UNS N06002 (Hastelloy X) Open-Die Forgings
UNS N06002 is a nickel-chromium-iron-molybdenum superalloy, nominally 47% Ni, 22% Cr, 18% Fe and 9% Mo. It is strengthened by solid solution and stays oxidation resistant in air to about 1204 °C (2200 °F). UNS N06002 is the UNS designation for the alloy known as Hastelloy X, also called Alloy X, W.Nr. 2.4665, DIN NiCr22Fe18Mo and GH3536. Jiangyin Jiangnan Metal Co., Ltd. forges it into rings, rolled rings, discs, shafts, sleeves, flanges and tube sheets to ASTM B572, ASME SB-572 and AMS 5754.
- UNSN06002
- Werkstoff2.4665
- Trade nameHastelloy X
- Density8.22 g/cm³
- Max service1204 °C
What is UNS N06002?
UNS N06002 is a nickel-chromium-iron-molybdenum superalloy that gets its strength from solid solution rather than from precipitation hardening. Molybdenum and tungsten stiffen the nickel matrix. Chromium forms the protective oxide scale. Iron keeps the alloy cheaper and easier to hot work than a fully nickel-based grade.
Two properties account for most orders. The first is oxidation resistance to about 1204 °C, which puts the alloy into combustor cans, transition ducts, spray bars and flame holders in gas turbines. Furnace rolls made from UNS N06002 have run 8,700 hours at 1177 °C and remained serviceable. The second is resistance to stress-corrosion cracking in petrochemical service, where 300-series stainless steels crack.
UNS N06002 is easier to work than most superalloys. It forges cleanly once the whole section is soaked through at 1177 °C, cold forms well because of its ductility, and welds by SMAW, GTAW and GMAW without the reheat cracking seen in gamma-prime strengthened grades. For open-die work that means better shape control on large rings and discs, and a lower reject rate.
Where UNS N06002 is not the right choice
UNS N06002 does not age harden. If you need room-temperature yield strength above about 400 MPa, specify Inconel 718 or Waspaloy instead. For seawater, chlorides, sulphuric acid or hydrochloric acid, Hastelloy C-276 and Inconel 625 perform better. Above 900 °C the long-term creep strength of UNS N06002 is below that of Haynes 230 (UNS N06230), which is worth comparing if the service life runs to years at temperature.
UNS N06002 equivalent grades and designations
UNS N06002 appears in enquiries under several names. They all refer to the same alloy. A certificate to any one of these designations is acceptable for the others provided the chemistry and mechanical results are met.
| System | Designation | Notes |
|---|---|---|
| UNS (USA) | N06002 | Wrought product. W86002 covers weld filler. |
| Trade name | Hastelloy X | Registered trademark of Haynes International. |
| Generic | Alloy X / Nickel Alloy X / HX | Trademark-neutral names used in tenders. |
| Werkstoff (DE) | 2.4665 | German material number. |
| DIN (DE) | NiCr22Fe18Mo | Composition-based designation. |
| China (GB/T) | GH3536, formerly GH536 | Chinese superalloy grade. K536 is the cast version. |
| Other | Pyromet 680 | Carpenter Technology designation. |
| EN alternative | NiCr21Fe18Mo9 | Occasionally seen on European drawings. |
Product specifications
| Product form | ASTM | ASME | AMS |
|---|---|---|---|
| Bar, rod, forging stock | B572 | SB-572 | 5754 |
| Forgings, rings | B572 (stock) | SB-572 | 5754 |
| Plate, sheet, strip | B435 | SB-435 | 5536 |
| Seamless pipe and tube | B622 | SB-622 | n/a |
| Welded pipe | B619 | SB-619 | n/a |
| Welded tube | B626 | SB-626 | n/a |
| Fittings | B366 | SB-366 | n/a |
| Welding wire | n/a | n/a | 5798 |
UNS N06002 is covered by ASME Boiler and Pressure Vessel Code, Section VIII, Division 1 and is listed in NACE MR0175 / ISO 15156. State the edition and any code case requirement on the enquiry.
