Fermonic® 60
Also known as Nitronic® 60, UNS S21800
Fermonic® 60 is a nitrogen-strengthened austenitic stainless steel with outstanding galling and wear resistance.
Fermonic® 60 (UNS S21800) is a nitrogen and silicon-strengthened austenitic stainless steel with outstanding resistance to galling and fretting wear, including self-mating galling resistance. It provides approximately twice the yield strength of Types 304 and 316 stainless steel, with excellent ductility and good corrosion resistance.
The combination of high strength, non-magnetic behaviour and exceptional galling resistance makes Fermonic® 60 a leading choice for valve stems, shafts, fasteners and any application where metal-to-metal contact under load occurs. Supplied annealed as standard.
We stock bar in the UK and USA. Plate, tube and fittings are available on enquiry; forgings and castings to order.
- Outstanding resistance to galling and fretting wear, including self-mating
- Approximately twice the yield strength of 304 and 316 stainless
- Excellent ductility and non-magnetic
- Good corrosion resistance comparable to Type 316
| Element | Min | Max |
|---|---|---|
| Iron (Fe) | Bal | |
| Chromium (Cr) | 16.0 | 17.0 |
| Nickel (Ni) | 8.0 | 8.5 |
| Manganese (Mn) | 7.5 | 8.5 |
| Silicon (Si) | 3.7 | 4.2 |
| Nitrogen (N) | 0.10 | 0.18 |
| Carbon (C) | 0.06 | 0.08 |
| Molybdenum (Mo) | - | 0.75 |
| Copper (Cu) | - | 0.75 |
| Niobium+Tantalum (Nb+Ta) | - | 0.10 |
| Titanium (Ti) | - | 0.05 |
| Tungsten (W) | - | 0.15 |
| Phosphorus (P) | - | 0.040 |
| Sulphur (S) | - | 0.030 |
| Aluminium (Al) | - | 0.02 |
| Property | Imperial | Metric |
|---|---|---|
| 0.2% Proof stress (min) | 55 ksi | 379 N/mm² |
| Tensile strength (min) | 105 ksi | 724 N/mm² |
| Elongation (5.65√S0 & 4D) | 35% | |
| Reduction of area | 55% | |
| Hardness (Brinell) | 241 max |
| Property | Imperial | Metric |
|---|---|---|
| 0.2% Proof stress (min) | 50 ksi | 345 N/mm² |
| Tensile strength (min) | 95 ksi | 655 N/mm² |
| Elongation (5.65√S0 & 4D) | 35% | |
| Reduction of area | 55% | |
| Hardness (Brinell) | 241 max |
| Property | Value |
|---|---|
| Density (kg/m³) | 7622 |
| Magnetic permeability (20°C) | 1.003 |
| Young's modulus (kN/mm²) | 181 |
| Specific electrical resistance, 20°C (µΩ.m) | 0.98 |
| Mean coefficient of thermal expansion, 20-100°C (m/m/°C) | 15.8 x 10⁻⁶ |
Equivalents & cross-references
Standard designations
- UNS
- S21800Unified Numbering System; also known as Alloy 218
- AMS
- 5848Bar, rod and wire
- ASTM
- A193Alloy-steel and stainless steel bolting A276Bar and shapes A479Bar and shapes
- ASME
- SA479Pressure vessel code
Fermonic® 60 is also designated UNS S21800, AMS 5848, ASTM A193, ASTM A276, ASTM A479 and ASME SA479.
Trade name equivalents
-
Nitronic 60
Cleveland-Cliffs (formerly AK Steel)
Nitronic 60 is a trade name of Cleveland-Cliffs (formerly AK Steel) for Fermonic® 60.
Common questions
What is Fermonic 60?
Fermonic 60 (Alloy 218) is a fully austenitic stainless steel covered by UNS S21800, AMS 5848, ASME SA479, ASTM A193, ASTM A276 and ASTM A479. It is supplied in the hot worked and annealed condition, with silicon and manganese additions giving superior wear, galling and fretting resistance and almost double the yield strength of Alloys 304/316. Langley Alloys stocks it as bar; plate, tube and fittings are available on enquiry, and forgings and castings are to order.
