Unveiling the effect of hydrostatic pressure on the passive films of the deformed titanium alloy

Abstract The protection of the passive film on the deformed Ti-6Al-4 V alloy depends on the film’s component and structure. Accordingly, the passive film resulting from hydrostatic pressure was systematically studied by electrochemical measurements and aberration-corrected TEM observations. The results exhibit that hydrostatic pressure leads to a thinning passive film and changes its components, which might be attributed to the accelerated film dissolution at hydrostatic pressure. With the synergic effect of hydrostatic pressure and tensile stress, the film’s protection is significantly reduced. In this condition, the metal/film interface presents an undulating structure, because the matrix dissolution is further facilitated by the cooperativity.