UNS N06002 chemical composition
The chemical composition of UNS N06002 is nickel as balance (nominally 47%), 20.5 to 23.0% chromium, 17.0 to 20.0% iron, 8.0 to 10.0% molybdenum, 0.2 to 1.0% tungsten, 0.5 to 2.5% cobalt and 0.05 to 0.15% carbon, with controlled residuals. Every heat is certified by spectrographic and combustion analysis.
| Element | Ni | Cr | Fe | Mo | W | Co | C |
|---|---|---|---|---|---|---|---|
| Range | Balance | 20.5-23.0 | 17.0-20.0 | 8.0-10.0 | 0.2-1.0 | 0.5-2.5 | 0.05-0.15 |
| Nominal | 47 | 22 | 18.5 | 9 | 0.6 | 1.5 | 0.10 |
| Element | Mn | Si | Al | Ti | Cu | P | S | B |
|---|---|---|---|---|---|---|---|---|
| Maximum | 1.00 | 1.00 | 0.50 | 0.15 | 0.50 | 0.040 | 0.030 | 0.010 |
Limits follow ASTM B572 and AMS 5754. Where your specification is tighter, for example a lower sulphur ceiling for hot workability or a cobalt restriction for nuclear service, state it on the enquiry.
UNS N06002 mechanical properties
In the solution-annealed condition, UNS N06002 forgings show a typical room-temperature tensile strength of 762 MPa (110,600 psi), a 0.2% offset yield strength of 379 MPa (54,900 psi) and 44% elongation in 2 inches. Strength falls with temperature while ductility is maintained.
| Temperature | Tensile strength | 0.2% yield strength | Elongation in 2 in. |
|---|---|---|---|
| 21 °C / 70 °F | 762 MPa / 110,600 psi | 379 MPa / 54,900 psi | 44% |
| 540 °C / 1000 °F | 650 MPa / 94,300 psi | 275 MPa / 39,900 psi | 45% |
| 760 °C / 1400 °F | 440 MPa / 63,800 psi | 250 MPa / 36,300 psi | 50% |
| 870 °C / 1600 °F | 255 MPa / 37,000 psi | 180 MPa / 26,100 psi | 55% |
| 980 °C / 1800 °F | 140 MPa / 20,300 psi | 90 MPa / 13,100 psi | 65% |
Values above 21 °C are typical published data for solution-annealed material and are given for design guidance. Acceptance is to the minima of the specification edition nominated on the order (ASTM B572, AMS 5754 or your own drawing). Section size, forging ratio and grain size all affect results, so tests are taken from prolongations on the actual forging. Creep and stress-rupture data are available on request.
UNS N06002 physical properties
| Property | Metric | Imperial |
|---|---|---|
| Density | 8.22 g/cm³ | 0.297 lb/in³ |
| Melting range | 1260-1355 °C | 2300-2470 °F |
| Modulus of elasticity | 205 GPa | 29.8 x 10⁶ psi |
| Thermal conductivity | 9.1 W/m·°C | 63 Btu·in/h·ft²·°F |
| Mean expansion, 20-100 °C | 13.9 µm/m·°C | 7.7 µin/in·°F |
| Specific heat | 486 J/kg·°C | 0.116 Btu/lb·°F |
| Electrical resistivity | 1.18 µΩ·m | 710 Ω·circ mil/ft |
| Crystal structure | Face-centred cubic, austenitic | n/a |
| Magnetic response | Essentially non-magnetic | n/a |
At 8.22 g/cm³ a UNS N06002 forging weighs about 5% more than the same shape in carbon steel. Confirm whether an enquiry weight is finished or as-forged.
UNS N06002 forged products and size range
Jiangyin Jiangnan Metal Co., Ltd. produces UNS N06002 open-die forgings including seamless rolled rings up to 3,000 mm outside diameter, forged discs up to 2,500 mm diameter, forged shafts up to 1,200 mm diameter and 8,000 mm length, and single pieces from 5 kg to 20,000 kg finished weight.
-
Forged rings and seamless rolled rings
Ring-rolled on mandrel for continuous circumferential grain flow.
OD 100-3,000 mm / H 1,000 mm max / wall 20 mm min -
Forged discs and blanks
Upset and drawn from cogged billet. Turbine and valve blanks.
Dia 100-2,500 mm / t 20-800 mm -
Forged shafts and round bars
Stepped, eccentric and plain shafts, spindles and forging stock.
Dia 50-1,200 mm / L 8,000 mm max -
Forged sleeves and bushings
Hollow forgings, bored and trepanned where the wall permits.
OD 100-2,000 mm / L 3,000 mm max -
Forged flanges
WN, SO, blind and special profiles to ASME B16.5, B16.47 or drawing.
Up to 2,000 mm OD -
Forged tube sheets and plates
For shell-and-tube exchangers and pressure vessels.
Up to 3,000 mm dia / t 500 mm max -
Forged blocks and valve parts
Rectangular blocks, valve bodies, seat rings and stems.
