§02 Designations and equivalents
Equivalent designations for Inconel 601
Alloy 601 is specified as UNS N06601, Werkstoff 2.4851 and DIN NiCr23Fe. Inconel is a registered trademark of Special Metals Corporation. Material supplied by Jiangyin Jiangnan Metal is certified to the generic UNS and Werkstoff designations.
- UNS number
- N06601
- Werkstoff / EN
- 2.4851
- DIN name
- NiCr23Fe
- Other trade names
- Alloy 601, Nicrofer 6023
- BS / JIS
- NA 49, NCF 601
- Alloy family
- Ni-Cr-Fe with Al
- Strengthening
- Solid solution
- Magnetic
- No
| Product form | ASTM | ASME | Other |
|---|---|---|---|
| Forgings (our scope) | B564 | SB-564 | AMS 5715, DIN 17754 |
| Rod, bar, shapes | B166 | SB-166 | DIN 17752, ISO 9723 |
| Plate, sheet, strip | B168 | SB-168 | AMS 5870, DIN 17750, EN 10095 |
| Seamless pipe and tube | B167 | SB-167 | DIN 17751, ISO 6207 |
| Seamless tube | B163 | SB-163 | — |
| Fittings | B366 | SB-366 | — |
| Ultrasonic examination | A388 | — | EN 10228-3, SEP 1921 |
| Material certificate | — | — | EN 10204 3.1 / 3.2 |
§03 Chemical composition
Inconel 601 chemical composition
Alloy 601 is nominally 60.5% nickel, 23% chromium and 1.35% aluminium, with iron as the balance. The aluminium addition distinguishes 601 from alloy 600 and is responsible for the alumina scale that governs its oxidation behaviour.
| Element | Symbol | Min % | Max % | Nominal % |
|---|---|---|---|---|
| Nickel plus cobalt | Ni | 58.0 | 63.0 | 60.5 |
| Chromium | Cr | 21.0 | 25.0 | 23.0 |
| Aluminium | Al | 1.0 | 1.7 | 1.35 |
| Iron | Fe | Balance | — | 14.1 |
| Carbon | C | — | 0.10 | 0.05 |
| Manganese | Mn | — | 1.00 | 0.30 |
| Silicon | Si | — | 0.50 | 0.20 |
| Copper | Cu | — | 1.00 | 0.20 |
| Sulphur | S | — | 0.015 | 0.003 |
Melting route. Jiangyin Jiangnan Metal melts alloy 601 by EAF with AOD or VOD refining. ESR remelting is available for forgings requiring improved cleanliness, reduced segregation or additional traceability. Heat chemistry is verified by optical emission spectrometry before the billet is released to the press.
§04 Mechanical properties
Mechanical properties of Inconel 601 forgings
In the solution-annealed condition, alloy 601 forgings meet a minimum tensile strength of 550 MPa (80 ksi), a minimum 0.2% proof stress of 205 MPa (30 ksi) and minimum 30% elongation. Production values are normally above these minima.
| Property | Specified min. | Typical forged | Imperial |
|---|---|---|---|
| Tensile strength Rm | 550 MPa | 620 to 760 MPa | 80 ksi min |
| Proof stress Rp0.2 | 205 MPa | 250 to 380 MPa | 30 ksi min |
| Elongation A5 | 30% | 35 to 55% | 30% min |
| Reduction of area | — | 45 to 70% | — |
| Hardness | — | 130 to 200 HB | 95 HRB max |
| Charpy V impact at 20 °C | — | 100 J min | 74 ft lb |
Elevated-temperature short-time tensile properties
Alloy 601 retains useful strength above the working range of austenitic stainless steels. Proof stress decays slowly between 600 °C and 800 °C, which covers the operating band of most furnace and petrochemical hardware.
| Temp. °C | Temp. °F | Rm MPa | Rp0.2 MPa | Elong. % |
|---|---|---|---|---|
| 20 | 68 | 690 | 300 | 48 |
| 200 | 392 | 640 | 245 | 50 |
| 400 | 752 | 610 | 215 | 52 |
| 600 | 1112 | 570 | 200 | 55 |
| 700 | 1292 | 440 | 195 | 60 |
| 800 | 1472 | 270 | 180 | 75 |
| 900 | 1652 | 150 | 120 | 90 |
| 1000 | 1832 | 80 | 65 | 100 |
Basis of the values above. Table 4 lists typical reference values compiled from published alloy 601 literature. They are not guaranteed minima. Results vary with composition within the specification band, forging reduction ratio, section size and annealing practice. Certified results for a specific heat are stated on the EN 10204 certificate issued with the order.
