Kowalczyk, J.; Madej, M.; Dzięgielewski, W.; Kulczycki, A.; Żółty, M.; Ozimina, D. Tribochemical Interactions between Graphene and ZDDP in Friction Tests for Uncoated and W-DLC-Coated HS6-5-2C Steel. Materials2021, 14, 3529.
Kowalczyk, J.; Madej, M.; Dzięgielewski, W.; Kulczycki, A.; Żółty, M.; Ozimina, D. Tribochemical Interactions between Graphene and ZDDP in Friction Tests for Uncoated and W-DLC-Coated HS6-5-2C Steel. Materials 2021, 14, 3529.
Kowalczyk, J.; Madej, M.; Dzięgielewski, W.; Kulczycki, A.; Żółty, M.; Ozimina, D. Tribochemical Interactions between Graphene and ZDDP in Friction Tests for Uncoated and W-DLC-Coated HS6-5-2C Steel. Materials2021, 14, 3529.
Kowalczyk, J.; Madej, M.; Dzięgielewski, W.; Kulczycki, A.; Żółty, M.; Ozimina, D. Tribochemical Interactions between Graphene and ZDDP in Friction Tests for Uncoated and W-DLC-Coated HS6-5-2C Steel. Materials 2021, 14, 3529.
Abstract
If a lubricant contains structures capable of conducting energy, reactions involving zinc dialkyldithiophosphate (ZDDP) may take place both very close to and away from the solid surfaces, with this indicating that ZDDP can be a highly effective anti-wear (AW) additive. The central thesis of this article is that the tribocatalytic effect is observed only when the energy emitted by the solids is transmitted by ordered molecular structures present in the lubricant, e.g., graphene. The friction tests were carried out for 100Cr6 steel balls in a sliding contact with uncoated or a:C-H-coated HS6-5-2C steel discs in the presence of polyalphaolefin 8 (PAO 8) as the lubricant, which was enhanced with graphene and/or ZDDP. There is sufficient evidence of the interactions occurring between ZDDP and graphene and their effects on the tribological performance of the system. It was also found that the higher the concentration of zinc in the wear area, the lower the wear. This was probably due to the energy transfer resulting from the catalytic decomposition of ZDDP molecules. Graphene, playing the role of the catalyst, contributed to that energy transfer.
Keywords
graphene; diamond-like carbon; zinc dialkyldithiophosphate; lubricant additive; surface layers of solid elements
Subject
Chemistry and Materials Science, Biomaterials
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
