Performance of different microstructure on electrochemical behaviors of laser solid formed Ti–6Al–4V alloy in NaCl solution

The effect of different heat treatment on electrochemical behavior of laser solid formed Ti–6Al–4V alloy in 15 wt% NaCl solution was systematically investigated. Microstructure characteristics including phase volume fractions and elemental segregation after different heat treatment and the electrochemical anodic behaviors related to the polarization tests and passivation process were analyzed. The electrochemical results show that the annealed sample has slightly better corrosion resistance owing to more uniform element distribution compared with solution treatment and aging samples. Different EIS results and defect concentrations between the passivation films formed on the two samples found that element distribution has significant effect on stability of the passivation films.