UNS N06007 forgings
Alloy G · Hastelloy® G · W.Nr. 2.4618 · NiCr22Fe20Mo6Cu2Nb
UNS N06007 is a nickel-chromium-iron-molybdenum-copper alloy with a niobium addition, used for equipment in hot phosphoric acid, sulfuric acid and mixed acid service. It is a solid-solution grade. There is no aging response, so forgings are supplied solution annealed and quenched.
We forge N06007 to order: seamless rolled rings, flanges, shafts, discs, sleeves, bushings, tube sheets, hollow bars and round bars. Parts ship solution annealed, machined to your drawing, ultrasonically tested, with EN 10204 3.1 or 3.2 certification.
What is UNS N06007?
UNS N06007 is the UNS number for the alloy sold as Hastelloy® G, also called Alloy G. Nominal composition is about 44 % nickel, 22 % chromium, 20 % iron and 6.5 % molybdenum, with 2 % copper and 2 % niobium plus tantalum.
Chromium carries the alloy in oxidizing acids. Molybdenum and copper carry it in reducing acids, which is why it holds up in sulfuric and phosphoric duty where a straight chromium grade would not. The niobium ties up carbon and keeps chromium carbides from forming at grain boundaries during welding, so the heat-affected zone stays resistant to intergranular attack.
The structure is single-phase austenitic and stays that way. There is no aging response. Forgings are supplied solution annealed and machined from that condition.
Specification note. Most new plant now specifies Alloy G-3 (UNS N06985) or Alloy G-30 (UNS N06030) in place of Alloy G. N06007 is still bought for replacement parts in older plant, and where a drawing or an old material spec names it. If you are building new, ask us to price N06007 and N06985 together and compare the lead time.
Chemical composition
Limits below are the ASTM requirements for N06007. Each heat ships with its own certificate showing the ladle analysis against these limits.
| Element | Min % | Max % | Role in the alloy |
|---|---|---|---|
| Nickel (Ni) | Balance, about 44 | Austenitic matrix, resistance to chloride stress corrosion cracking | |
| Chromium (Cr) | 21.0 | 23.5 | Oxidizing media, nitric acid |
| Iron (Fe) | 18.0 | 21.0 | Cost balance, matrix stability |
| Molybdenum (Mo) | 5.5 | 7.5 | Reducing acids, pitting resistance |
| Copper (Cu) | 1.50 | 2.50 | Sulfuric and phosphoric acid |
| Niobium + tantalum (Nb+Ta) | 1.75 | 2.50 | Carbide stabilizer, protects the weld HAZ |
| Manganese (Mn) | 1.00 | 2.00 | Deoxidizer, sulfur control |
| Tungsten (W) | - | 1.00 | Residual |
| Cobalt (Co) | - | 2.50 | Residual |
| Silicon (Si) | - | 1.00 | Deoxidizer |
| Carbon (C) | - | 0.05 | Held low to limit carbide precipitation |
| Phosphorus (P) | - | 0.04 | Impurity |
| Sulfur (S) | - | 0.03 | Impurity, controlled for hot workability |
Forging stock is melted in an electric arc furnace, refined by AOD or VOD, then electroslag remelted. ESR is what gives heavy sections their low inclusion count and through-thickness uniformity.
Mechanical and physical properties
Figures below are room-temperature minimums for solution annealed material. Results on a forged section normally sit well above them. We report tested values on the certificate, not nominal ones.
| Property | Metric | Imperial |
|---|---|---|
| Tensile strength, min. | 621 MPa | 90 ksi |
| Yield strength 0.2 % offset, min. | 241 MPa | 35 ksi |
| Elongation in 4D, min. | 45 % | 45 % |
| Hardness, typical annealed | 95 HRB max | 95 HRB max |
| Property | Value |
|---|---|
| Density | 8.3 g/cm³ (0.300 lb/in³) |
| Melting range | 1260-1345 °C (2300-2450 °F) |
| Magnetic response | Non-magnetic in the annealed condition |
| Structure | Single-phase austenitic, no aging response |
Elevated-temperature allowables, impact values or corrosion test data for a specific medium can be supplied on request. Tell us the design code and the service condition.
