Corrosion Resistant Alloys
NAS 254N
- JISSUS 836L
- UNSS32053
- DIN/ENー
Super Austenitic Stainless Steel
NAS 254N (SUS 836L, UNS S32053, ASME Code Case 2445-2) is a high corrosion resistance austenitic stainless steel with a high nickel, high chromium, high molybdenum alloy design, and provides excellent corrosion resistance in severe corrosion environments such as high temperature seawater. Depending on the environment, this stainless steel offers high economy combined with corrosion resistance comparable to that of Nickel alloy and pure titanium. Nippon Yakin supplies this product in plate, sheet and strip form.
| Chemical Composition | 23Cr-25Ni-5.5Mo-0.2N |
|---|---|
| Product shape |
 Coil Sheet Plate |
| Workability | The hot and cold workability of NAS 254N is basically the same as that of standard austenitic stainless steels such as Type 304, Type 316, etc. However, the fact that this is a high strength material must be considered in both cold and hot working. |
| Weldability | Various welding methods are applicable in the same manner as with the standard austenitic stainless steels, including shielded metal arc welding, TIG welding, and plasma welding. Alloy 276 welding consumable should be used. |
| Machinability | As a feature of high Ni stainless steels, although machining is difficult in comparison with the standard austenitic stainless steels, it is easier than with Ni-based alloys. A ultrahard tool should be used in machining if at all possible. It is also advisable to use a slower feed rate and deeper cutting depth. |
| Heat Treatment | Solution annealing of NAS 254N should be performed at the temperature range from 1080 to 1180℃ followed by being quenched in water or rapidly cooled by other means. (Conditions provided in ASTM A480/A480M) |
| Pickling | A mixture of nitric acid and hydrofluoric acid is used in pickling. However, due to the high corrosion resistance of NAS 254N, scale is somewhat difficult to remove in comparison with Type 304. Therefore, the material should be immersed in an alkaline solution before pickling, or if possible, shot blasting is extremely effective. |
| Applications | •Seawater environments: Marine structures, seawater desalination systems, heat exchangers using seawater, condenser tubes, etc. •Chemical plants: PC manufacturing plants, bis-phenol A manufacturing plants, carbon black manufacturing plants, etc. •Pulp and paper plants: Various types of bleaching systems, scrubbers, etc. •Medical and pharmaceutical product plants: Centrifugal separators, reaction tanks, etc. •Food product plants: Soy sauce fermentation tanks, salty mirin tanks, dressing manufacturing equipment, etc. •Pollution prevention systems: Thermal power plant flue gas desulfurization plants, etc. |