2022 Volume 71 Issue 5 Pages 158-164
The effects of chloride ion, acetate ion and Mo addition on the depassivation pH （pHd） of martensitic stainless steel were investigated using anodic polarization measurement and surface film analysis （XPS）. The increase of chloride ion concentration promoted partial destruction of the film and obscured the transition from active state to passive state. The increasing of acetate ion concentration increased the pHd and acted as a negative factor for passivation. It is considered that the addition of Mo lowered the pHd and promoted the formation of passivation film in a high-concentration acetic acid environment.
