New insight into the role of microscale residual stresses on initial corrosion behavior of Ti35 alloy

The effect of microscale residual stresses on the initial corrosion behavior of Ti35 alloys in boiling nitric acid solutions was investigated using a combination of electrochemical and immersion tests. The concentration of microscale residual stresses 48 h before corrosion accelerated the dissolution of Ti2+, Ti3+, and Ta5+, as determined by electrochemical impedance spectroscopy measurements and quantitative X-ray photoelectron spectroscopy analysis. After 48 h, the formation of oxide films with consistent compositions and contents (TiO2-51%, Ti2O3-47%, and Ta2O5-1.9%) prevented the corrosion medium from reaching the outer surface of the metal matrix, reducing the effect of residual stresses on the corrosion behavior.