Residual Stress Control for Prevention of Environmental Cracking of Stainless Steels

Requirements for residual stress control to prevent anodic stress-corrosion cracking and hydrogen-induced sulfide stress cracking may significantly affect the economics and scheduling of heat exchanger procurement.  This study reports microhardness, residual stress and environmental cracking test results for duplex stainless steels and austenitic stainless steels with residual stresses from heat exchanger fabrication operations including high surface area tube forming and hair-pin bend formation.  The ASTM E 837, ASTM G36 and NACE TM0177 methods are used to judge the risk of the as-fabricated conditions and the efficacy of residual stress control measures including solution annealing, stabilizing heat treatments, resistance-heating solution annealing and the imposition of residual compressive stress fields. Alloys tested include the austenitic AISI Types 304, 316 and 321 and duplex type 2205.