| Version | Summary | Created by | Modification | Content Size | Created at | Operation |
|---|---|---|---|---|---|---|
| 1 | Jack Zhong | -- | 200 | 2026-09-23 05:34:45 | | | |
| 2 | Jack Zhong | -10 word(s) | 190 | 2026-09-23 05:42:40 | | |
Corrosion mechanism is the sequence of electrochemical and chemical steps by which a metal in contact with an environment is converted back to an oxidised form, and identifying it means establishing which step limits the rate and which species take part. For a passive metal in a halide solution the mechanism of interest is the local breakdown of the passive film: chloride adsorbs, forms a soluble complex with the cation, and thins the film at a point until the bare metal dissolves fast enough to sustain a pit, and a model for that sequence was proposed for passive stainless steel in acid chloride [1]. In commercial stainless steel the site is rarely random, since non-metallic inclusions at the surface provide the initiation point [2]. Thin electrolyte layers behave differently from bulk solution, and pits under a chloride droplet grow under a transport constraint set by the droplet geometry [3]. Once a pit is established its growth can be treated as a dissolution kinetics problem [4]. Additively manufactured material adds a further variable, because its microstructure differs from the wrought alloy [5].