Long-Term Atmospheric Corrosion Behavior of Various Grades of Stainless Steel in Rural, Industrial, and Marine Environments

Abstract

Stainless Steels have been used in outdoor applications for many years. The classic example is the roof of the Chrysler Building in New York City that was constructed in 1926; it has been cleaned only once (in 1961) to remove surface deposits and restore its original gleam. Architecture, industry, and transportation (land, air, water, and space) all utilize stainless steels, and the list of components in each is endless. Eleven grades of stainless steel were evaluated after 29 years of exposure at two ASTM test sites: the rural atmosphere at State College, PA and the industrial atmosphere at Newark/Kearny, NJ. Previous evaluation of these same materials from the Kure Beach, NC 25- and 250-m marine sites have been reported and are referenced in this paper. The alloys evaluated include 200, 300, and 400 series stainless steels. This paper dwells on results from the rural and industrial sites, but summarizes alloy corrosion behavior from the mildest rural atmosphere to the most severe marine environment. All materials at each site had the same general appearance, and no significant corrosion was evident. In the rural atmosphere, all stainless steel surfaces remained virtually unchanged after 29 years of exposure. In the industrial atmosphere, all alloy surfaces were dark brown to black in color, resulting from the deposit of industrial airborne particles. These deposits could be removed by brisk rubbing with a wet cloth and nonabrasive cleanser, nearly returning the surfaces to their original appearance. No evidence of stress corrosion cracking was found around any welds or Erichsen cups. Mechanical properties of all alloys were unaffected by these long exposures.