Standards and equivalent designations
| System | Designation | Covers |
|---|---|---|
| UNS | N06007 | Unified Numbering System |
| Trade name | Alloy G, Hastelloy® G | Common commercial names |
| Werkstoff-Nr. | 2.4618 | German material number |
| DIN | NiCr22Fe20Mo6Cu2Nb | Chemical symbol designation |
| ASTM / ASME B462 | SB-462 | Forged or rolled flanges, fittings, valves and parts |
| ASTM / ASME B564 | SB-564 | Nickel alloy forgings |
| ASTM / ASME B581 | SB-581 | Rod and bar |
| ASTM / ASME B582 | SB-582 | Plate, sheet and strip |
| ASTM / ASME B622 | SB-622 | Seamless pipe and tube |
| ASTM / ASME B619 | SB-619 | Welded pipe |
| ASTM / ASME B626 | SB-626 | Welded tube |
| ASTM B366 | - | Factory-made wrought fittings |
Forgings are usually ordered to ASTM B462 or B564, bar to B581. If your specification is a client or end-user document, send it with the inquiry and we will confirm compliance before we price the job.
Forging and heat treatment
Alloy G forges well inside its window and badly outside it. It work hardens fast, the hot working range is narrower than carbon steel, and finishing cold gives you cracks and coarse grain. How we run it:
Heating
Charge into a furnace already at heat and soak through to a uniform temperature. Keep sulfur out of the atmosphere. Nickel picks it up and embrittles.
Forging window
Start around 1150 °C. Reheat before the piece drops under 930 °C rather than squeezing in the last few blows.
Reduction
Heavy reduction worked through the whole section, not just the skin. Breaking down the cast structure is the reason to forge the part instead of cutting it from bar.
Solution annealing
1150 to 1180 °C, soaked to section thickness, then water quenched or fast air cooled to hold carbides in solution.
No aging
N06007 does not precipitation harden. An aging cycle adds cost and can only hurt corrosion resistance. Solution anneal is the final thermal condition.
Descaling and machining
Pickle or grind the scale off before machining. Rigid setup, positive rake, sharp tools, plenty of coolant. Take a real cut; a light rubbing pass work hardens the surface and the next pass has to fight it.
Heat treatment note. Some datasheets list solution treatment plus aging for N06007. That is wrong for this grade. Alloy G is solid solution and does not age harden. If a drawing calls for aging, query it before you cut metal.
Forged products we supply in UNS N06007
We are an open-die shop. Everything below is made to your drawing or dimension list. Nothing is stock.
| Forged form | Typical size range | Usual delivery condition |
|---|---|---|
| Seamless rolled rings | OD 100-3000 mm, wall 20-400 mm, height 20-800 mm | Solution annealed, rough machined |
| Forged flanges | DN15-DN1500, ASME B16.5 / B16.47 / EN 1092-1 or to drawing | Finish machined, faced |
| Shafts, spindles, eccentric shafts | Dia. 60-800 mm, length up to 6000 mm | Rough or finish machined |
| Discs, disks and blanks | Dia. 100-2500 mm, thickness 20-600 mm | Solution annealed, rough machined |
| Sleeves, bushings, hollow bars | OD 80-1200 mm, bored to drawing | Rough machined, bored |
| Tube sheets and forged plates | Dia. up to 2500 mm | Solution annealed, faced |
| Round bars and blocks | Dia. 30-800 mm | Peeled or turned |
| Valve bodies, seat rings, stems, nozzles | To drawing | Rough or finish machined |
Single piece weight and maximum envelope depend on the geometry of the part. Send the drawing and we will confirm feasibility, machining allowance and weight before quoting.
Where UNS N06007 forgings are used
Alloy G was developed for wet corrosive duty where the process swings between oxidizing and reducing, or carries halides and metal contaminants. What we ship it for:
- Phosphoric acid plants. Agitator shafts, pump parts, heat exchanger tube sheets and flanges in wet process phosphoric acid.
