Special alloys / UNS N06059
Alloy 59 is a high-purity nickel-chromium-molybdenum alloy with very low iron, offering among the highest resistance to pitting and crevice corrosion of the C-type alloys in both oxidising and reducing media.
- UNS N06059
- W.Nr. 2.4605
- Spec ASTM B575
- Density 8.6 g/cm³
Also known as / equivalents
| System | Designation |
|---|---|
| UNS | N06059 |
| W.Nr. | 2.4605 |
| EN | NiCr23Mo16Al |
| Also known as | Nicrofer 5923hMo, 2.4605, NiCr23Mo16Al |
Chemical composition
| Element | Min % | Max % |
|---|---|---|
| Ni | Bal. | — |
| Cr | 22.0 | 24.0 |
| Mo | 15.0 | 16.5 |
| Fe | — | 1.5 |
| Al | 0.1 | 0.4 |
| Co | — | 0.3 |
| C | — | 0.010 |
| Mn | — | 0.5 |
| Si | — | 0.10 |
| P | — | 0.015 |
| S | — | 0.010 |
| Cu | — | 0.50 |
Mechanical properties
| Property | Value |
|---|---|
| Tensile strength (min) | 690 MPa (100.1 ksi) |
| Yield strength, 0.2% offset (min) | 310 MPa (45.0 ksi) |
| Elongation in 50 mm (min) | 45 % |
Physical properties
| Property | Metric | Imperial |
|---|---|---|
| Density | 8.6 g/cm³ | 0.311 lb/in³ |
| Magnetic response | Non-magnetic | — |
Available forms & specifications
| Form | Specification | Size range |
|---|---|---|
| Sheets & plates | ASTM B575 (Alloy 59), B625 (926), B688 / A240 (AL-6XN), ASTM F30 (Nilo) | 0.3 mm – 6 mm |
| Pipe & tube | ASTM B619 / B622 (Alloy 59), B673 / B674 / B677 (926), B675 / B676 / B690 (AL-6XN) | 1/8" – 24" NB |
| Bars & rods | ASTM B574 (Alloy 59), B649 (926), B691 (AL-6XN) | 3 mm – 500 mm |
| Flanges & forgings | ASTM B564, B462 | 1/2" – 48" NB (larger on request) |
Corrosion & temperature resistance
Alloy 59, 926 and AL-6XN offer very high pitting and crevice resistance in chloride media; Nilo alloys are chosen for dimensional stability rather than corrosion resistance.
Applications
Alloy 59: FGD, chemical process, seawater. Glass-to-metal and ceramic-to-metal seals, lead frames and thermostat bimetals (Nilo); seawater cooling, desalination, FGD and chemical process equipment (59, 926, AL-6XN).
Alloy 59 vs Hastelloy® C-276
| Alloy 59 | Hastelloy® C-276 | |
|---|---|---|
| UNS | N06059 | N10276 |
| Key property | Very high pitting resistance | Most versatile corrosion-resistant alloy |
| Typical use | FGD, chemical process, seawater | FGD, chemical reactors, pulp bleaching |
| Cr (wt %) | 22.0–24.0 | 14.5–16.5 |
| Ni (wt %) | Bal. | Bal. |
| Mo (wt %) | 15.0–16.5 | 15.0–17.0 |
| C (wt %) | ≤ 0.010 | ≤ 0.010 |
| Tensile / yield (min, MPa) | 690 / 310 | 690 / 283 |
Frequently asked questions
What is the UNS number of Alloy 59?
Alloy 59 is designated UNS N06059 (W.Nr. 2.4605, EN NiCr23Mo16Al).
What is Alloy 59 used for?
Very high pitting resistance. Typical uses: fgd, chemical process, seawater.
Is Alloy 59 magnetic?
Non-magnetic.
In which forms can I buy Alloy 59 from Rajkamal Metals?
Coils & Strips, Sheets & Plates, Pipes & Tubes, Round Bars & Rods, Flanges, Buttweld Fittings, Socket Weld & Threaded Fittings. Sizes as per standard; other sizes on request.
Do you supply a Mill Test Certificate with Alloy 59?
Yes. Actual values are given in the Mill Test Certificate (EN 10204 3.1) supplied with each order.
What is the difference between Alloy 59 and Hastelloy® C-276?
Alloy 59: very high pitting resistance. Hastelloy® C-276: most versatile corrosion-resistant alloy. See the comparison table on this page.
Last updated: 30 October 2026. Grade names identify the supply range; designations are not engineering equivalents. Availability, make, origin and documentation are confirmed at quotation.
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