Jiangyin Jiangnan MetalUNS N06030 overview
UNS N06030 is a nickel-chromium-iron-molybdenum alloy, also sold as Alloy G-30, Hastelloy® G-30® and Werkstoff 2.4603. It contains 28.0–31.5 % chromium, 4.0–6.0 % molybdenum, 13.0–17.0 % iron, 1.0–2.4 % copper and 1.5–4.0 % tungsten, with nickel as the balance. It was developed as a higher-chromium replacement for Alloy G-3 (UNS N06985) in wet-process phosphoric acid service.
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China. We forge UNS N06030 into seamless rolled rings, flanges, round bars, discs, sleeves, bushings, tube sheets, spindles and shafts to ASTM B462 and ASTM B564, adopted by ASME as SB-462 and SB-564. Parts are supplied solution annealed at 1177 °C with rapid quench, ultrasonically tested to EN 10228-3, SEP 1921 or ASTM A388, and certified to EN 10204 3.1 or 3.2. For quotations contact sales@steelforgepieces.com or +86 189 2135 9659.
N06030 is used where the process chemistry is oxidising enough to attack stainless steel but does not require a high-molybdenum alloy such as C-276. Its chromium content is the highest in the Hastelloy® G family, and that is what makes it suitable for commercial wet-process phosphoric acid (P2O5), the route used to produce most phosphate fertiliser. Copper and molybdenum give the alloy some tolerance of reducing acids. The carbon maximum of 0.03 % limits carbide precipitation in the weld heat-affected zone, so most fabrications are put into service as welded.
Chromium
The highest chromium level in the G family, and the reason N06030 performs better than G-3 in phosphoric and nitric acid.
Solution anneal
Followed by water quench. N06030 is a solid-solution alloy and is not age hardened.
Minimum UTS
85 ksi minimum, with 241 MPa (35 ksi) yield and 30 % elongation in the annealed condition.
Density, g/cm³
0.297 lb/in³, used for forging weight and piping stress calculations.
UNS N06030 equivalents and standards
The alloy appears on drawings under several names. Each designation below refers to the same material.
| System | Designation | Notes |
|---|---|---|
| UNS | N06030 | Sometimes written NO6030 on older drawings. The second character is a zero. |
| Werkstoff (DIN) | 2.4603 | German material number. |
| EN chemical name | NiCr30FeMo | Descriptive EN designation. |
| Trade names | Hastelloy® G-30®, Haynes® G-30® | Registered trademarks of Haynes International, Inc. |
| Forgings, flanges, fittings | ASTM B462 / ASME SB-462 | Forged or rolled flanges, fittings, valves and parts for high-temperature service. |
| Forgings | ASTM B564 / ASME SB-564 | Nickel alloy forgings. The usual specification for rings, discs, shafts and blanks. |
| Rod, bar, wire | ASTM B581 | Source of the room-temperature mechanical minima given below. |
| Plate, sheet, strip | ASTM B582 | For fabricated vessel sections. |
| Seamless pipe & tube | ASTM B622 | Welded equivalents are B619 for pipe and B626 for tube. |
| Welding consumables | AWS A5.11 ENiCrMo-11 AWS A5.14 ERNiCrMo-11 | Covered electrode and bare wire matching N06030. |
Standards are revised periodically. Please confirm the edition and year called out on your purchase specification. We manufacture to the revision you nominate.
Chemical composition of UNS N06030
Composition limits in weight percent to ASTM B462, B564 and B581. Every heat is verified by spectrographic analysis before release. Positive material identification on the finished part is available on request.
| Element | Min | Max | Function |
|---|---|---|---|
| Chromium, Cr | 28.0 | 31.5 | Resistance to phosphoric, nitric and other oxidising acids. |
| Nickel, Ni | Balance (≈ 40) | Austenitic matrix. Reduces the risk of chloride stress-corrosion cracking. | |
| Iron, Fe | 13.0 | 17.0 | Deliberate addition that keeps cost below fully nickel-based grades. |
| Molybdenum, Mo | 4.0 | 6.0 | Moderate resistance to reducing acids and pitting. |
| Tungsten, W | 1.5 | 4.0 | Solid-solution strengthening. Supports localised corrosion resistance. |
| Copper, Cu | 1.0 | 2.4 | Improves behaviour in sulphuric and phosphoric acid. |
| Niobium + tantalum, Cb+Ta | 0.30 | 1.50 | Stabilises carbon and protects the weld heat-affected zone. |
| Cobalt, Co | — | 5.0 | Residual limit. Nuclear purchasers often cap this much lower. |
| Manganese, Mn | — | 1.5 | Deoxidiser. |
| Silicon, Si | — | 0.80 | Deoxidiser. |
| Carbon, C | — | 0.03 | Low ceiling, which is why N06030 can be welded without post-weld annealing. |
| Phosphorus, P | — | 0.04 | Residual. |
| Sulphur, S | — | 0.02 | Residual, kept low for hot workability. |
Ordering note. Cobalt and carbon are the limits most often tightened on customer specifications. Nuclear work typically caps cobalt at 0.20 % or 0.05 %. Please send any restricted limits with your enquiry so that we can reserve a suitable heat before quoting.