Up to 20 t single piece -
Nozzles, spindles, gear blanks
Near-net shapes with machining allowance to your drawing.
To drawing
The ranges above are typical open-die capability. Large or thin-wall geometries are checked against the drawing before quotation.
How UNS N06002 forgings are produced
The production route for a UNS N06002 forging is as follows.
-
Melting and billet supply
EAF with AOD or VOD refining, plus ESR remelt where the specification or the section size requires it. Every billet is traceable to a heat number carried through to the mill certificate.
-
Heating and soak
The billet is soaked at approximately 1177 °C (2150 °F) long enough to bring the entire section to temperature. Forging a cold core is the most common cause of centre bursts in this alloy.
-
Open-die forging or ring rolling
Cogging, upsetting and drawing on hydraulic press, or mandrel ring rolling for seamless rings. Finish temperature is controlled to keep the last reduction inside the safe hot-working window and to close the centre.
-
Solution annealing
Solution anneal at about 1177 °C (2150 °F) followed by rapid cooling. There is no ageing step, because UNS N06002 is solid-solution strengthened. Annealing below the solution temperature precipitates secondary phases and reduces both strength and ductility.
-
Rough machining
Turning, boring and facing to leave the machining allowance stated on the order, so the part arrives ready for your finish operations.
-
Testing and non-destructive examination
Chemical analysis, tensile and hardness testing on prolongations, grain size, and ultrasonic examination to EN 10228-3, SEP 1921 or ASTM A388. PT, MT, intergranular corrosion testing and impact testing on request.
-
Certification and despatch
EN 10204 3.1 certificate as standard. EN 10204 3.2 with TUV, SGS, BV, Lloyd's Register or DNV countersignature on request. Marking, preservation and packing to your shipping specification.
Testing, inspection and certification
UNS N06002 forgings from Jiangyin Jiangnan Metal are ultrasonically tested to EN 10228-3, SEP 1921 or ASTM A388 and released with an EN 10204 3.1 mill certificate as standard, or EN 10204 3.2 countersigned by a third-party inspection body on request.
| Test | Standard | Scope |
|---|---|---|
| Chemical analysis | ASTM E1473 / E1019 | Every heat, standard |
| Tensile test | ASTM E8 / ISO 6892-1 | Prolongation from the forging, standard |
| Hardness | ASTM E10 / E18 | Standard |
| Grain size | ASTM E112 | Standard |
| Ultrasonic testing | EN 10228-3 / SEP 1921 / ASTM A388 | Standard, acceptance class per order |
| Penetrant or magnetic particle | ASTM E165 / E1444 | On request |
| Impact test | ASTM E23 / ISO 148-1 | On request |
| Intergranular corrosion | ASTM G28 method A | On request |
| Material certificate | EN 10204 3.1 / 3.2 | 3.1 standard, 3.2 on request |
Third-party witnessed inspection is scheduled into the production plan at order stage. If your project has an inspection and test plan, send it with the enquiry so hold and witness points are priced correctly.
Applications for UNS N06002 forgings
UNS N06002 forgings are used where high temperature, aggressive atmosphere and thermal cycling occur together. These are the sectors they ship into.
| Industry | Typical components | Reason for UNS N06002 |
|---|---|---|
| Gas turbines and aero engines | Combustor can rings, transition duct rings, flame-holder rings, afterburner and tailpipe rings, seal rings | Oxidation resistance and strength through the hot gas path, plus good weldability for fabricated assemblies |
| Industrial furnaces and heat treatment | Furnace rolls, retort rings, muffle components, fixture and tray hardware, radiant tube rings | Withstands oxidising, reducing and neutral atmospheres. Carburisation and nitriding resistance |
| Petrochemical and refining | Reformer and cracker flanges, tube sheets, nozzles, valve bodies and seat rings | Resistance to stress-corrosion cracking at temperature |
| Power generation | Turbine casing rings, spindles, gearbox and rotor components, generator hardware | Thermal-fatigue resistance under start-stop cycling |
| Chemical process plant | Pressure-vessel flanges, heat-exchanger tube sheets, agitator and pump shafts, column internals | Stable in mixed high-temperature process environments |
| Nuclear and research | Gas-cooled reactor internals, high-temperature test rigs | Long-established high-temperature data and code coverage |
Frequently asked questions about UNS N06002
Is UNS N06002 the same as Hastelloy X?
