Abstract: Carbon Fiber (CF) reinforced polyetheretherketone (PEEK) composite is one of the most promising implant biomaterials used in orthopedics. In this article, unfilled PEEK and CF/PEEK specimens were prepared by vacuum hot pressing method, and their tribological properties were evaluated by sliding against a cobalt-chromium-molybdenum (Co-Cr-Mo) alloy block. The influences of mass fraction of carbon fibers in CF/PEEK and the surface oxidation treatment of carbon fibers were explored. The results showed that the water contact angles on the surfaces of CF/PEEK specimens decreased, indicating that their surface wettability was improved. The hardness value of CF/PEEK was significantly improved, the friction coefficients of CF/PEEK were effectively reduced and its wear resistance was enhanced compared with unfilled PEEK. The leading effect on CF/PEEK tribological properties was the mass fraction of CF, followed by surface oxidation of CF, and the calf serum solution had better lubricity than that of saline and deionized water.

Key words: surface oxidation treatment, lubrication, wear mechanism, CF/PEEK biocomposites