Corrosion Resistant Alloys
NAS NW22
- JISNW 6022
- UNSN06022
- DIN/EN2.4602
, comparable to Hastelloy® C-22® Alloy
NAS NW22 is a Ni-Cr-Mo alloy with excellent corrosion resistance. This alloy provides excellent pitting corrosion resistance, crevice corrosion resistance, and stress corrosion cracking resistance in both oxidizing and reducing environments, and is widely used as a material under severe environments such as flue gas desulfurization plants, papermaking processes, waste treatment processes, etc. Nippon Yakin supplies this product in plate, sheet and strip forms.
*Hastelloy and C-22 are registered trademarks of Haynes International, Inc.| Chemical Composition | 57Ni-21Cr-14Mo-3W-4Fe |
|---|---|
| Product shape |
 Coil Sheet Plate |
| Workability | Because the high-temperature strength of NAS NW22 is extremely higher than that of Type 304, care is required when hot working. The cold workability of NAS NW22 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 cold working. |
| Weldability | In welding, it is possible to apply ordinary welding methods in the same manner as with stainless steels. Matching composition welding consumables should be used. Post-weld heat treatment is not required. |
| Heat Treatment | Solution annealing of NAS NW22 is normally performed at the temperature range from 1150 to 1170℃ followed by being quenched in water or rapidly cooled by other means. |
| Pickling | A mixture of nitric acid and fluoric acid is used in pickling. However, because descaling is somewhat difficult in comparison with Type 304, alkali immersion before acid pickling, and if possible, shot blasting are extremely effective. |
| Applications | Pharmaceutical plants, semiconductor manufacturing equipment, various types of chemical plants, flue gas desulfurization plants |