904L is a high-alloy austenitic stainless-steel with little carbon content. The quality is meant for use under serious corrosive conditions. It had been application proven over several years and was initially designed to withstand corrosion in dilute sulfuric acid. It will be standardized and also authorized for pressure vessel utilize in many nations. Structurally, 904L is completely austenitic it is much less too sensitive to precipitation ferrite and also sigma phases compared to conventional austenitic grades with higher molybdenum content. Characteristically, because of the mixture of relatively higher contents of chromium, nickel, molybdenum and copper 904L provides high-quality resistance to basic corrosion, especially in sulfuric and also phosphoric conditions.

The addition of copper to this quality provides it corrosion protected properties more advanced than the conventional chrome nickel stainless steel, specifically to sulphuric, phosphoric and also acetic acids. But, there is certainly minimal use with hydrochloric acids. This also provides an excellent protection to pitting in chloride solutions, an excellent resistance to both crevice and then stress corrosion cracking. Alloy 904L performs much better than other austenitic stainless steel steels because of the much higher alloying of nickel as well as molybdenum.