§05 Physical properties
Inconel 601 physical properties
The density of alloy 601 is 8.11 g/cm³ and the melting range is 1360 to 1411 °C. Use the density figure to convert finished-part volume into forging weight when preparing an enquiry.
| Property | Metric | Imperial |
|---|---|---|
| Density | 8.11 g/cm³ | 0.293 lb/in³ |
| Melting range | 1360 to 1411 °C | 2480 to 2571 °F |
| Modulus of elasticity | 206 GPa | 29.9 x 10³ ksi |
| Specific heat | 448 J/kg·°C | 0.107 Btu/lb·°F |
| Thermal conductivity | 11.2 W/m·°C | 77.7 Btu·in/ft²·h·°F |
| Mean expansion 20 to 540 °C | 15.1 µm/m·°C | 8.4 µin/in·°F |
| Electrical resistivity | 1.19 µΩ·m | 119 µΩ·cm |
| Curie temperature | below −190 °C | below −310 °F |
| Magnetic permeability | 1.003 at 200 Oe | — |
§06 Forged product range
Forged shapes available in Inconel 601
Alloy 601 is produced as open-die forgings and seamless rolled rings in single-piece weights from 5 kg to 15,000 kg. Standard size ranges are listed below. Sizes outside these ranges are quoted on enquiry, as the governing limit is normally the die set and annealing furnace rather than press capacity.
| Forged form | Size range | Weight per piece | Typical application |
|---|---|---|---|
| Seamless rolled rings | OD 200 to 3000 mm, H to 1000 mm | 15 to 12,000 kg | Retort flanges, tower shell rings |
| Forged flanges | DN 15 to DN 2000, to Class 2500 | 2 to 4,000 kg | Reactor and header connections |
| Round bars and billets | Dia. 80 to 1200 mm, L to 8000 mm | 10 to 15,000 kg | Machining stock, valve stems |
| Shafts and spindles | Dia. 80 to 900 mm, L to 8000 mm | 20 to 10,000 kg | Furnace roll shafts, fan shafts |
| Discs and blanks | Dia. 150 to 2200 mm, T 30 to 600 mm | 10 to 9,000 kg | Tube sheets, blind covers |
| Sleeves and bushings | OD 100 to 1500 mm, ID from 60 mm | 5 to 6,000 kg | Bearing housings, wear sleeves |
| Hollow and trepanned bars | OD 150 to 1200 mm, ID from 60 mm | 15 to 8,000 kg | Pressure sleeves, nozzle bodies |
| Tube sheets and plates | To 2200 mm across, T to 600 mm | 25 to 9,000 kg | Shell and tube exchangers |
| Valve bodies and blocks | Per drawing | 5 to 5,000 kg | Ball, gate, globe, check valves |
| Nozzles and step shafts | Per drawing | 5 to 4,000 kg | Burner nozzles, flare tips |
Delivery condition and machining allowance
Forgings are supplied in one of four conditions. Delivery condition affects both price and lead time.
- As forged, black. No machining. For customers performing all machining in house.
- Solution annealed and descaled. Standard delivery condition for alloy 601.
- Rough machined. Typically 3 to 6 mm stock per surface, allowing ultrasonic examination on a machined surface.
- Finish machined to drawing. Tolerances to ISO 2768-m or tighter. 2D or 3D files required.
§07 Manufacturing route
How Inconel 601 forgings are manufactured
Production follows six controlled stages: melting, billet preparation, heating, open-die forging between 870 °C and 1230 °C, solution annealing at 1100 to 1180 °C with rapid cooling, and non-destructive examination with certification.
| Step | Operation | Parameters | Verification |
|---|---|---|---|
| 1 | Melting | EAF with AOD or VOD, optional ESR remelt | OES heat analysis against ASTM B166 limits |
| 2 | Billet preparation | Ingot cropped, surface conditioned, degreased | Visual and dimensional |
| 3 | Heating | Charge below 800 °C, soak to 1200 to 1230 °C, hold by section | Furnace survey, AMS 2750 pyrometry |
| 4 | Open-die forging | Heavy reduction 1040 to 1230 °C, finish passes 870 to 1040 °C, ratio 4:1 or higher | Press log, reduction ratio record |
| 5 | Solution annealing | 1100 to 1180 °C, hold 30 to 60 min, water quench or rapid air cool | Furnace chart, hardness check |
| 6 | Examination and release | 100% UT, PT or MT and PMI on request | ASTM A388, EN 10228-3, SEP 1921 |
Heat treatment of alloy 601. Alloy 601 is solid-solution strengthened and cannot be age-hardened. Supplier literature sometimes describes a combined solution treatment and ageing cycle for this grade. That practice belongs to precipitation-hardening alloys such as Inconel 718, X-750 and Waspaloy, and produces no strength increase in alloy 601. Select either annealing near 1050 to 1100 °C, which gives finer grain and the best tensile properties below 540 °C, or solution treatment near 1150 °C, which gives coarser grain and better creep-rupture life above 540 °C.
