesel fuel was standard EN590 that contained ester-based antiwear additives. In contrast to EN590, the second diesel fuel, called GDK650, did not contain antiwear additives. It was experimentally observed that the antiwear additives are detrimental to the DLC. The effects of load, speed and temperature on the DLC and steel counterbody wear were investigated. Steel counterbody wear volume was found to be not affected by pressure, temperature, speed and lubricant, whereas the DLC-coating revealed correlation between the parameters and wear rate. Regarding the results of the tribological tests under both diesel lubrications, new mathematical wear laws were developed.