What is Fermonic 60 used for?
Fermonic 60 is used for fasteners, pins and bushings, wear rails and guides, roller bearings, marine shafts, pump components such as seals and wear rings, and valve stems, seats and trim. It is a cost-effective alternative to cobalt- and nickel-based alloys in wear and galling critical applications.
Why is Fermonic 60 chosen for galling and wear resistance?
Fermonic 60's silicon and manganese additions provide superior resistance to galling and associated wear mechanisms, making it preferable for applications with repeated movement or frequent assembly and disassembly, particularly against stainless steels. Its wear resistance of 2.8 mg per 1000 cycles is far better than annealed Alloy 304 (12.8) and 316L (12.5). It also retains mechanical properties up to 1200°C with good oxidation resistance and remains non-magnetic even after severe cold working.
How does Fermonic 60's corrosion resistance compare with Alloy 304 and 316?
Fermonic 60's general corrosion resistance sits between Alloy 304 and Alloy 316: it is generally better than Alloy 304 in most environments and approaches, but does not exceed, Alloy 316 for chloride pitting resistance, reflecting its Pitting Resistance Equivalent Number (PREN) of around 20. It offers good corrosion resistance across a wide variety of environments. Where higher pitting resistance is needed, a duplex or super duplex grade is the better choice.
What is Nitronic 60?
Nitronic 60 is a trade name used by Cleveland-Cliffs (formerly AK Steel) for UNS S21800 (Alloy 218), a fully austenitic stainless steel with excellent wear and galling resistance. Langley Alloys stocks this alloy as Fermonic® 60 to AMS 5848, ASTM A276, and ASTM A479.
What is Alloy 218 stainless steel?
Alloy 218 is another designation for UNS S21800, a fully austenitic nitrogen-containing stainless steel with high wear and galling resistance. Langley Alloys stocks this grade as Fermonic® 60, also known as Nitronic 60.
Is Fermonic 60 the same as Nitronic 60?
Yes. Fermonic® 60 is Langley Alloys' designation for UNS S21800 (Alloy 218), the same material sold by AK Steel as Nitronic 60. Both refer to a fully austenitic stainless steel meeting AMS 5848, ASTM A479, and ASTM A276.
What is the density of Fermonic 60?
Fermonic 60 has a density of approximately 7.62 g/cm³ (7620 kg/m³).
Is Fermonic 60 magnetic?
No. Fermonic 60 is an austenitic stainless steel and is non-magnetic (magnetic permeability around 1.003).
Datasheets
The galling-resistant stainless
Fermonic 60, also known as Nitronic 60, is a high-strength austenitic stainless steel with one stand-out property: outstanding resistance to galling and wear.
That makes it the natural choice for couplings, connectors, valve stems and other parts that must still move freely after long periods under load, without seizing, while keeping good corrosion resistance and strength.
Visit our YouTube channelFermonic® 60 is supplied in the annealed condition; bars are supplied peeled and polished with each bar ultrasonically tested and visually inspected.
Tools for this grade
Pitting & crevice resistance
Pitting & Crevice Resistance
Rank alloys by PREN and get an indicative pitting temperature for a chloride service. Pick a grade and a service temperature to see whether it has margin against pitting, or compare the range in the table below. A first-pass screen for chloride and seawater service.
| Grade | UNS | PREN | Indicative CPT | Relative pitting resistance |
|---|
Indicative screen, not a certified result. PREN ranks pitting resistance; the pitting temperature here is estimated from PREN (CPT ≈ 2.5 × PREN - 50), consistent with Langley's "PREN >40, CPT exceeding 50°C" for super duplex. Real critical pitting/crevice temperature depends on test method, product form, surface finish and service chemistry. Crevice corrosion starts well below the pitting temperature - allow a margin at gaskets, deposits and flange faces. Use certified data for design.
Request a quote
Tell us the grade, form and sizes.
Fast quotes from UK and US stock - bar, plate and pipe, cut and certified to spec.