UNS S21800 / ALLOY 218 / NITRONIC® 60
MATERIAL DESCRIPTION FOR UNS S21800 / ALLOY 218 / NITRONIC® 60
NITRONIC® 60 is silicon/manganese alloyed austenitic stainless steel with double yield strength of AISI 304 material. The increased silicon and manganese level inhibit wear, galling and fretting and makes the alloy fit for temperatures up to 1000°C. General corrosion resistance is between AISI 304 and 316. It offers better chloride pitting resistance, stress corrosion cracking resistance and crevice corrosion resistance than AISI 316L in laboratory conditions.
Applications
Applications using NITRONIC® 60 are valve stems, seats and trim, fastening systems, screening, pins, bushings and roller bearings, pump shafts and rings. Other uses include wear plates, rails guides, and bridge pins. This alloy provides a significant lower cost way to fight wear and galling compared to Nickel or Cobalt based alloys.
Heat Treatment
Annealed at 1066°C followed by water quenching.
Chemical composition
| Weight % | C | Si | Mn | S | P | Cr | Ni | Mo | N |
| Min. | 3,50 | 7,00 | 16,00 | 8,00 | 0,08 | ||||
| Max. | 0,10 | 4,50 | 9,00 | 0,030 | 0,060 | 18,00 | 9,00 | 0,75 | 0,18 |
Product Standards: ASTM A276, ASTM A479
Mechanical properties
| Yield strength Rp0.2, MPa |
Tensile Strength Rm, MPa |
Elongation [%] |
Hardness [HB] |
Impact, Charpy-V, -196ºC [J] |
|
| BAR | ≥ 345 | ≥ 655 | 35 | ≤ 241 | 150 |
| Typical | 400 | 720 | 55 | 200 |
Round bar stock
| DIA | KG/M |
| 38,1 mm | 9.2 |
| 59 mm | 22. |
| 63,5 mm | 25.5 |
| 76,2 mm | 36.6 |
| 101,6 mm | 65.1 |
Equivalent standards
- UNS S21800
- Nitronic® 60