Cumulative damage function model for prediction of uniform corrosion rate of metals in atmospheric corrosive environment

Abstract

The main focus of the paper is on the development of a unified analytical model for predicting the rate of uniform corrosion for commonly used engineering metals exposed to the atmosphere. A cumulative damage function model is proposed on the presumption that the corrosion is primarily due to the presence of critical corrosive agents in the atmosphere. The model incorporates sensitivity factors to account for the corrosion sensitivity of the metal with respect to the critical corrosive agents and the presence of other corrosive agents. Predictions of the uniform corrosion rate of metallic structures made of iron, mild steel, carbon steel, and zinc are presented. Results predicted using the model are compared with the values expected for mild steel using the data available in the Corrosion Map of India.CEST/2153

Three years outdoor exposure of low carbon steel in Mauritius

“…It has generally been observed that rural and urban regions have lower corrosion rates than marine and industrial sites (de la Fuente et al, 2011). This is due to the fact that airborne salinity (Cole et al, 2003;Santana et al, 2001;Singh et al, 2008) in marine sites and sulphur dioxide level (Bhaskar et al, 2004;Lan et al, 2006) in industrial sites have been found to influence significantly the rate of atmospheric corrosion. Time of wetness (TOW), which depends on the relative humidity, is considered as another factor affecting atmospheric corrosion, especially in tropical humid climates (Veleva and Maldonado, 1998;Cai and Lyon, 2005).…”

Long term atmospheric corrosion in Mauritius

“…Rainfall is abundant, with an average of 2000 mm per year 1 and relative humidity is frequently above 80%. Since the principal exposure parameters influencing atmospheric corrosion for a given metal are moisture, temperature, contaminants in the environment and the methods used for corrosion control, 2 and carbon steel is corrosion prone, atmospheric corrosion is a serious problem for metallic structures in Mauritius. In fact, atmospheric corrosion causes a vast amount of damages in society and losses due to corrosion have been found to make a significant impact on the economy of many countries.…”

Atmospheric corrosion in Mauritius

“…Hence, the actual time during which the metal surface remains wet, that is, the time of wetness (TOW), can be very high. This high level of relative humidity coupled with a high level of airborne salinity can enhance the atmospheric corrosion effects, 3 and they are expected to contribute to the serious atmospheric corrosion problem actually prevailing in Mauritius. The present study was therefore performed in order to get a better insight into this problem.…”