Preparation and friction wear performance of ZrO2/MoS2 PEO composite coating

PEO composite coatings doped with ZrO 2 and MoS 2 particles were prepared on the surface of TC21 alloy using the PEO process. The morphologies and phase compositions of the coatings were analyzed using FE-SEM, TEM, XRD refinement and XPS. The tribological and self-lubricating properties of the coatings were investigated through fretting wear experiments. The results indicate co-doping reduced the friction coefficient by approximately 30 %. The co-doped coating demonstrated higher crystallinity, whereas the ZrO 2 coating contained a significant amount of amorphous material. The wear mechanisms of the coating included three-body abrasive, adhesive, and oxidative wear. The self-lubricating properties of the coating were derived from the presence of MoS₂ and the destruction and deformation of the coating surface during fretting wear.