Alloy HX Forgings UNS N06002 · W.Nr. 2.4665 · NiCr22Fe18Mo · also sold as Hastelloy® X and Inconel® HX
Updated August 2026
- Alloy family
- Nickel-chromium-iron-molybdenum, solid-solution strengthened
- UNS / W.Nr.
- N06002 / 2.4665
- Common names
- Alloy HX · Alloy X · Hastelloy® X · Inconel® HX · NiCr22Fe18Mo
- Nominal chemistry
- Ni 47 · Cr 22 · Fe 18 · Mo 9 · Co 1.5 · W 0.6 (wt %)
- Bar / billet spec
- ASTM B572 · ASME SB-572 · AMS 5754
- Forging spec
- ASTM B564
- Supplied condition
- Solution annealed 1177 °C (2150 °F), rapid cooled. Not aged.
- Room-temp minima
- UTS 655 MPa (95 ksi) · YS 240 MPa (35 ksi) · Elong. 35 %
- Max oxidation service
- approx. 1200 °C (2200 °F)
- Forms produced here
- Rolled rings · discs · shafts · flanges · sleeves · bars · tube sheets
- Certification
- EN 10204 3.1 standard, 3.2 third-party on request
- Produced by
- Jiangyin Jiangnan Metal Co., Ltd., Jiangyin, Jiangsu, China
+86-189-2135-9659 · sales@steelforgepieces.com
Alloy HX (UNS N06002) is a nickel-chromium-iron-molybdenum superalloy for high-temperature service. It holds oxidation resistance to about 1200 °C and forges more easily than most superalloys. Strength at temperature comes from molybdenum, cobalt and tungsten held in solid solution, not from precipitation hardening as in Inconel 718.
Jiangyin Jiangnan Metal Co., Ltd. forges Alloy HX to drawing at its open-die plant in Jiangyin, Jiangsu Province, China. Products include seamless rolled rings, discs, shafts, flanges, sleeves and tube sheets, supplied solution annealed with EN 10204 3.1 or 3.2 certificates.
Alloy design
Each element in Alloy HX does a specific job. Nickel resists carburisation, nitridation and chlorination. Chromium at 20.5 to 23 % forms the oxide layer that carries the alloy to 1200 °C. Molybdenum at 8 to 10 %, together with cobalt and tungsten, stiffens the matrix and provides creep strength. Iron at 17 to 20 % is a deliberate addition that lowers cost with little loss of performance.
The alloy has been specified for gas turbine combustor hardware since the 1950s and is still in production for the same duty.
Alloy HX is not precipitation hardenable. Do not specify a solution plus ageing cycle by default. The material is supplied solution heat treated at 1177 °C (2150 °F) and rapidly cooled. Annealing below the solution temperature precipitates secondary carbides and mu phase, which lowers ductility and toughness. Long exposure in the 650 to 870 °C band during service has the same effect, so design life should allow for it.
Designations and standards
| System | Designation or standard | Applies to |
|---|---|---|
| UNS | N06002 | All forms |
| Werkstoff | 2.4665 | All forms |
| DIN | NiCr22Fe18Mo | All forms |
| ASTM / ASME | B572 / SB-572 | Rod, bar, billet. Primary spec for forging stock |
| ASTM | B564 | Nickel alloy forgings |
| ASTM / ASME | B435 / SB-435 | Plate, sheet, strip |
| ASTM / ASME | B619, B622, B626 | Welded pipe, seamless pipe and tube, welded tube |
| ASTM / ASME | B366 / SB-366 | Fittings |
| AMS | 5754 | Bar, forgings, rings, billet. Aerospace |
| AMS | 5536 | Sheet, strip, plate. Aerospace |
| ASME BPVC | Section VIII Div. 1 | Pressure-retaining components |
| Welding | AWS A5.14 ERNiCrMo-2 / A5.11 ENiCrMo-2 | Matching filler metal |
Chemical composition
Limits follow ASTM B572 for UNS N06002. Cobalt and tungsten are often left out of short datasheets, and those are the two elements that separate Alloy HX from a plain Ni-Cr-Fe-Mo alloy. Every heat is verified by optical emission spectrometry, with carbon and sulphur by combustion analysis.
