904/904L stainless steel square pipe

904/904L Stainless Steel Square Pipe – Comprehensive Product Introduction       Product Identity   904/904L stainless-steel square pipe is a super-austenitic hollow section (UNS N08904 / EN 1.4539) designed for the most aggressive chloride, acid and high-temperature environments. The grade contains 19–23 % Cr, 23–28 % Ni, 4–5 % Mo and 1–2 % Cu, giving a PREN ≥ 34—double that of 316L. The ultra-low carbon (≤0.02 %) “904L” variant eliminates inter-granular corrosion during welding, while the straight-grade 904 (≤0.04 % C) offers marginally higher strength. Square sizes from 10 × 10 mm to 400 × 400 mm, wall 0.5–20 mm and mill lengths 1–12 m are produced to ASTM A554, EN 10219-2 and JIS G3466 in both seamless and welded (HFW, TIG) conditions. All sections are 100 % on-line UT/Eddy-current tested and supplied with EN 10204 3.1/3.2 mill certificates .   Mechanical & Corrosion Properties   - Room-temp yield 220–350 MPa, tensile 520–750 MPa, elongation ≥ 40 %, hardness ≤ 200 HB .   - C…