347/347H is columbium stabilized austenitic stainless steel with good general corrosion resistance and somewhat better resistance in strong oxidizing conditions than the 321 grade. It has excellent resistance to intergranular corrosion after exposure to temperatures in the chromium carbide precipitation range of 800 1500F (427 816C). The alloy has good oxidation resistance and creep strength to 1500F (816C). It also possesses good low temperature toughness. The H designation indicates higher carbon (0.04 0.10) developed for enhanced creep resistance and for higher strength at temperatures above 1000F (537C). The carbon content of the material enables dual certification listed as 347/347H. The 347 alloy cannot be hardened by heat treatment, only by cold working. It can be easily welded and processed by standard shop fabrication practices. This material is ideally suited for Aerospace, Chemical Processing, Food Processing, Petroleum Refining, Pharmaceutical Production and Waste Heat Recovery. (UNS S34700 & UNS S3409)