| Element | Min | Max | Nominal | Function |
|---|---|---|---|---|
| Nickel (Ni) | - | Balance | 47 | Matrix. Carburisation and chlorination resistance |
| Chromium (Cr) | 20.5 | 23.0 | 22 | Protective oxide, oxidation resistance to 1200 °C |
| Iron (Fe) | 17.0 | 20.0 | 18 | Matrix stabiliser. Lowers alloy cost |
| Molybdenum (Mo) | 8.00 | 10.00 | 9.0 | Main solid-solution strengthener |
| Cobalt (Co) | 0.50 | 2.50 | 1.5 | Creep strength at temperature |
| Tungsten (W) | 0.20 | 1.00 | 0.6 | Creep and oxidation resistance |
| Carbon (C) | 0.05 | 0.15 | 0.10 | Carbide strengthening, grain boundary pinning |
| Manganese (Mn) | - | 1.00 | - | Deoxidiser |
| Silicon (Si) | - | 1.00 | - | Deoxidiser |
| Aluminium (Al) | - | 0.50 | - | Residual |
| Titanium (Ti) | - | 0.15 | - | Residual |
| Boron (B) | - | 0.010 | - | Grain boundary strengthening |
| Phosphorus (P) | - | 0.040 | - | Impurity, controlled |
| Sulphur (S) | - | 0.030 | - | Impurity, controlled for hot workability |
Mechanical properties
The figures below are the room temperature minima required by ASTM B572 in the solution annealed condition, with typical measured values alongside. Forged properties normally run well above the specification minima, which are set conservatively.
| Property | Metric min | Imperial min | Typical |
|---|---|---|---|
| Ultimate tensile strength | 655 MPa | 95 ksi | 730 to 790 MPa |
| Yield strength, 0.2 % offset | 240 MPa | 35 ksi | 310 to 380 MPa |
| Elongation in 4D | 35 % | 35 % | 40 to 50 % |
| Reduction of area | Report | Report | 45 to 60 % |
| Hardness | Report | Report | 100 HRB max |
| Grain size, ASTM E112 | Report | Report | ASTM 3 to 7 |
Elevated temperature tensile data and stress rupture testing to ASTM E139 can be run on production coupons. State the temperatures and durations on the enquiry so the coupon is planned into the forging before it is cut.
Physical properties
| Property | Metric | Imperial |
|---|---|---|
| Density | 8.22 g/cm³ | 0.297 lb/in³ |
| Melting range | 1260 to 1355 °C | 2300 to 2470 °F |
| Modulus of elasticity | 205 GPa | 29.8 × 10&sup6; psi |
| Mean CTE, 25 to 100 °C | 13.9 µm/m·°C | 7.7 µin/in·°F |
| Thermal conductivity | 9.1 W/m·K | 63 Btu·in/h·ft²·°F |
| Specific heat | 486 J/kg·K | 0.116 Btu/lb·°F |
| Electrical resistivity | 1.18 µΩ·m | 718 Ω·circ mil/ft |
| Magnetic permeability | Essentially non-magnetic, about 1.002 at 200 Oe | |
Forging and heat treatment
Alloy HX forges more readily than most nickel superalloys. The working window is still narrower than for steel. Shop practice is set out below.
| Operation | Temperature | Notes |
|---|---|---|
| Soak before forging | 1177 °C / 2150 °F | Hold long enough for the full section to reach temperature. A cold core cracks on the first blow. |
| Forging start | 1170 °C max | Take heavy reduction in the first heats while ductility is highest. |
| Finishing temperature | above 950 °C | Finishing colder risks cracking and leaves a mixed grain structure. |
| Reheats | 1177 °C | Reheat rather than force a cold finish. Several reheats are normal on large rings. |
| Solution anneal | 1177 °C / 2150 °F | Followed by rapid cooling, water or forced air by section size. This is the supply condition. |
| Ageing | Not applicable | Solid-solution alloy. No ageing step unless a customer specification calls for one. |
| Sub-solution anneal | Avoid | Annealing below solution temperature precipitates carbides and mu phase and cuts ductility. |
| Cold working | Room temperature | Cold forms readily. Re-solution anneal afterwards. |
| Welding | - | GTAW, GMAW, SMAW and resistance welding with ERNiCrMo-2 or ENiCrMo-2. Low heat input, low interpass temperature. Submerged arc is not recommended. |
Melting route
Forging billet is supplied either as vacuum induction melted then electroslag remelted (VIM plus ESR), or by an electric arc route with AOD or VOD refining followed by ESR. The remelt step controls sulphur, dissolved gas and inclusion cleanliness, which governs hot workability and ultrasonic acceptance on heavy sections. Aerospace specifications such as AMS 5754 may restrict the acceptable route, so the melting practice is confirmed on the quotation.
