HVAF Fabricated Ti3Si0.8Al0.2C2 coatings for Marine Applications

Corrosion, abrasion and biofouling in marine environments inflict significant economic losses and operational impacts upon vessels and offshore infrastructure. Carbide based MAX phase coatings could offer a promising solution due to their advantageous multiple properties including resistance to corrosion, wear and biofouling. This work aims to prepare MAX phase coatings with a composition of Ti3Si0.8Al0.2C2 by high-velocity air-fuel (HVAF) spraying technology, seeking to achieve multi-functional protection for the surface of devices in marine environment. The effects of varying spraying parameters on the microstructure, mechanical properties, friction and wear behaviour, electrochemical corrosion behaviour, and biofouling resistance of the Ti3Si0.8Al0.2C2 coating were systematically investigated. Results indicate that a smaller spraying distance and moderate propane pressure as HVAF parameters yield dense, low-oxidation, high-phase-purity MAX phase coatings. These coatings simultaneously enhance microhardness, friction-wear performance, and corrosion resistance. Concurrently, the coating has demonstrated a 95% antibacterial efficacy against E. coli after 32 h, indicating potential antibacterial and biofouling resistant properties. This study provides experimental data and theoretical basis for the application of HVAF-sprayed MAX phase coatings in complex marine environments, establishing an intrinsic relationship between HVAF process parameters, coating microstructure, and comprehensive protective performance.