## Abstract The kinetics of the pit nucleation in iron in borate buffer solution containing bromides and iodides (0.01 nβ0.5 n) has been investigated, and the results have been compared with those obtained for chloride solutions. It has been found that the critical pitting potential, E~cp~, decreas
Nucleation and Repassivation of Corrosion Pits for Pitting on Iron and Nickel
β Scribed by Dr. H.-H. Strehblow
- Publisher
- John Wiley and Sons
- Year
- 1976
- Tongue
- German
- Weight
- 996 KB
- Volume
- 27
- Category
- Article
- ISSN
- 0947-5117
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β¦ Synopsis
Abstract
Pit nucleation and repassivation on iron and nickel has been examined by potentiostatic transient measurements. Very short times for the nucleation of corrosion pits of some ms to some 100 ms for prepassivated specimens have been observed. Addition of picrate to the electrolyte can stop pit nucleation for well prepassivated specimens at all potentials completely, but cannot prevent the corrosion of already existing pits. The results are explained by the adsorptionβ and film breaking theory but give contradiction to the penetration mechanism. The repassivation of corrosion pits in an early stage of development takes Ξ T~r~ = 1 ms to some 100 ms according to the pitting time Ξ t~p~ and the pit current density. A relation Ξ T~r~ = k(Ξt~p~)^2^ has been found. The transport of the accumulated aggressive anions from the pit electrolyte to the bulk solution is postulated as the rate determining process for repassivation.
π SIMILAR VOLUMES
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