Temperature-dependent tribological behavior and interfacial mechanism of (SiTiAlNaCa)O multicomponent oxide glass coating

High-temperature forming of titanium alloys often suffers from inadequate lubrication at elevated temperatures, and glass lubricating coatings are among the main approaches to mitigate interfacial friction and wear while providing surface protection. A (SiTiAlNaCa)O multicomponent oxide glass (MCOG) coating was fabricated on Ti–6Al–4V (TC4) via slurry brushing and room-temperature drying, aiming to evaluate its oxidation resistance and tribological performance at high temperatures. Isothermal oxidation tests were conducted at 900 °C, and tribological behavior was investigated from 400 to 1000 °C. The coating reduced the mass gain after oxidation at 900 °C from 17.5 to 0.85 mg cm -2 . Interfacial reactions produced a layered Al 2 O 3 /Ti 5 Si 3 /Ti 3 Al structure, providing an additional diffusion barrier. The minimum wear rate was obtained at 800 °C, approximately 1.5 × 10 -5 mm 3 N -1 m -1 , where the softened glass formed a more continuous lubricating film and a tribochemical oxide film stabilized sliding. Abrasive wear dominated at 400-800 °C, whereas combined abrasive/adhesive wear occurred at 900-1000 °C. Overall, the MCOG coating simultaneously improved oxidation resistance and high-temperature wear performance, demonstrating its potential as a protective lubricating coating for titanium alloy forming.