Super austenitic, duplex and 300-series grades with tightly controlled chemistry.
Duplex and super austenitic stainless sit between the 300 series and the nickel alloys: much better chloride resistance than 316L, at a fraction of the cost of C-276. The practical limits are temperature — duplex should not run above about 300 °C — and welding, which needs the right filler and heat input.
We supply 2205 and 2507 forged and solution annealed, with ferrite content and hardness checked on the finished part.
| Grade | UNS | Typical service |
|---|---|---|
| 2205 | S31803 / S32205 / 1.4462 | General duplex: seawater, pulp mills, chemical tanks, 0–300 °C. |
| 2507 | S32750 / 1.4410 | Super duplex for higher chloride and pressure; seawater systems and FGD. |
| 254SMO | S31254 / 1.4547 | Super austenitic; chlorinated seawater, bleach and acid service. |
| 904L | N08904 / 1.4539 | Sulphuric and phosphoric acid; has been largely replaced by 254SMO and 6XN. |
| 310S | S31008 / 1.4845 | Oxidation resistance to 1,050 °C; furnace and radiant-tube parts. |
| 321 / 347H | S32100 / S34709 | Stabilised grades for elevated-temperature and intergranular-corrosion service. |
| 317L | S31703 / 1.4438 | Higher molybdenum than 316L for mild chloride environments. |
Quotes within one business day. Send grade, size, pressure class, face type and quantity — a drawing works better than a description.
