Long-Term Prediction of Atmospheric Corrosion Loss in Various Field Environments

Abstract

This paper deals with the prediction of long-term atmospheric corrosion in different field environments using the power-linear function. A method for the calculation of exponent n and stationary corrosion rate α in the power-linear function is proposed based on the 1- and 8-y corrosion loss results (C1 and C8) of the ISO CORRAG program. The response surface method and the artificial neural network methodology are used to obtain the accurate estimation of C1 and C8 in different locations using environmental variables. Considering the uncertainty of the model and the experimental data, the confidence intervals of n and α are also calculated. It is shown that the long-term predictions obtained by the proposed method coincide with the actual corrosion loss within ±30% relative error. The estimations for the range of the long-term corrosion loss are also reliable. The proposed method is helpful in extrapolating the knowledge of corrosion management to different field environments where corrosion data are not available.