904L is a 'super austenitic stainless steel' specifically designed for harsh corrosive environments. It achieves corrosion resistance far exceeding that of ordinary stainless steels (such as 316L) through a formula with high nickel, high molybdenum, and added copper.
⚙️ Core Properties
· Exceptional Acid Resistance: Originally developed for resistance to dilute sulfuric acid, it performs excellently in sulfuric acid of all concentrations below 70°C; it also exhibits excellent resistance to organic acids such as phosphoric and acetic acid.
· Chloride Ion Corrosion Resistance: The combination of high nickel and high molybdenum provides outstanding resistance to pitting and crevice corrosion in chloride-containing environments (e.g., seawater).
· Stress Corrosion Resistance: With 25% high nickel content, the risk of stress corrosion cracking in chloride environments is significantly reduced, an area where 316L is a weakness.
· Intergranular Corrosion Resistance: With extremely low carbon content (≤0.02%), common intergranular corrosion issues after welding are generally not a concern.
· Key Performance Parameters: Density approximately 8.0-8.24 g/cm³, Tensile Strength ≥490 MPa, Yield Strength ≥216 MPa, Elongation ≥35%.