Wear Mechanism of Superhard Tetrahedral Amorphous Carbon (ta‐C) Coatings for Biomedical Applications

Tetrahedral amorphous carbon (ta-C) coatings have the potential to protect biomedical implants from wear and increase their service life. This study elucidates biocompatibility, mechanical properties, adhesion, resistance of ta-C fabricated by physical vapor deposition on cobalt-chromium-molybdenum (CoCr) titanium (Ti64) alloys as well ultrahigh molecular weight polyethylene (UHMWPE). Satisfactory cytocompatibility is verified using contact angle surface tension measurements indirect direct cell testing. Scratch testing demonstrates excellent adhesion substrates confirmed nanoindentation, represent an up 13-fold 182-fold in hardness hard soft materials. In metal pin-on-UHMWPE disk sliding experiments under simulated body fluid lubrication, rates are reduced 48% (against CoCr) 73% Ti64) while pin factors 20 116 compared uncoated pairings. From optical laser scanning microscopy, Raman measurements, particle analyses, it shown that underlying remain protected. Nonetheless, focused ion beam electron microscopy revealed coating process-related thermally driven subductions tribologically induced near-surface fatigue, which can potentially constitute critical mechanisms.