Sulphur control during forging
Nickel-rich alloys form a low-melting nickel sulphide eutectic at the grain boundaries at forging temperature, which causes hot tearing. Billets are degreased before charging and only sulphur-free fuel or electric heating is used. For the same reason alloy 601 is not recommended for service in strongly sulphidising atmospheres, despite its oxidation resistance.
§08 Grade selection
Inconel 601 compared with alloys 600, 617, 625 and 800H
Alloy 601 is selected for high-temperature oxidation and thermal cycling. Alloy 625 is selected for aqueous and chloride corrosion. Alloys 617 and 800H are selected where creep-rupture life above 900 °C governs the design.
| Alloy | UNS | Ni / Cr % | Strengthening | Max oxidising | Best when |
|---|---|---|---|---|---|
| Inconel 601 | N06601 | 60.5 / 23 plus 1.35 Al | Solid solution | 1204 °C | Cyclic oxidation, carburising, nitriding |
| Inconel 600 | N06600 | 76 / 15.5 | Solid solution | 1095 °C | Chloride SCC risk, milder oxidation |
| Inconel 617 | N06617 | 54 / 22 plus Co, Mo | Solid solution | 1100 °C | Creep strength above 900 °C governs |
| Inconel 625 | N06625 | 58 / 21.5 plus Mo, Nb | Solid solution | 980 °C | Seawater, acid, pitting or crevice attack |
| Incoloy 800H | N08810 | 32 / 21 | Solid solution | 1000 °C | Cost-driven duty below 900 °C |
| Inconel 718 | N07718 | 53 / 19 plus Nb | Precipitation | 650 °C | High strength below 700 °C |
The difference between alloys 600 and 601 is the aluminium content. Both are Ni-Cr-Fe, but the 1.0 to 1.7% Al in alloy 601 produces an alumina scale that remains adherent through thermal cycling, whereas the chromia scale on alloy 600 tends to spall under repeated heating and cooling. For components subject to daily heat-up and cool-down cycles above 1000 °C, this is the governing selection criterion.
§09 Applications
Where Inconel 601 forgings are used
Alloy 601 forgings are used in thermal processing equipment, petrochemical process hardware, power generation and waste incineration, where components are repeatedly heated in oxidising atmospheres.
| Industry | Forged components | Service condition |
|---|---|---|
| Heat treating | Retort flanges, muffle rings, basket and tray frames, radiant tube supports, fixture shafts | 700 to 1150 °C, cyclic |
| Petrochemical and refining | Catalyst regenerator internals, flare tip rings, burner nozzles, transfer line flanges | 600 to 1050 °C, oxidising |
| Power generation | Superheater tube supports, grid barriers, gas turbine exhaust rings, coal gasifier parts | 550 to 1000 °C |
| Waste to energy | Grate bar carriers, furnace hangers, ash handling sleeves | Cyclic, ash laden |
| Chemical process plant | Reactor flanges, tower shell rings, tube sheets, nozzle forgings, pump shafts | Elevated temp. with corrosion |
| Furnace and kiln builders | Rolled rings for shells, roller shafts, hearth plate supports | Continuous 900 to 1100 °C |
| Valves and flow control | Valve bodies, seat rings, stems and discs for high-temperature service | To 1000 °C |
| Aerospace ground support | Test cell exhaust rings, combustion rig hardware | Short duration extreme |
§10 Machining and welding
Machining and welding of Inconel 601
Alloy 601 is a class C machining alloy. It work-hardens rapidly and requires rigid setups, sharp tooling, reduced cutting speeds and positive feed. It is weldable by GTAW, GMAW, SMAW and SAW without preheat and without mandatory post-weld heat treatment.
Machining
- Maintain continuous feed. A tool rubbing without cutting work-hardens the surface and causes chatter on the following pass.
- Use cutting speeds of approximately 30 to 50% of those applied to 304 stainless steel, with increased depth of cut to work below the hardened layer.
- Use rigid machines, short tool overhangs, sharp positive-rake carbide and flood coolant.
- Remove sulphurised cutting oils completely before any heat treatment.
- The material machines best in the cold-drawn, or cold-drawn and stress-relieved, condition.
