Correlation of friction and wear across length scales for PEEK sliding against steel

The tribological properties of poly (ether ether ketone) (PEEK) were investigated at different length scales in order to elucidate commonalities and differences in friction and wear. To achieve this goal, the PEEK/steel tribo-system was studied by block-on-ring, block-on-disc, cone-on-disc, and cylinder-on-disc tests as well as by asperity scratching. For better comparability, asperities were prepared from the counter-body steel of the macroscopic experiments. Friction and wear properties were compared on the basis of the pv level. Friction coefficients in macro sliding can be related to the interfacial shear strength in asperity scratching by material's yield pressure. The study confirms that friction and wear of PEEK at different scales can be correlated, despite differences of characteristic velocity and pressure in different experiments.