Different corrosion behaviors between α and β phases of Ti6Al4V in fluoride-containing solutions: influence of alloying element Al

Abstract In this study, the different corrosion behaviors between α and β phases of Ti6Al4V in solutions with different NaF concentrations are investigated. When the NaF concentration changes from 0.15 to 0.20 M, α phases are more likely to suffer from corrosion than β phases. However, the formation of a repassive film makes α phases exhibit superior corrosion resistance than β phases as the NaF concentration reaches 0.50 M. The mechanism analysis reveals that the formation of a repassive film on the α phases depends on not only the Al content but also on the active dissolution rate of Ti.