Alloy HX forged products
All items below are open-die forged or ring rolled to drawing. There is no fixed catalogue of sizes. Non-standard sections, single replacement parts and obsolete OEM geometries are normal work.
- Alloy HX forged ringsRolled and open-die
- Alloy HX seamless rolled ringsRadial-axial rolled
- Alloy HX forged discs and blanksUpset and pierced
- Alloy HX forged shafts and spindlesStepped and plain
- Alloy HX forged flangesWN, blind, special
- Alloy HX forged round barsRough turned or black
- Alloy HX sleeves and bushingsBored hollows
- Alloy HX tube sheetsDrilled to drawing
- Alloy HX valve bodies and stemsNear-net forged
- Alloy HX nozzles and manifoldsHot formed
Forging capability
| Form | Outside diameter | Height / length | Single-piece weight |
|---|---|---|---|
| Seamless rolled rings | 200 to 3000 mm | up to 800 mm | 10 to 5000 kg |
| Forged discs and blanks | 100 to 2000 mm | 20 to 600 mm thk | 5 to 4000 kg |
| Shafts and bars | 60 to 800 mm | up to 6000 mm | 10 to 6000 kg |
| Sleeves and hollow bars | 100 to 1500 mm | up to 3000 mm | 10 to 4000 kg |
| Flanges and tube sheets | 100 to 2500 mm | to drawing | 5 to 4000 kg |
Machining allowance is agreed on the forging drawing before production. Finish machining, boring and drilling are carried out in house so the part arrives ready to install.
Testing and certification
| Test | Standard | Included |
|---|---|---|
| Chemical analysis | OES and LECO combustion | Standard, every heat |
| Room temp tensile | ASTM E8 / ISO 6892-1 | Standard |
| Hardness | ASTM E18 | Standard |
| Grain size | ASTM E112 | Standard |
| Ultrasonic testing | EN 10228-3 / SEP 1921 / ASTM A388 | Standard, class on request |
| Liquid penetrant | ASTM E165 / EN 10228-2 | On request |
| Elevated temp tensile | ASTM E21 | On request |
| Stress rupture and creep | ASTM E139 | On request |
| Intergranular corrosion | ASTM G28 | On request |
| Mill test certificate | EN 10204 3.1 | Standard |
| Third-party witnessed | EN 10204 3.2 | On request. TUV, SGS, BV, LR |
Each forging carries a heat number, stamped or vibro-etched on the part, cross-referenced to the melt certificate, forging record, heat treatment chart and test report. Documentation packs are issued as PDF before shipment so incoming inspection can be planned in advance.
Applications
Gas turbines and aero engines
The original application and still the largest. Combustion zone hardware including transition ducts, combustor cans, spray bars and flame holders, plus afterburners, tailpipes and cabin heaters. Forged rings and discs feed casing and liner assemblies.
Industrial furnaces and heat treatment
Furnace rolls, muffles, retorts, baffles, trays, radiant tubes and support structures. The deciding property is resistance to oxidising, reducing and neutral atmospheres alike. Furnace rolls in this alloy have been reported still serviceable after 8,700 hours at 1177 °C.
Petrochemical and chemical processing
Reformer and cracking furnace internals, flare tips, incinerator components, catalyst grid supports. Alloy HX also resists chloride stress corrosion cracking, which is why it appears in petrochemical service outside the turbine market.
