Development of a Mathematical Model of Crevice Corrosion Propagation on NickelBase Alloys in Natural and Chlorinated Sea Water

摘要

Crevice corrosion initiation and propagation of nickel base alloys Inconel 625,Hastelloy C276 and Hastelloy 22 in sea water and chlorinated sea water has been studied by exposure tests, electrochemical studies, surface analysis and mathematical modelling. The initiation of attack has been shown to be a function of crevice geometry and surface composition and has been successfully predicted by the modelling route. A mechanism of propagation has been suggested which successfully predicts large differences in the corrosion rate of Inconel 625 for relatively small changes in crevice geometry and temperature. This work is being further developed under the project expansion.