Experimental and numerical evaluation of the mechanical properties of compacted wear debris layers formed between composite and steel surfaces in sliding contact

Microindentation experiments and non-linear FE contact analysis were used to study the hardness of a CF/PEEK (carbon fibre/polyetheretherketone) polymer composite material in the presence of a transfer film layer (TFL). The latter resulted from a sliding contact of the composite against a steel counterpart. The TFL plays an important role in the load transmission, and it therefore also affects the wear process. To study these mechanisms, requires reliable material data for the TFL. This study concentrates on TFL obtained at the beginning of a wear process on both components, i.e. the steel disk and the composite pin for two different fibre orientations relative to the sliding direction. Universal hardness values were evaluated from experimental load–depth profiles and their finite element analysis (FEA). The corresponding model contained contact elements that allowed prediction of the contact area, the contact pressure distribution, and the contact stresses and strains.