Power generation
Land-based gas turbine hot sections, waste-to-energy and biomass boiler internals, high temperature valve and pressure part forgings under ASME Section VIII Div. 1.
Nuclear and research
High temperature gas-cooled reactor components, hot cell and test loop hardware where prolonged exposure above 800 °C is expected.
Alloy HX compared with other grades
Alloy HX is normally weighed against these three grades. The table gives the short version of the trade-off.
| Alloy HX N06002 |
Inconel 617 N06617 |
Inconel 625 N06625 |
Incoloy 800H N08810 |
|
|---|---|---|---|---|
| Strengthening | Solid solution | Solid solution | Solid solution + Nb | Solid solution |
| Ni, nominal % | 47 | 52 | 60 | 32 |
| Cr, % | 20.5 to 23 | 20 to 24 | 20 to 23 | 19 to 23 |
| Mo, % | 8 to 10 | 8 to 10 | 8 to 10 | - |
| Co, % | 0.5 to 2.5 | 10 to 15 | 1.0 max | - |
| Oxidation limit | 1200 °C | 1100 °C | 980 °C | 1100 °C |
| Creep above 900 °C | Very good | Best of the four | Moderate | Good |
| Aqueous corrosion | Moderate | Moderate | Best of the four | Moderate |
| Forgeability | Very good | Good | Good | Very good |
| Relative cost | Medium | High, cobalt | Medium-high | Low |
| Specify when | Sustained heat in oxidising or reducing gas, and the part has to be forged | Creep governs above 950 °C and budget allows | Chloride or acid corrosion governs, not heat | Heat matters but cost governs |
All four grades are forged here. Related pages: Inconel 617 forgings, Inconel 625 forgings, Incoloy 800H forgings, Hastelloy X forgings.
How to order
- Send the drawing or dimensionsA drawing is best, but a sketch or a set of finished dimensions works. State the quantity, the governing specification, and whether you want machining allowance or a finish-machined part.
- Receive the quotationUsually back within one working day. Covers forged weight, melting route, heat treatment, test scope and lead time.
- Approve the forging drawingA forging drawing showing the as-forged envelope, machining allowance and test coupon location is issued for sign-off. Nothing goes to the furnace before approval.
- Forging and heat treatmentBillet soaked at 1177 °C, open-die forged or ring rolled, then solution annealed at 1177 °C and rapidly cooled.
- Test, certify, shipChemistry, tensile, hardness, grain size and UT completed. EN 10204 3.1 or 3.2 certificate issued. Packed for sea or air freight from Shanghai.
Frequently asked questions
Is Alloy HX the same as Hastelloy X and Inconel HX?
Yes. Alloy HX, Hastelloy X, Inconel HX and Alloy X all cover the same chemistry: UNS N06002, W.Nr. 2.4665, NiCr22Fe18Mo. The names differ because they come from different producers.
HASTELLOY® is a registered trademark of Haynes International, Inc. INCONEL® and INCOLOY® are registered trademarks of Special Metals Corporation. Jiangyin Jiangnan Metal Co., Ltd. is not affiliated with either company and uses these names only to identify the chemistry supplied.
Can Alloy HX be age hardened?
No. Alloy HX is solid-solution strengthened, not precipitation hardenable. Strength at temperature comes from molybdenum, cobalt and tungsten dissolved in the nickel-chromium matrix. There is no gamma prime ageing step.
Forged and wrought product is supplied solution heat treated at 1177 °C (2150 °F) and rapidly cooled. Annealing below the solution temperature precipitates secondary carbides and mu phase, which lowers ductility. Specify an ageing cycle only if a customer or OEM specification calls for one.
Which standards cover Alloy HX forgings?
Bar, billet and rod fall under ASTM B572 and ASME SB-572, with AMS 5754 as the aerospace equivalent. Nickel alloy forgings are covered by ASTM B564. Plate, sheet and strip come under ASTM B435 and AMS 5536. Pipe and tube come under ASTM B619, B622 and B626. Fittings come under ASTM B366.
Jiangyin Jiangnan Metal Co., Ltd. supplies Alloy HX forgings to ASTM B572 and ASTM B564 with EN 10204 3.1 or 3.2 certification.