- Sulfuric and mixed acid service. Pump casings, valve bodies, seat rings and stems.
- Flue gas desulfurization. Rings, flanges and nozzles in scrubber and absorber duty.
- Pickling and steel finishing lines. Rolls, sleeves, bushings and shafts.
- Pulp and paper. Bleach plant equipment exposed to chlorides and chlorine dioxide.
- Pressure vessels and heat exchangers. Forged shell flanges, tube sheets, nozzles and covers.
- Chemical process equipment. Columns, towers, crystallizers, reactors and process modules.
- Oil, gas and offshore. Wellhead components and subsea parts in sour and chloride-bearing fluids.
If the service is unusual, tell us the acid, the concentration, the temperature and any contaminants. We would rather point you at a different grade than sell you the wrong forging.
Testing, inspection and certification
Chemistry
Ladle analysis per heat. Product analysis and positive material identification on the finished forging when the order calls for it.
Mechanical testing
Tensile and hardness as standard. Impact, hot tensile and grain size on request. Test coupons are heat treated with the parts.
Ultrasonic testing
UT to EN 10228-3, SEP 1921 or ASTM A388, to the acceptance class stated on your order.
Surface NDT
Liquid penetrant to ASTM E165. Magnetic particle does not apply, since the alloy is non-magnetic.
Corrosion testing
Intergranular corrosion testing to ASTM G28 method A or B when specified.
Certification
EN 10204 3.1 as standard. EN 10204 3.2 with third party witness: SGS, BV, TUV, Lloyd's or your own inspector.
Traceability runs from the ingot heat number through forging, heat treatment, NDT and machining. The number is stamped or etched on the part and recorded in the certificate package.
How to get a quotation
Send a drawing or a PDF sketch with the material called out and we can price it. No drawing yet? These eight lines are enough:
- Part name, and drawing if you have one
- Forged shape: ring, flange, shaft, disc, sleeve, bar
- Rough or finished dimensions, OD x ID x height, or diameter x length
- Quantity, and unit weight if you know it
- Specification: ASTM B462, B564, B581, or your own standard
- Delivery condition: as forged, rough machined, finish machined
- NDT class, PMI and certificate level required
- Delivery date and destination port
Frequently asked questions
Is UNS N06007 the same as Hastelloy G?
Yes. N06007 is the UNS number for the alloy sold commercially as Hastelloy® G, also called Alloy G, and known in Germany by the material number 2.4618. Hastelloy® is a registered trademark of Haynes International, Inc. Jiangyin Jiangnan Metal is an independent forging shop with no affiliation to Haynes International. The trade name appears here so buyers can cross reference the grade.
What is the chemical composition of UNS N06007?
Nickel balance, about 44 %. Chromium 21.0 to 23.5 %, iron 18.0 to 21.0 %, molybdenum 5.5 to 7.5 %, copper 1.50 to 2.50 %, niobium plus tantalum 1.75 to 2.50 %, manganese 1.00 to 2.00 %. Maximums: tungsten 1.00 %, cobalt 2.50 %, silicon 1.00 %, carbon 0.05 %, phosphorus 0.04 %, sulfur 0.03 %.
What are the minimum mechanical properties of N06007 forgings?
Solution annealed, at room temperature: tensile strength 621 MPa (90 ksi) minimum, 0.2 % offset yield 241 MPa (35 ksi) minimum, elongation 45 % minimum. Annealed hardness is normally no higher than 95 HRB.
Which standards cover UNS N06007 forgings?
Forgings go to ASTM B462, which covers forged or rolled flanges, fittings, valves and parts, or to ASTM B564 for nickel alloy forgings. Rod and bar fall under B581, plate and sheet under B582, seamless pipe and tube under B622, welded pipe under B619, welded tube under B626. The ASME versions carry the same numbers with an SB prefix.
At what temperature is UNS N06007 forged?
Forging starts around 1150 °C. Stop and reheat before the workpiece drops below about 930 °C. After forging, the part is solution annealed at 1150 to 1180 °C and quenched rapidly to hold carbides in solution.
