
904L stainless steel, noto anche come UNS N08904 e W.Nr. 1.4539, is a high-alloy austenitic stainless steel with excellent corrosion resistance in aggressive environments. Its high levels of chromium, nickel, molybdenum, and copper make it highly resistant to sulfuric acid, chloride-induced pitting, and crevice corrosion.
904L is widely used in chemical processing, oil and gas, seawater systems, and pharmaceutical industries. It offers strong performance in acidic and chloride-rich environments, making it an ideal material for heat exchangers, piping, tanks, and components requiring durability and corrosion resistance.

| Elemento | % Present (in product form) |
| Carbonio (C) | 0.02 |
| Silicio (Si) | 0.7 |
| Manganese (Mn) | 2 |
| Phosphorous (P) | 0.03 |
| Zolfo (S) | 0.01 |
| Cromo (Cr) | 19.00 – 21.00 |
| Nichel (Ni) | 24.00 – 26.00 |
| Azoto (N) | 0.15 |
| Molibdeno (Mo) | 4.00 – 5.00 |
| Rame (Cu) | 1.20 – 2.00 |
| Ferro (Fe) | Bilancio |
| Calore specifico (0-100°C) | 450 | J.kg-1.°K-1 |
| Conducibilità termica | 11.5 | W.m -1.°K-1 |
| Espansione termica | 15.8 | μm/μm/°C |
| Modulo di elasticità | 190 | GPa |
| Resistività elettrica | 9.52 | Ohm-cm |
| Densità | 7.95 | g/cm³ |
| Temperamento | Ricotto | |
|---|---|---|
| Rm di trazione | 71 | ksi (min) |
| Rm di trazione | 490 | MPa (min) |
| R.p. 0,2% Rendimento | 32 | ksi (min) |
| R.p. 0,2% Rendimento | 220 | MPa (min) |
| Allungamento (2" o 4D gl) | 35 | % (min) |
| Seamless / Welded Pipe | ASTM A312 TP 904L |
| Seamless / Welded Tubing | ASTM A269 TP 904L |
| Barra / Barra | ASTM A276 / A479 TP 904L |
| Forgiatura | ASTM A182 F904L |
| Lastra / Piastra | ASTM A240 UNS N08904 |
| Welding Consumable | AWS A5.9 ER385 |
Standard product forms of 904L/N08904/1.4539 are pipe, tube, sheet, strip, plate, round bar, flat bar, forging stock, hexagon and wire. The products are available in a wide variety of sizes. Please contact us at [email protected] Per informazioni complete