Welding
| Item | Recommendation |
|---|---|
| Processes | GTAW (TIG), GMAW (MIG), SMAW, SAW |
| Filler metal | ERNiCrFe-11 or ERNiCr-3. Electrodes to AWS A5.11, wire to AWS A5.14 or EN ISO 18274 |
| Shielding gas | Argon 99.999%, with root purge on full-penetration welds |
| Preheat | Not required. 50 to 100 °C on sections over 50 mm to reduce thermal gradient |
| Interpass temperature | 177 °C (350 °F) maximum |
| Joint cleanliness | Degrease and clean to bare metal 25 mm each side immediately before welding |
| Post-weld heat treatment | Not mandatory. For severe corrosive service, full solution anneal at 1100 to 1180 °C and quench |
§11 Testing and certification
Testing and certification
Inconel 601 forgings are supplied with an EN 10204 3.1 mill test certificate as standard and 100% ultrasonic examination to ASTM A388 or EN 10228-3. EN 10204 3.2 with third-party witness by TUV, SGS, BV or Lloyd's Register is available on request.
| Test | Standard | Scope |
|---|---|---|
| Chemical analysis | ASTM E1473, OES | Every heat |
| Tensile test | ASTM A370, ISO 6892-1 | Every heat treatment lot |
| Hardness | ASTM E10, E18 | Every lot |
| Ultrasonic examination | ASTM A388, EN 10228-3, SEP 1921 | 100% of forgings |
| Liquid penetrant | ASTM E165, EN 10228-2 | On request |
| Grain size | ASTM E112 | On request |
| Intergranular corrosion | ASTM G28 method A | On request |
| Impact test | ASTM E23, ISO 148-1 | On request |
| Positive material identification | XRF | On request |
| Certificate | EN 10204 3.1 / 3.2 | 3.1 standard, 3.2 on request |
Documentation. Melting traceability, furnace pyrometry records and NDE operator qualification are documented for each order. Copies are issued with the quotation on request.
§12 Ordering
Information required for a quotation
The six items below are required to price an alloy 601 forging. Send them to sales@steelforgepieces.com. Quotations are issued within 24 hours on working days.
| Item | Provide | Example |
|---|---|---|
| 1 | Shape and dimensions | Rolled ring, OD 980 x ID 720 x H 260 mm, or attach a PDF or STEP drawing |
| 2 | Quantity and schedule | 6 pcs, split delivery over two months |
| 3 | Delivery condition | Solution annealed and rough machined, 4 mm allowance |
| 4 | Specification | ASTM B564 UNS N06601 |
| 5 | Certificate and NDE | EN 10204 3.1, UT to EN 10228-3 class 3 |
| 6 | Destination and terms | FOB Shanghai or CIF Rotterdam |
- Minimum order
- 1 piece
- Typical lead time
- 25 to 45 days
- Quotation
- Within 24 h
- Ports
- Shanghai, Ningbo
- Incoterms
- EXW, FOB, CIF, DDP
- Drawing formats
- PDF, DWG, STEP, IGES
§13 Frequently asked questions
Inconel 601 forging FAQ
What is Inconel 601 used for?
Inconel 601 is used for components that resist oxidation and thermal cycling at high temperature. Typical items are heat-treating retorts, muffles, baskets and fixtures, radiant tube and superheater supports, petrochemical catalyst regenerator internals, flare tips and burner nozzles, gas turbine exhaust hardware, and waste incineration furnace parts. In forged form it is normally supplied as rolled rings, flanges, tube sheets, shafts and valve components.
What is the maximum service temperature of Inconel 601?
Alloy 601 resists oxidation to approximately 1204 °C (2200 °F). This is an oxidation limit, not a structural limit. Mechanical strength falls sharply above about 900 °C, so load-bearing designs are normally restricted to 950 to 1100 °C depending on stress and required life. For continuous creep-loaded service above 900 °C, alloy 617 or 800H is usually the better choice.
What is the difference between Inconel 600 and Inconel 601?
The aluminium content. Alloy 601 contains 1.0 to 1.7% Al and about 23% Cr. Alloy 600 has no deliberate aluminium addition and about 15.5% Cr. The aluminium in 601 forms an adherent alumina scale that survives repeated heating and cooling, which gives better cyclic oxidation and nitriding resistance. Alloy 600 has higher nickel, about 76%, and is preferred where chloride stress corrosion cracking is the main risk.
Can Inconel 601 be heat treated to increase strength?
No. Alloy 601 is solid-solution strengthened and cannot be age-hardened or precipitation-hardened. Heat treatment selects grain size and property balance, not strength level. Annealing near 1050 to 1100 °C gives finer grain and the best tensile properties below 540 °C. Solution treatment near 1150 °C produces coarser grain and better creep-rupture life above 540 °C. Strength can be raised only by cold work, which is lost on the next anneal.
