Hastelloy X at a glance
- Designation: UNS N06002 / Werkstoff 2.4665, trade names Hastelloy X, Alloy X, Nicrofer 4722.
- Family: Ni-Cr-Fe-Mo solid-solution-strengthened nickel superalloy. It's a heat-resistant alloy, not a wet-corrosion CRA.
- Signature: high-temperature strength plus oxidation resistance in continuous service to ~1200 °C (2200 °F).
- Conformance: ASTM B435 / ASME SB-435 (plate, sheet, strip), ASTM B572 (rod), AMS 5536 (sheet/plate/strip), a mill test certificate comes with every order.
Nandini Steel keeps Hastelloy X ex-stock, ready for immediate dispatch. The plate is genuine mill material from nameable producers, backed by EN 10204 3.1/3.2 traceability. Want the broader picture on the Hastelloy family? Our nickel alloys reference lays it out.
Chemical composition (UNS N06002)
Hastelloy X gets its character from a balanced Ni-Cr-Fe matrix, with molybdenum and tungsten handling solid-solution strengthening and chromium holding oxidation at bay. The table below lists the N06002 element ranges per ASTM B435 / AMS 5536.
| Element | Symbol | Content (wt%) |
|---|---|---|
| Nickel | Ni | Balance (~47) |
| Chromium | Cr | 20.5 – 23.0 |
| Iron | Fe | 17.0 – 20.0 |
| Molybdenum | Mo | 8.0 – 10.0 |
| Cobalt | Co | 0.5 – 2.5 |
| Tungsten | W | 0.2 – 1.0 |
| Carbon | C | 0.05 – 0.15 |
| Manganese | Mn | 1.0 max |
| Silicon | Si | 1.0 max |
| Boron | B | 0.008 max |
| Phosphorus | P | 0.04 max |
| Sulfur | S | 0.03 max |
Role of Mo, Cr, Co and W
Molybdenum (8–10%) and tungsten do most of the work as solid-solution strengtheners, keeping strength up at red heat, a point where stainless grades start to fade. Chromium (20.5–23%) builds the protective oxide scale that gives Hastelloy X its oxidation resistance. Cobalt, meanwhile, props up the matrix and keeps the structure stable. Put together, these elements turn the alloy into a high-temperature workhorse, not a pitting-resistant acid alloy.
Mechanical properties (annealed, room temperature)
At room temperature, these values look typical for solution-annealed material. The alloy earns its place in combustion service because it holds its strength even when things get hot.
| Property | Typical value |
|---|---|
| Tensile strength | ~690 – 785 MPa (100 – 114 ksi) |
| Yield strength (0.2% offset) | ~310 – 360 MPa (45 – 52 ksi) |
| Elongation | ~35 – 45% |
| Hardness | ~90 HRB |
Physical properties
| Property | Value |
|---|---|
| Density | 8.22 g/cm³ |
| Melting range | ~1260 – 1355 °C |
| Thermal conductivity (RT) | ~9.1 W/m·K |
| Mean coefficient of thermal expansion (20–100 °C) | ~13.9 µm/m·°C |
| Elastic modulus | ~197 GPa |
High-temperature behavior
Hastelloy X earns its place when stainless grades like 310 or 321 run out of strength and oxidation life. A chromium-rich oxide scale stands up to high-temperature oxidation. The molybdenum-tungsten matrix, meanwhile, holds onto useful strength through continuous service up to about 1200 °C (2200 °F), and it handles carburizing and nitriding atmospheres well.
Be clear about what this grade does: it's a heat-resistant, oxidation-resistant superalloy, not a wet-acid or pitting-resistance (PREN) alloy. Aqueous acid, chlorides, sour service, if that's your duty, specify a wet-corrosion member of the family instead. Hastelloy C276 handles mixed oxidizing/reducing acids. Hastelloy C2000 is the one to reach for when you need the broadest acid versatility.
Equivalent grades and designations
| System | Designation |
|---|---|
| UNS | N06002 |
| Werkstoff (W.Nr) | 2.4665 |
| DIN | NiCr22Fe18Mo |
| AMS (sheet/plate/strip) | AMS 5536 |
| AMS (bar) | AMS 5754 |
| Trade names | Hastelloy X · Alloy X · Nicrofer 4722 |
Available forms and sizes
Nandini Steel keeps Hastelloy X on hand in both flat and long products, and fittings, flanges and fasteners are available too, so you can round out a full weld package. Everything sits ex-stock for immediate dispatch. Thickness, diameter and length on hand shift from heat to heat, though, so get a current stock list when you send your inquiry.
| Form | Typical standard |
|---|---|
| Plate / sheet / strip | ASTM B435 / ASME SB-435 · AMS 5536 |
| Round bar / rod | ASTM B572 · AMS 5754 |
| Pipe & tube | ASTM B619 / B622 / B626 |
| Pipe fittings | ASTM B366 |
| Forged fittings | ASME B16.11 / ASTM B564 |
| Flanges | ASME B16.5 / B16.47 |
| Fasteners | Matching N06002 chemistry |
Need a specific product form? We also hold Hastelloy round bar and Hastelloy pipe across the C-series and X.
Standards and specifications complied
Hastelloy X plate, sheet and strip are supplied to ASTM B435 / ASME SB-435 and AMS 5536; rod to ASTM B572 and AMS 5754; and welded pipe and tube to the ASTM B619, B622 and B626 group. Every release carries an EN 10204 3.1 (or 3.2 on request) mill test certificate confirming heat chemistry and mechanical results against the applicable standard.
Applications
Gas-turbine and aerospace combustion: combustor cans, transition ducts, afterburner and tailpipe components. This is the classic Hastelloy X application, where the alloy's balance of strength and oxidation resistance really pays off.
Industrial furnaces and heat treatment: furnace rolls, baffles, trays, muffles and other hardware that cycles through high temperatures in oxidizing atmospheres day after day.
Petrochemical high-temperature service: reformer and cracking-furnace components, along with other parts that see sustained heat beyond what heat-resistant stainless steels can practically handle. Hastelloy earns its keep here.
Testing and certification
Nandini Steel ships each heat with an EN 10204 3.1 mill test certificate (3.2 is available with third-party inspection on request), and it documents the N06002 chemistry and mechanical properties against ASTM B435 / AMS 5536. Positive material identification, or PMI, confirms the grade on the stock item itself. Heat and cast numbers keep traceability intact all the way from mill to dispatch.
The company holds ISO 9001:2015 certification as a stockist and has built a specialty in Hastelloy plates. Its material comes straight from producers like Aperam, Outokumpu, Jindal, POSCO, Nippon Steel and JFE, so the mill origin is never in question.
FAQ
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Request a quote
Nandini Steel keeps Hastelloy X (UNS N06002) ex-stock and ships right away to buyers around the world, backed by EN 10204 3.1/3.2 mill test certificates. Over 20+ years since 2003, the company has handled 307+ projects for 260+ clients across 36+ export countries. Send over your grade, form, dimensions and quantity and get live pricing. For an RFQ, call +91 22 43404600, message on WhatsApp at +91 99202 09184, or email reachus@nandinisteel.com.