Accelerated SCC Testing of Stainless Steels According to Corrosion Resistance Classes

The German Guidelines for stainless steel in buildings (Z.30.3-6) issued by the German Institute for Building Technology (DIBt) categorizevarious stainless steel grades into five corrosion resistance classes (CRCs). Only 21 frequently used grades are approved and assigned to these CRCs. To assign new or less commonly used materials, a large program of outdoor exposure tests and laboratory tests is required. The present paper shows theresults of stress corrosion cracking (SCC) tests that can distinguish between different CRCs. Slow strain rate tests (SSRT) were performedin various media and at different temperatures. CRC IV could be distinguished from CRC II and CRC III with a 31.3 % Cl - as MgCl2 solutionat 140 °C. CRC II and CRC III could be differentiated by testing in a 30% Cl - as MgCl2 solutionat 100 °C.