Effect of streaming water vapor on the corrosion behavior of Ti60 alloy under a solid NaCl deposit in water vapor at 600 °C

Abstract

The corrosion behavior of Ti60 alloy coated with solid NaCl layer in dry O2 and humid O2 (30.8 vol.% H2O) environments at 600 °C have been investigated. The isotopic tracing of 18O showed involvement of H2O in both the outer corrosion layer (OCL) and the inner corrosion layer (ICL). Theoretical calculations revealed that H2O provided 14% and 21% of the oxygen required for the formation of the outer and inner corrosion layers, respectively. Detailed analysis of corrosion products revealed that H2O enhanced the reaction of solid NaCl and TiO2 to form Na4Ti5O12 and promoted the crystallinity of corrosion products.