Mechanical properties of UNS N06030 forgings
ASTM minimum values and typical test results for solution-annealed material. Design to the minimum values. The mill certificate gives the actual figures for the heat supplied.
| Property | ASTM minimum | Typical | Test method |
|---|---|---|---|
| Tensile strength, Rm | 586 MPa · 85 ksi | ≈ 690 MPa · 100 ksi | ASTM E8 / ISO 6892-1 |
| Yield strength, Rp0.2 | 241 MPa · 35 ksi | ≈ 317 MPa · 46 ksi | ASTM E8 / ISO 6892-1 |
| Elongation, A5 | 30 % | ≈ 55–65 % | ASTM E8 |
| Hardness | — | ≈ 84 HRB · 165 HB | ASTM E18 / E10 |
| Impact, Charpy V (RT) | By agreement | High, fully austenitic | ASTM E23 / ISO 148-1 |
| Sour-service hardness cap | ≤ 22 HRC | Met as annealed | NACE MR0175 / ISO 15156-3 |
Forged compared with machined from bar
An open-die forged ring or disc has grain flow that follows the part contour, while a component machined from plate or large bar cuts across the flow lines. On pressure-retaining nickel alloy parts this affects through-thickness consistency and ultrasonic cleanliness. Our N06030 forgings are upset and drawn to a controlled forging ratio and re-solution-annealed after the last hot working operation, which this alloy requires.
Physical properties
Design values for heat-exchanger sizing, piping thermal-stress analysis and forging weight estimation.
| Property | Metric | Imperial |
|---|---|---|
| Density | 8.22 g/cm³ | 0.297 lb/in³ |
| Melting range (approx.) | 1225–1345 °C | 2240–2450 °F |
| Modulus of elasticity | ≈ 199 GPa | ≈ 28.9 × 10³ ksi |
| Thermal conductivity | ≈ 10.2 W/m·K | ≈ 71 Btu·in/h·ft²·°F |
| Mean thermal expansion, 20–100 °C | ≈ 12.5 × 10⁻⁶ /K | ≈ 6.9 × 10⁻⁶ /°F |
| Electrical resistivity | ≈ 1.16 µΩ·m | ≈ 700 Ω·circ mil/ft |
| Specific heat | ≈ 435 J/kg·K | ≈ 0.104 Btu/lb·°F |
| Magnetic permeability | ≈ 1.001, effectively non-magnetic | |
Physical properties are typical published values for the alloy and are given for design guidance. They are not a contractual guarantee. The mill certificate issued with the forging governs.
Forging and heat treatment of UNS N06030
N06030 is a solid-solution alloy. Its strength comes from chromium, molybdenum and tungsten held in solution rather than from precipitation, so it is solution annealed and quenched and is never aged. Specifications that call for an ageing cycle on N06030 have usually been copied from a precipitation-hardening grade such as Inconel® 718 or Incoloy® 925, and we will raise a query before manufacture.
| Operation | Temperature | Practice |
|---|---|---|
| Hot working range | 1050–1200 °C 1920–2190 °F | Narrow. The alloy is more sensitive to strain and strain rate than austenitic stainless steel, so press forging with controlled reduction gives better results than hammer work. |
| Finish forging above | ≈ 950 °C · 1740 °F | Stop deforming before the piece drops out of the window and reheat instead of continuing. |
| Solution anneal | 1177 °C · 2150 °F | Hold 10 to 30 minutes depending on section thickness, the full 30 minutes for heavy sections. |
| Quench | — | Water quench is advised. Rapid air cooling is acceptable only for sections thinner than about 10 mm (0.375 in). |
| Re-anneal after | — | All hot forming, and any cold forming that produces 7 % or more outer-fibre elongation. |
| Post-weld heat treatment | — | Usually not required. The alloy resists grain-boundary precipitation in the heat-affected zone and is normally used as welded. |
Welding
N06030 welds readily by GTAW, GMAW and SMAW with matching consumables: AWS A5.14 ERNiCrMo-11 wire or AWS A5.11 ENiCrMo-11 covered electrode. Keep heat input and interpass temperature low, clean the joint thoroughly and avoid weaving. Because the alloy resists heat-affected-zone carbide precipitation, weldments generally go into acid service without a post-weld solution anneal. This is a useful fabrication advantage over the older Alloy G.