Can UNS N06007 be age hardened?
No. Alloy G is a solid-solution grade with no precipitation hardening elements to age. It can only be strengthened by cold work. Forgings are supplied solution annealed, and an aging cycle would add cost while risking carbide precipitation and lower corrosion resistance.
What is the difference between N06007, N06985 (G-3) and N06030 (G-30)?
All three are nickel-chromium-iron-molybdenum-copper alloys from the same family. N06007, Alloy G, is the original grade and carries about 2 % niobium plus tantalum as a carbide stabilizer. N06985, Alloy G-3, cuts carbon and niobium and lifts molybdenum a little, which improves corrosion resistance in the weld heat-affected zone; it has largely replaced Alloy G in new construction. N06030, Alloy G-30, raises chromium to around 30 % for better performance in strongly oxidizing media. N06007 is mostly bought today for replacement parts in existing plant, or where a drawing names it.
Is UNS N06007 magnetic?
No. In the solution annealed condition the alloy is single-phase austenitic and non-magnetic. That rules out magnetic particle inspection, so surface NDT is done by liquid penetrant instead.
Who manufactures UNS N06007 forgings?
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory in Jiangyin, Jiangsu Province, China that makes UNS N06007 (Hastelloy G) forgings to customer drawings: seamless rolled rings, flanges, shafts, discs, sleeves, bushings, tube sheets and bars. The works is at No. 1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China. Contact: +86 189 2135 9659, sales@steelforgepieces.com.
What certificates and inspection come with the forgings?
EN 10204 3.1 as standard, EN 10204 3.2 with third party witness on request. Ultrasonic testing to EN 10228-3, SEP 1921 or ASTM A388 at the acceptance class on the order. Liquid penetrant to ASTM E165. Intergranular corrosion testing to ASTM G28 when specified, and positive material identification on request. Heat numbers stay traceable from ingot to finished part.
Is there a minimum order quantity for N06007 forgings?
No fixed piece count. Nickel alloy ingot has to be bought against the order, so single prototype pieces and small spare part batches are priced job by job, and larger batches get a better unit price. Send the drawing and quantity and Jiangyin Jiangnan Metal will come back with price and lead time, normally within 24 working hours.
Jiangyin Jiangnan Metal Co., Ltd.
An open-die forging factory in Jiangyin, Jiangsu Province, China. We make forged rings, seamless rolled rings, flanges, shafts, discs, sleeves and bars in carbon steel, alloy steel, tool steel, stainless steel and nickel alloys including UNS N06007, Inconel, Incoloy and Hastelloy grades. Parts are made to customer drawings, heat treated in house, ultrasonically tested and certified to EN 10204 3.1 or 3.2. We ship worldwide from Shanghai and Zhangjiagang.
Address
No. 1 Chengxiqiao Road
Zhouzhuang Town, Jiangyin City
Jiangsu Province, China
Hours
Monday to Saturday
08:30-18:00 China Standard Time, GMT+8
About this datasheet
Published by: Jiangyin Jiangnan Metal Co., Ltd., Jiangyin, Jiangsu, China.
Last reviewed: 29 August 2026.
Scope: UNS N06007 (Alloy G, Hastelloy® G, W.Nr. 2.4618) chemistry, mechanical and physical properties, applicable ASTM and ASME specifications, forging and heat treatment practice, forged product forms and inspection.
Citation:
Jiangyin Jiangnan Metal Co., Ltd. (2026). UNS N06007 (Hastelloy G) Forgings, Technical Data Sheet. https://www.steelforgepieces.com/Nickel-Alloy/UNS-N06007.html
Trademarks: Hastelloy® is a registered trademark of Haynes International, Inc. Inconel® and Incoloy® are registered trademarks of Special Metals Corporation. The names appear here for grade cross reference only and imply no affiliation or endorsement.
Data source: Composition and property limits come from the applicable ASTM specifications and published data for this grade, and are given as a guide to material selection. Figures for any specific delivery are the ones on the mill test certificate issued with the goods. The governing documents are the purchase order and the specification named on it.