Tribological and mechanical behavior of tantalum and its compounds reinforced PEEK coatings for TKR

In biomedical applications, poly-ether-ether-ketone (PEEK) is capable of modifying traditional metal components, but still lacks strength and wear resistance. In this study, a series of soft-hard phase structure coatings with modified PEEK are produced by combining PEEK as the soft-antifriction phase, as well as tantalum (Ta), tantalum carbide (TaC), and tantalum nitride (TaN) nanoparticles as the hard-wear resistance phase. The coatings of a total knee replacement system were evaluated by finite element analysis (FEA). As a result, the reinforcement of nanoparticles has a significant impact on stress distribution and transfer, improving mechanical behavior and wear resistance, whereas TaC nanoparticles have the greatest ability to enhance these properties. The implant with the modified coating (PEEK/TaC) can be expected to reduce the stress of the Ti implant substrate by about 38.3 % compared to unmodified PEEK coating. Combined the experimental and simulated results showed that the modified coatings have the potential to enhance the lifespan of TKR Ti-based implants.