Corrosion behaviour and alloy selection
N06030 was developed around one application: commercial wet-process phosphoric acid, produced by digesting phosphate rock in sulphuric acid. That stream carries fluorides, chlorides and abrasive solids, and it attacks most stainless steels in evaporator service. The chromium content deals with the oxidising attack, molybdenum and copper cover the reducing component, and the nickel content limits chloride stress-corrosion cracking.
Main applications
Wet-process phosphoric acid (P2O5), nitric acid and nitric mixtures, nitric/HF and nitric/HCl pickling, oxidising salts, and chloride-bearing acid streams where stainless steel fails by stress-corrosion cracking.
Moderate service
Sulphuric and hydrochloric acid at moderate strength, helped by the molybdenum and copper additions. Alloy 625 is slightly better in sulphuric acid, and C-276 is better still under strongly reducing conditions.
Not suitable
Hot concentrated hydrochloric acid and strongly reducing service, where Hastelloy® B-2, B-3 or C-276 should be specified. High-temperature structural creep service, where Alloy 617, 625 or 800HT is the usual choice.
| Grade | Cr % | Mo % | Normally specified for |
|---|---|---|---|
| UNS N06030 (G-30) | 28.0–31.5 | 4.0–6.0 | Wet-process phosphoric acid, nitric and mixed oxidising acids, pickling lines. |
| UNS N06985 (G-3) | 21.0–23.5 | 6.0–8.0 | The predecessor grade. More molybdenum and less chromium, so better in reducing and weaker in oxidising conditions. |
| UNS N10276 (C-276) | 14.5–16.5 | 15.0–17.0 | Strongly reducing service, hot hydrochloric acid, mixed acids with chlorides and pitting risk. |
| UNS N06625 (Alloy 625) | 20.0–23.0 | 8.0–10.0 | Seawater, sour service, general chemical duty, elevated-temperature strength. |
| UNS N08825 (Alloy 825) | 19.5–23.5 | 2.5–3.5 | Sulphuric and phosphoric acid at lower severity, at lower cost than N06030. |
Composition ranges are taken from the respective ASTM specifications and are given for selection guidance. Material selection for a specific process stream should be confirmed by your corrosion engineer against plant conditions.
UNS N06030 forgings we supply
All items are made to drawing or dimensional sketch. We do not hold stock in this grade. Parts are supplied rough machined with forging allowance, or finish machined to print.
| Product form | Typical size range | Common use |
|---|---|---|
| Seamless rolled rings | OD 200–3000 mm Wall 20–400 mm · Height ≤ 800 mm | Vessel shell courses, valve seat rings, bearing races |
| Forged flanges | DN 15–DN 2000 ASME B16.5 / B16.47 / EN 1092-1 | WN, SO, BL, LJ, orifice, within ASTM B462 scope |
| Round bars & billets | Ø 30–800 mm · L ≤ 6000 mm | Machining stock, valve stems, fastener stock |
| Discs & blanks | Ø ≤ 2000 mm · T 20–500 mm | Blind covers, valve discs, closure heads |
| Sleeves & bushings | OD 100–1200 mm | Pump wear parts, agitator bushings |
| Tube sheets | Ø ≤ 2500 mm · T ≤ 400 mm | Shell-and-tube heat exchangers, P₂O₅ evaporators |
| Shafts & spindles | Ø 50–800 mm · L ≤ 6000 mm | Chemical pumps, agitators, plunger pumps |
| Hollow forgings / forged tube | OD 150–1500 mm | Nozzles, valve bodies, pressure-vessel connections |
| Valve components | To drawing | Bodies, bonnets, seat rings, stems, gate and plug parts |
| Single-piece weight | 5 kg – 5000 kg | Heavier pieces quoted case by case |
The ranges above cover the work we do regularly. If a part falls outside them, send the drawing and we will confirm whether we can make it.
Manufacturing route for an N06030 forging
Every nickel alloy order runs through the route below at our works in Zhouzhuang Town, Jiangyin. Hold points can be added at any stage for your inspector or a third-party agency.
- Melt and refine the heatElectric arc furnace with AOD or VOD refining, or vacuum induction melting, followed by electroslag remelting or vacuum arc remelting where the specification calls for it. Ladle analysis is checked against your restricted limits before the ingot is released.
