Corrosion performance and mechanisms of tantalum coatings on 316 stainless-steel in subcritical aqueous solutions of NaCl and NaBr

The corrosion behavior of 316 stainless-steel with a tantalum (Ta-316) coating deposited using PVD technology was investigated in subcritical environments containing Cl− and Br− at 290 °C and 6 MPa. The corrosion rate of Ta-316 continuously decreased with increasing exposure time, demonstrating its high corrosion resistance. A thin film, mainly composed of Ta2O5, formed on the surface of the tantalum coating, preventing the diffusion of substrate elements. The corrosion process and mechanism of Ta-316 were also examined.