SiCNO Ceramic Coatings on Surface‐Treated Ti‐6Al‐4V for Fretting Corrosion Protection

Fretting corrosion at the femoral stem‐neck and head interfaces critically limits hip implant longevity. This study evaluates polymer‐derived silicon oxycarbonitride (SiCNO) coatings on Ti‐6Al‐4V (Ti64) disks pretreated with acid–alkali and plasma processes. Diluted polysilazane (PSZ) preceramic precursors are pyrolyzed at 700–900 °C, forming 2–5 μm SiCNO films. Structural analysis reveals Ti 3 O layers at lower temperatures and rutile TiO 2 at 900 °C. Electrochemical testing shows 10 wt% PSZ at 900 °C achieved the highest corrosion potential (0.3522 V; lifespan 11.4 years), while 30 wt% PSZ at 700 °C maximizes the lifespan, 81.7 years; uncoated Ti64 exhibits minimal protection with a lifespan of 0.1 year. Hardness and reduced modulus increase with temperature and PSZ precursor content, peaking at 8.58 and 64.72 GPa. Elevated H/E (0.1325) and H 3 /E 2 (0.1506 GPa) ratios indicate enhanced wear and fracture resistance, though high‐temperature microcracks reduce corrosion protection. Overall, the SiCNO film with 20 wt% PSZ pyrolyzed at 800 °C provides an optimal balance of corrosion resistance and mechanical performance, demonstrating the promise of SiCNO coatings as durable protective layers for long‐term biomedical implant applications.