Pitting corrosion as a mixed system: coupled deterministic-probabilistic simulation of pit growth

7th AIC‐ICMR on Sciences and Engineering 2017

自然科学;工业技术

Ibrahim, Israr B.M.^1,2 ; Fonna, S.^2 ; Pidaparti, R.^1

College of Engineering, University of Georgia, Athens

GA

30622, United States^1

Corrosion and Computational Research Group (CCRG), Dept. of Mechanical and Industrial Engineering, Syiah Kuala University, Jl. Tgk. Syech Abdur Rauf No. 7, Darussalam, Banda Aceh

23111, Indonesia^2

关键词: Computational analysis;    Electrochemical activities;    General corrosion;    Polarization curves;    Polarization functions;    Probabilistic simulation;    Rate of corrosions;    Stochastic behavior;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/352/1/012018/pdf
DOI  :  10.1088/1757-899X/352/1/012018

来源: IOP

【 摘 要 】

Stochastic behavior of pitting corrosion poses a unique challenge in its computational analysis. However, it also stems from electrochemical activity causing general corrosion. In this paper, a framework for corrosion pit growth simulation based on the coupling of the Cellular Automaton (CA) and Boundary Element Methods (BEM) is presented. The framework assumes that pitting corrosion is controlled by electrochemical activity inside the pit cavity. The BEM provides the prediction of electrochemical activity given the geometrical data and polarization curves, while the CA is used to simulate the evolution of pit shapes based on electrochemical activity provided by BEM. To demonstrate the methodology, a sample case of local corrosion cells formed in pitting corrosion with varied dimensions and polarization functions is considered. Results show certain shapes tend to grow in certain types of environments. Some pit shapes appear to pose a higher risk by being potentially significant stress raisers or potentially increasing the rate of corrosion under the surface. Furthermore, these pits are comparable to commonly observed pit shapes in general corrosion environments.