What is the forging temperature of Inconel 601?
Alloy 601 is hot worked between 870 °C and 1230 °C (1600 to 2250 °F). Heavy reduction is carried out from 1040 to 1230 °C. Finishing passes run in the 870 to 1040 °C band to control grain size. The billet must be clean and free of sulphur-bearing contamination before heating, and forging should stop before the metal falls below 870 °C to avoid cracking.
Which standard covers Inconel 601 forgings?
ASTM B564 and ASME SB-564 cover nickel alloy forgings including UNS N06601. AMS 5715 covers bar, forgings and rings. DIN 17754 is the German equivalent. Bar stock for forging is normally purchased to ASTM B166. Ultrasonic acceptance is usually agreed to ASTM A388, EN 10228-3 or SEP 1921.
Is Inconel 601 magnetic?
No. Alloy 601 is austenitic and effectively non-magnetic at room temperature, with a relative permeability of about 1.003 at 200 oersteds. Its Curie temperature is below minus 190 °C, so it remains non-magnetic through all normal service and cryogenic handling.
Can Inconel 601 be used in sulphur-containing atmospheres?
It is not recommended. Nickel-rich alloys form low-melting nickel sulphide eutectics that attack grain boundaries, so alloy 601 performs poorly in strongly sulphidising service despite its oxidation resistance. Sulphur contamination must also be excluded during forging, heat treatment and machining. Remove sulphurised cutting oils and marking materials before any furnace cycle.
What is the density of Inconel 601 and how is forging weight estimated?
The density is 8.11 g/cm³ (0.293 lb/in³). To estimate a forging weight, calculate the enveloping volume of the rough shape including machining allowance and multiply by 8.11 g/cm³. For example, a solid alloy 601 disc of 500 mm diameter and 100 mm thickness has a volume of about 19,635 cm³ and weighs approximately 159 kg.
What is the minimum order quantity and lead time?
Jiangyin Jiangnan Metal accepts single-piece orders, so one prototype forging is acceptable. Typical lead time is 25 to 45 days depending on size, delivery condition and raw material availability. Quotations are issued within 24 hours on working days from sales@steelforgepieces.com or 0086-189-2135-9659.
Can alloy 601 be ordered under the UNS designation instead of the trade name?
Yes, and this is the correct way to place the order. Inconel is a registered trademark of Special Metals Corporation. Material is supplied and certified to the generic designations UNS N06601, W.Nr. 2.4851 and NiCr23Fe, against ASTM B564 or the equivalent standard named in the purchase order.
What is the largest Inconel 601 forging you can make?
Single-piece forgings up to approximately 15,000 kg, with rolled rings to 3000 mm outside diameter and bars or shafts to 8000 mm long. Parts near the top of that envelope should be discussed before drawing release, as the practical limit is normally the die set and annealing furnace rather than press capacity.
§14 Manufacturer
About Jiangyin Jiangnan Metal Co., Ltd.
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory at No. 1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, approximately 150 km from the Port of Shanghai. The plant produces open-die forgings and seamless rolled rings in carbon steel, alloy steel, tool steel, stainless steel and nickel-based alloys including 601, 600, 625, 718, X-750, Hastelloy and Incoloy grades.
Orders are quoted from drawings or from written dimensional descriptions, in single pieces or production batches, and shipped worldwide through Shanghai and Ningbo. Enquiries are handled in English and Chinese.
- Company
- Jiangyin Jiangnan Metal
- Type
- Open-die forging factory
- Location
- Jiangyin, Jiangsu, China
- Telephone
- +86 189 2135 9659
- Serves
- Worldwide
Reference
Jiangyin Jiangnan Metal Co., Ltd. (2026). Inconel 601 Forgings: Alloy 601 / UNS N06601 Technical Data and Forged Product Range. Jiangyin, Jiangsu, China. www.steelforgepieces.com/Nickel-Alloy/Inconel-601.html
§16 Data sources
Basis of the data on this page
Composition and specification limits follow ASTM B166, B168 and B564 for UNS N06601. Physical constants, forging ranges and annealing ranges follow published producer data for alloy 601 and DIN EN 10095. Typical mechanical values are compiled from that literature and compared against production test results. Values described as typical are for engineering reference and preliminary design. Certified values for a given order are those stated on its EN 10204 certificate. Inconel, Incoloy, Nimonic and Hastelloy are registered trademarks of their respective owners and are used to identify alloy grades.