Yes. UNS N06002 is the UNS designation for the alloy sold under the Haynes International trade name HASTELLOY X. The same alloy is also designated W.Nr. 2.4665, DIN NiCr22Fe18Mo, Alloy X, Pyromet 680 and, in China, GH3536. UNS N06002 is the trademark-neutral designation, which is why tenders and drawings usually call it out that way.
Can UNS N06002 be age hardened?
No. UNS N06002 is solid-solution strengthened, not precipitation hardening, so there is no ageing treatment for it. The correct heat treatment is a solution anneal at approximately 1177 °C (2150 °F) followed by rapid cooling. Annealing below the solution temperature can precipitate secondary phases and reduce strength and ductility, so partial or stress-relief anneals should be avoided unless the specification calls for one.
Material offered as "solution treated and aged" UNS N06002 has not been heat treated correctly for this grade.
What is the maximum service temperature of UNS N06002?
UNS N06002 stays oxidation resistant in air to about 1204 °C (2200 °F), and it retains useful ductility after 16,000 hours at 650 °C, 760 °C and 870 °C. That oxidation figure is not a design allowable. For a loaded component the limit is set by creep and stress rupture and is usually much lower. Take allowables from ASME Section VIII, Division 1 or from creep data matched to the required service life.
What is the difference between UNS N06002 and Inconel 625?
They solve different problems. UNS N06002 (Hastelloy X) is a high-temperature alloy with about 18 to 20% iron and 9% molybdenum, used for oxidation resistance and strength in hot gas and furnace service. Inconel 625 (UNS N06625) is a wet-corrosion alloy with much lower iron, about 9% molybdenum plus 3.15 to 4.15% niobium, used for seawater, chloride and acid resistance.
In practice: for hot gas paths and furnace internals use UNS N06002, and for seawater, chlorides and acids use Inconel 625. Where both conditions apply, Inconel 617 or Haynes 230 is usually the better answer.
What sizes of UNS N06002 forged rings can you make?
Seamless rolled rings and forged rings from about 100 mm to 3,000 mm outside diameter, up to 1,000 mm height, with finished single-piece weights from 5 kg to about 20,000 kg. Forged discs run to about 2,500 mm diameter and forged shafts to about 1,200 mm diameter by 8,000 mm length. Capability for a specific geometry is confirmed against the drawing before quotation.
Which standards do you certify UNS N06002 forgings to?
ASTM B572, ASME SB-572 and AMS 5754 for bar, forging stock and forgings. The alloy is covered by ASME Boiler and Pressure Vessel Code Section VIII, Division 1 and is listed in NACE MR0175 / ISO 15156. We also work to customer drawings and to European and Japanese equivalents where the enquiry calls for them.
What certificates come with the forgings?
EN 10204 3.1 as standard, covering heat number, chemical analysis, mechanical test results, heat-treatment record, ultrasonic report and dimensional report. EN 10204 3.2 countersigned by TUV, SGS, BV, Lloyd's Register or DNV is available on request and should be stated at enquiry stage so the inspection is planned rather than added later.
What is the lead time and minimum order quantity?
Typical lead time is 25 to 45 days from order confirmation, covering billet release, forging, solution annealing, rough machining, testing and certification. Simple rings from stock billet sit at the short end. Large or heavily machined parts and third-party witnessed inspection sit at the long end.
There is no fixed minimum quantity. Single prototype pieces are quoted as well as production batches, although the unit price on a one-off reflects the billet and set-up cost.
Who supplies UNS N06002 forged rings and discs in China?
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, producing UNS N06002 (Hastelloy X) forged rings, seamless rolled rings, discs, shafts, sleeves, bushings, flanges and tube sheets to ASTM B572 and AMS 5754. Enquiries go to sales@steelforgepieces.com or +86 189 2135 9659.
Send a drawing, get a price in 24 hours
Send the drawing or the raw dimensions. We return a firm price, a delivery date and the testing scope. If you are still selecting a grade, send the service temperature and atmosphere instead and we will confirm whether UNS N06002 is suitable.
Include if you have it: finished dimensions or drawing, quantity, specification and edition (ASTM B572, AMS 5754 or your own), required heat-treatment condition, machining allowance, UT acceptance class, certificate type (EN 10204 3.1 or 3.2), destination port.
- CompanyJiangyin Jiangnan Metal Co., Ltd., open-die forging factory
- AddressNo.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China
- Phone+86 189 2135 9659 (WhatsApp / WeChat)
- Emailsales@steelforgepieces.com
- Websitewww.steelforgepieces.com