Grade 904L / 1.4539 / UNS N08904 

 

Grade 904L / X1NiCrMoCu25-20-5 / Z2CNDU25.20 / F904L / 904S13 / SS 2562 to ASTM B649 / ASME SB649 & NACE MR01-75 / ISO 15156 (Brands - URANUS B6™ / VLX904™ / AL-904L™ / CRONIFER 1925™ / 2RK65™) stainless steel is a non-stabilized austenitic stainless steel with low carbon content. This high alloy stainless steel is added with copper to improve its resistance to strong reducing acids, such as sulphuric acid. The steel is also resistant to stress corrosion cracking and crevice corrosion. Grade 904L 1.4539 UNS N08904 X1NiCrMoCu25-20-5 904S13 is non-magnetic, and offers excellent formability, toughness and weld ability. Corrosion Resistance Grade 904L / X1NiCrMoCu25-20-5 / Z2CNDU25.20 / F904L / 904S13 / SS 2562 to ASTM B649 / ASME SB649 & NACE MR01-75 / ISO 15156 (Brands - URANUS B6™ / VLX904™ / AL-904L™ / CRONIFER 1925™ / 2RK65™) stainless steels have excellent resistance to warm seawater and chloride attack. The high resistance of grade 904L / X1NiCrMoCu25-20-5 / Z2CNDU25.20 / 904S13 / SS 2562 / NACE MR01-75 / ISO 15156 against stress corrosion cracking is due to the presence of high amounts of nickel in its composition. Moreover, the addition of copper to these grades develops resistance to sulphuric acid and other reducing agents in both aggressive and mild conditions. Applications some of the major applications of grade 904L stainless steels include: Wiring in electrostatic precipitators / Oil refinery components / Seawater cooling devices / Gas scrubbing plants / Pulp and paper processing industries / Phosphoric and sulphuric acid processing plants / Production and transport of sulphuric acid / Metal pickling in sulphuric acid / Production and concentration of phosphoric acid / Use in seawater, brackish water, condensers, heat exchangers / Paper and allied industries / Gas washing / Chemical and pharmaceutical industries. DESCRIPTION Grade 904L / X1NiCrMoCu25-20-5 / Z2CNDU25.20 / F904L / 904S13 / SS 2562 to ASTM B649 / ASME SB649 & NACE MR01-75 / ISO 15156 (Brands - URANUS B6™ / VLX904™ / AL-904L™ / CRONIFER 1925™ / 2RK65™) is a high-alloy austenitic stainless steel with low carbon content. The grade is intended for use under severe corrosive conditions. It has been application proved over many years and was originally developed to resist corrosion in dilute sulphuric acid. It is standardized and approved for pressure vessel use in several countries. Structurally, 904L is fully austenitic and is less sensitive to precipitation ferrite and sigma phases than conventional austenitic grades with high molybdenum content. Characteristically, due to the combination of relatively high contents of chromium, nickel, molybdenum and copper 904L has good resistance to general corrosion, particularly in sulphuric and phosphoric conditions. DESIGN FEATURES Good resistance to pitting and crevice corrosion / Very good resistance to stress corrosion cracking / Good resistance to intergranular corrosion / Good formability and weld ability / Maximum service temperatures of 450 deg.C. (824 deg.F). Most common fusion and resistance methods may be employed. For maximum corrosion resistance, it is recommended to use filler metals of equal or higher alloy content. Hot work should proceed after uniform heating to 2000-2200 F. Do not work the material at less than 1800 F. full annealing should follow any hot work to retain maximum ductility and corrosion resistance. Grade 904L / X1NiCrMoCu25-20-5 / Z2CNDU25.20 / F904L / 904S13 / SS 2562 to ASTM B649 / ASME SB649 & NACE MR01-75 / ISO 15156 (Brands - URANUS B6™ / VLX904™ / AL-904L™ / CRONIFER 1925™ / 2RK65™) Although higher forces are required, 904L will respond in a similar fashion to other austenitic stainless steels like 304, 316 or 317. Most common operations can be successfully performed. 1920-1990 F (1050-1090 C), rapid cooling. This alloy does not respond to heat treatment. It may only be hardened by cold reduction. Excellent stability against pitting corrosion, stress corrosion and intergranular corrosion.