passivation

in electrochemical corrosion
https://doi.org/10.1351/goldbook.P04443
The process of transition from the active to the passive state by formation of the passivating @F02366@. Passivation is achieved by an anodic current which at the respective @E01956@ must be larger than the maximum current, or by the presence of an oxidized substance in the neighbouring solution which passivates by being reduced (passivator).
See also:
passive state
,
active state
Source:
PAC, 1989, 61, 19. (Electrochemical corrosion nomenclature (Recommendations 1988)) on page 21 [Terms] [Paper]