- Ingot heating and coggingSoaked into the 1050 to 1200 °C working window, then upset and drawn to break down the cast structure. Reheats are planned in advance because the working window for this alloy is narrow and it will crack if worked too cold.
- Open-die forging or ring rollingHydraulic press forging to the drawing, or radial-axial ring rolling for seamless rings, with the forging ratio recorded on the traveller.
- Solution anneal and quench1177 °C, held 10 to 30 minutes according to section thickness, then water quenched. Furnace charts are retained and issued with the certificate.
- Rough or finish machiningTurning, boring, drilling and milling in-house, either to forging allowance or to final print tolerance.
- Testing and NDTMechanical testing, hardness, positive material identification, ultrasonic examination, and where required dye penetrant, intergranular corrosion testing and dimensional inspection.
- Certification, marking and packingEN 10204 3.1 or 3.2 certificate, hard stamping or vibro-marking of heat number and grade, and seaworthy packing with photographs taken before the container is sealed.
Testing and certification
Ultrasonic examination
To EN 10228-3, SEP 1921 or ASTM A388. Nominate the standard and acceptance class on the order and it is applied to the finished forging.
Chemical verification
Spectrographic ladle and product analysis, with positive material identification on the finished part on request.
Mechanical testing
Tensile, hardness and Charpy impact taken from a test coupon heat-treated with the parts.
Corrosion testing
Intergranular corrosion testing to ASTM G28 method A where the specification requires it.
Certification
EN 10204 3.1 as standard, or 3.2 with third-party endorsement by SGS, BV, TÜV, Lloyd's or your nominated agency.
Sour service
NACE MR0175 / ISO 15156-3 compliance available with hardness controlled to 22 HRC or below.
Quality system. Our forging operation works to a documented quality management system covering material traceability, heat-treatment control and inspection records. Certificate details and a sample mill test certificate are available on request.
Where UNS N06030 forgings are used
Phosphate fertiliser
Evaporator tube sheets, agitator shafts, pump casings, heat-exchanger components and flanges in wet-process phosphoric acid plants.
Metal pickling
Nitric/hydrofluoric and nitric/hydrochloric pickling line hardware, tank internals, rolls and supports for stainless steel processing.
Chemical process
Columns, towers, reactors and pressure-vessel nozzles in nitric acid, mixed-acid and oxidising salt service.
Valves and flow control
Forged bodies, bonnets, seat rings, stems and plugs for ball, gate, globe, check and plug valves handling aggressive acid streams.
Rotating equipment
Chemical pump shafts, plunger pump components, agitator spindles, sleeves and bushings.
Hydrometallurgy and waste
Gold extraction circuits using chloride leach chemistry, and nuclear waste processing equipment where oxidising conditions dominate.
UNS N06030 frequently asked questions
What is UNS N06030?
UNS N06030 is a nickel-chromium-iron-molybdenum corrosion-resistant alloy containing 28.0 to 31.5 % chromium, 4.0 to 6.0 % molybdenum, 13.0 to 17.0 % iron, 1.0 to 2.4 % copper and 1.5 to 4.0 % tungsten, with nickel as the balance. It is commonly called Alloy G-30 and carries the German material number 2.4603. It was developed as a higher-chromium replacement for Alloy G-3 (UNS N06985) in wet-process phosphoric acid service.
Is UNS N06030 the same as Hastelloy G-30?
Yes. They are the same material. UNS N06030 is the standardised number in the Unified Numbering System, while Hastelloy® G-30® and Haynes® G-30® are registered trade names of Haynes International, Inc. for that composition. Jiangyin Jiangnan Metal supplies the alloy to the UNS N06030 chemical and mechanical requirements of ASTM B462 and B564. We are not affiliated with Haynes International and use the trade name only to identify the composition.
Which standards cover UNS N06030 forgings?
For forged products the two governing specifications are ASTM B462, covering forged or rolled flanges, fittings, valves and parts, and ASTM B564, covering nickel alloy forgings. ASME adopts these as SB-462 and SB-564. Related product forms use ASTM B581 for rod and bar, B582 for plate, sheet and strip, B622 for seamless pipe and tube, B619 for welded pipe and B626 for welded tube. Matching welding consumables are AWS A5.11 ENiCrMo-11 and AWS A5.14 ERNiCrMo-11.
What are the minimum mechanical properties of UNS N06030?
In the solution-annealed condition the ASTM minima are a tensile strength of 586 MPa (85 ksi), a 0.2 % offset yield strength of 241 MPa (35 ksi) and 30 % elongation. Actual heats normally test considerably higher, around 690 MPa tensile, 317 MPa yield and 55 to 65 % elongation. Design to the minima and use the mill certificate for the delivered heat.
