Atmospheric Corrosion of Stainless Steels in Kuwait

Abstract The current paper presents the results of a one year atmospheric exposure of four stainless steels (SSs) in Kuwait. Flat panels of SSs types UNS S31603, UNS S13895, UNS S31803 and UNS S32101 having various surface finishing conditions were exposed to the atmosphere at five sites. In addition, welded and U-bend panels of UNS S31603 were exposed to the atmosphere at the five sites. Time of wetness (TOW) and chloride deposition rates were measured. The atmospheric corrosivity of the five sites was specified according to ISO 9223 standard. Based on TOW measurements, the atmosphere corrosivity is in the range of low to medium, while based on the chloride deposition rate, the atmosphere corrosivity is in the range of low to high depending upon the closeness of the site to the sea. The panels of SSs were examined visually as well as using optical and scanning electron microscopy. The degree of corrosion attack on the SSs panels varied with the changes in micro climate, surface roughness, and the type of SS, with the welded panels showing the highest degree of corrosion attack. With regard to alloy type, the ranking accurately reflected the molybdenum content with UNS S31803 SS performing better than UNS S31603L, UNS S13895, and UNS S32101 SSs.