What is the maximum service temperature of Alloy HX?
Alloy HX holds useful oxidation resistance to about 1200 °C (2200 °F) in oxidising, reducing and neutral atmospheres. Continuous load-bearing service is normally limited to 900 to 1100 °C depending on stress and design life, because creep rather than oxidation becomes the governing mechanism above that range.
For reference, furnace rolls in this alloy have been reported still serviceable after 8,700 hours at 1177 °C.
What forged shapes can be supplied in Alloy HX?
Seamless rolled rings, forged rings, discs, blanks, shafts, spindles, round bars, flanges, sleeves, bushings, hollow bars, tube sheets, valve bodies and nozzles.
Parts are open-die forged to drawing rather than cut from catalogue stock, so non-standard sections, single replacement pieces and obsolete OEM geometries are normal work here.
What testing and certification comes with the forgings?
Every heat is supplied with chemical analysis, room temperature tensile properties, hardness and grain size on an EN 10204 3.1 certificate. Ultrasonic testing to EN 10228-3, SEP 1921 or ASTM A388 is standard.
EN 10204 3.2 certificates witnessed by TUV, SGS, BV or Lloyd's Register are available on request, along with liquid penetrant inspection, elevated temperature tensile testing to ASTM E21 and stress rupture testing to ASTM E139.
Should I use Alloy HX or Inconel 625?
Use Alloy HX when the governing condition is sustained high temperature above about 900 °C in oxidising, reducing or carburising gas. Typical cases are gas turbine combustors, furnace internals and flare hardware.
Use Inconel 625 when the governing condition is aqueous or chloride corrosion at low to moderate temperature, such as seawater, acid service and flue gas desulphurisation. Alloy HX is stronger on creep and oxidation above 900 °C. Inconel 625 is stronger at room temperature and better on pitting resistance.
What is the minimum order quantity and lead time?
There is no fixed piece count minimum. Single forgings and prototypes are accepted, and the practical floor is set by billet size rather than by quantity.
Lead time is normally four to eight weeks from drawing approval, driven by forged weight, billet availability and test scope. Email sales@steelforgepieces.com or call +86-189-2135-9659 for a firm date.
Where is the factory located?
Jiangyin Jiangnan Metal Co., Ltd. is at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China.
Jiangyin is on the Yangtze River between Shanghai and Nanjing, about 150 km from Shanghai Port, which is the usual export route. Sales contact: +86-189-2135-9659 or sales@steelforgepieces.com.
How is Alloy HX melted before forging?
Billet is normally vacuum induction melted then electroslag remelted (VIM plus ESR), or produced by an electric arc route with AOD or VOD refining followed by ESR.
The remelt step controls sulphur, dissolved gas and inclusion cleanliness, which governs hot workability and ultrasonic acceptance on heavy sections. Aerospace specifications such as AMS 5754 may restrict which routes are acceptable, so the melting practice is confirmed on the quotation.
About the manufacturer
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China. The plant produces forged rings, seamless rolled rings, discs, shafts, flanges, sleeves, bushings, tube sheets and bars in nickel superalloys, stainless steel, tool steel, alloy steel and carbon steel, working to customer drawings rather than to a fixed catalogue.
Alloy HX (UNS N06002) sits in the nickel superalloy programme alongside Inconel 600, 601, 617, 625, 718 and X-750, Incoloy 800H, 800HT, 825 and 925, and the Hastelloy B and C families. Forgings are ultrasonically tested to EN 10228-3, SEP 1921 or ASTM A388 and certified to EN 10204 3.1, with 3.2 third-party certification available. Jiangyin is on the Yangtze River between Shanghai and Nanjing, about 150 km from Shanghai Port.
Request a quotation
Send a drawing, a sketch or the finished dimensions and quantity. Quotations usually go out within one working day and cover forged weight, heat treatment, test scope and lead time.
Jiangyin Jiangnan Metal Co., Ltd.No.1 Chengxiqiao Road, Zhouzhuang Town
Jiangyin City, Jiangsu Province, China 214423
Tel / WhatsApp / WeChat: +86-189-2135-9659
Email: sales@steelforgepieces.com Email your drawing