What heat treatment is applied to UNS N06030 forgings?
Solution annealing at 1177 °C (2150 °F) with a hold of 10 to 30 minutes depending on section thickness, followed by a water quench. Rapid air cooling is acceptable only below roughly 10 mm section. N06030 is a solid-solution alloy and is not age hardened, so any specification calling for an ageing cycle on this grade should be queried before manufacture.
Can UNS N06030 be welded without post-weld heat treatment?
In most cases, yes. The 0.03 % maximum carbon and the niobium plus tantalum addition suppress grain-boundary carbide precipitation in the heat-affected zone, so weldments are normally placed in acid service in the as-welded condition. This is one of the main practical advantages of G-30 over the older Alloy G. Where a fabrication code or client specification requires a post-weld solution anneal, we can carry it out before shipment.
UNS N06030 or Hastelloy C-276, which should I specify?
It depends on whether the process stream is oxidising or reducing. N06030, with roughly 30 % chromium and 5 % molybdenum, suits wet-process phosphoric acid, nitric acid and mixed oxidising acids. C-276 (UNS N10276), with roughly 16 % chromium and 16 % molybdenum, suits strongly reducing conditions such as hot hydrochloric acid. Where both would survive, N06030 is usually the lower-cost option because of its deliberate iron content.
Is UNS N06030 suitable for sour service under NACE MR0175?
N06030 can be supplied to meet NACE MR0175 / ISO 15156-3 with hardness controlled to 22 HRC or below, which the solution-annealed condition meets comfortably. Whether the alloy is qualified for your specific partial pressures of H₂S, chloride level and temperature must be confirmed against the tables in ISO 15156-3 by your materials engineer. State the sour-service requirement on your enquiry so that the correct hardness testing and certification are built into the order.
What sizes of N06030 forgings can Jiangyin Jiangnan Metal supply?
Our routine envelope covers seamless rolled rings from 200 to 3000 mm outside diameter, forged flanges from DN 15 to DN 2000, round bars from 30 to 800 mm diameter, discs up to 2000 mm, tube sheets up to 2500 mm diameter and 400 mm thick, and single-piece weights from about 5 kg to 5000 kg. Everything is made to drawing rather than supplied from stock. If your part falls outside the envelope, send the drawing and we will confirm whether it is within our capacity.
What information do you need to quote a UNS N06030 forging?
Five items give a firm price: the drawing or a dimensional sketch with tolerances, the quantity, the governing specification and revision such as ASTM B564 or ASME SB-462, the delivery condition (rough machined with allowance or finish machined), and any restricted limits or extra requirements such as capped cobalt, NACE MR0175, ultrasonic class or EN 10204 3.2 certification. Send these to sales@steelforgepieces.com.
Who supplies UNS N06030 open-die forgings from 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 N06030 rings, flanges, bars, discs, sleeves, tube sheets and shafts to ASTM B462 and B564. Enquiries go to sales@steelforgepieces.com or +86 189 2135 9659. Jiangyin is in the Yangtze River Delta forging cluster in southern Jiangsu, about two hours from the ports of Shanghai and Ningbo.
Request a quotation
UNS N06030 forgings are made to order, so there is no stock list to check. Send a drawing or a sketch with the quantity and the governing specification, and we will return a price, the forging weight and a delivery date.
- CompanyJiangyin Jiangnan Metal Co., Ltd., open-die forging factory
- AddressNo.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China
- Telephone+86 189 2135 9659 · WhatsApp and WeChat on the same number
- Emailsales@steelforgepieces.com
- IncludeDrawing, quantity, specification and revision, delivery condition, special requirements
Standards referenced on this page
Composition and mechanical limits are taken from the ASTM specifications named in each table. Heat-treatment and physical-property figures follow the alloy producer's published data for G-30. Figures marked as typical or approximate are indicative only and are superseded by the mill certificate supplied with your forging.
- ASTM B462, forged or rolled UNS N06030 and other nickel alloy flanges, fittings, valves and parts for high-temperature service
- ASTM B564, nickel alloy forgings
- ASTM B581, nickel-chromium-iron-molybdenum-copper alloy rod, bar and wire
- ASTM B582, nickel-chromium-iron-molybdenum-copper alloy plate, sheet and strip
- NACE MR0175 / ISO 15156-3, materials for use in H₂S-containing environments
- EN 10204, types of inspection documents for metallic products
- EN 10228-3, SEP 1921 and ASTM A388, ultrasonic examination of forgings
- Haynes International, HASTELLOY® G-30® alloy principal features and heat-treatment data
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