Alloy 904L (UNS N08904) is a superaustenitic stainless steel with moderate to high corrosion resistance in a variety of process conditions. The combination of a high chromium and nickel content, along with molybdenum and copper additives, ensures good to exceptional corrosion resistance. With its highly alloyed chemistry — 25 percent nickel and 4.5 percent molybdenum — 904L offers excellent resistance to chloride stress corrosion cracking, pitting, and general corrosion, outperforming 316L and 317L molybdenum-enhanced stainless steels. Initially, alloy 904L was designed to endure situations including dilute sulfuric acid. It is also resistant to many organic acids and other inorganic acids, such as hot phosphoric acid. Welding and fabricating Alloy 904L is simple using typical shop fabrication procedures.