Summary
NCF 601 is a solid-solution nickel-chromium-iron alloy specified in JIS G4901, G4902 and G4903. It contains 58 to 63 % nickel, 21 to 25 % chromium and 1.0 to 1.7 % aluminium. The same alloy is designated UNS N06601 in the United States and 2.4851 (NiCr23Fe) in Germany, and is sold under the trade name Inconel 601. The aluminium content produces an adherent alumina scale, which gives the alloy its resistance to oxidation, carburisation and scaling at temperatures up to about 1150 °C. 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 NCF 601 into rings, seamless rolled rings, shafts, flanges, bars, discs, sleeves, bushings and tube sheets from 20 kg to 30,000 kg per piece.
What NCF 601 is
NCF 601 belongs to the JIS NCF series of heat-resisting and corrosion-resisting alloys. It contains 1.0 to 1.7 % aluminium. At high temperature this aluminium forms an alumina layer beneath the chromium oxide scale. The layer stays keyed to the base metal through repeated heating and cooling, so the alloy does not spall as readily as plain nickel-chromium grades. This is the main reason NCF 601 is specified for radiant tubes, muffles, retorts, furnace fans and other thermal processing components.
NCF 601 also resists carburising and nitriding atmospheres, and it is not subject to chloride stress corrosion cracking in the way austenitic stainless steels are.
Forged NCF 601 has a wrought grain structure. Casting leaves coarse dendrites and segregation, whereas open-die forging with controlled reduction breaks these down and gives a uniform recrystallised grain that responds consistently to ultrasonic inspection. Ring rolling places the grain flow around the circumference of the ring, in the same direction as the hoop stress.
NCF 601 equivalent grades
NCF 601 is listed under a different designation in each standards system. The grades below are the same alloy. We certify forgings to whichever designation appears on your purchase order.
| System | Designation | Product standard |
|---|---|---|
| JIS, Japan | NCF 601 | G4901 bar, G4902 plate and sheet, G4903 seamless pipe |
| UNS, USA | N06601 | ASTM B166 bar, B168 plate, B167 pipe |
| ASME, USA | SB-166 / SB-167 / SB-168 | ASME BPVC Section II Part B |
| Werkstoff, Germany | 2.4851 | VdTUV Wb 470, DIN 17742 / 17750 |
| EN chemical name | NiCr23Fe | EN 10095 heat-resisting alloys |
| AMS, aerospace | AMS 5715, AMS 5870 | Bar; sheet, strip and plate |
| Trade name | Inconel 601 | Trademark of Special Metals Corporation |
| China, approximate | NS3105 | GB/T 15007, cross-reference only, verify before ordering |
Trade names are shown for identification only. Inconel is a registered trademark of Special Metals Corporation. Jiangyin Jiangnan Metal Co., Ltd. is not affiliated with or licensed by that company.
NCF 601 chemical composition
The table gives the specified composition range for NCF 601 and UNS N06601. Ladle and product analysis for the actual heat is stated on the mill certificate supplied with the parts.
| Element | Min % | Max % |
|---|---|---|
| Nickel (Ni) | 58.0 | 63.0 |
| Chromium (Cr) | 21.0 | 25.0 |
| Aluminium (Al) | 1.00 | 1.70 |
| Carbon (C) | - | 0.10 |
| Manganese (Mn) | - | 1.00 |
| Silicon (Si) | - | 0.50 |
| Copper (Cu) | - | 1.00 |
| Sulphur (S) | - | 0.015 |
| Iron (Fe) | Remainder, nominally 13.0 to 17.0 | |
Tighter limits, for example restricted sulphur or a cobalt limit for nuclear service, can be agreed at enquiry stage and written into the heat specification before melting.
NCF 601 mechanical properties
Minimum room temperature properties in the solution annealed condition:
| 0.2 % proof strength (N/mm²) |
Tensile strength (N/mm²) |
Elongation A5 (%) |
Hardness (HB) |
|---|---|---|---|
| min 195 | min 550 | min 30 | max 210 typical |
Hardness is not a specified acceptance value in JIS G4902. The figure shown is the range normally measured on annealed forgings and is reported on the certificate on request. Elevated temperature and stress rupture data for a given section size can be supplied with the quotation.
NCF 601 physical properties
| Property | Value |
|---|---|
| Density | 8.11 g/cm³ (0.293 lb/in³) |
| Melting range | 1360 to 1411 °C |
| Modulus of elasticity | 206 GPa |
| Specific heat | 448 J/(kg·K) |
| Thermal conductivity | 11.3 W/(m·K) |
| Mean coefficient of thermal expansion, 20 to 100 °C | 13.75 µm/(m·K) |
| Electrical resistivity | 1.19 µΩ·m |
| Magnetic permeability at 200 Oe | 1.005, non-magnetic |
| Maximum continuous service temperature | 1150 °C, oxidising atmosphere |
NCF 601 forged shapes supplied
Each item below is open-die forged or ring rolled to your drawing. No die tooling is required, so single pieces and small batches are practical:
- NCF 601 forged rings and seamless rolled rings, with circumferential grain flow
- NCF 601 forged flanges: weld neck, blind, slip on, long weld neck and non-standard patterns
- NCF 601 forged round bars and forged shafts, including stepped and eccentric shafts
- NCF 601 forged discs and disks, hubbed discs and blanks
- NCF 601 forged sleeves, forged bushings and hollow bars
- NCF 601 forged tube sheets and heat exchanger tube plates
- NCF 601 forged valve bodies, valve seat rings, valve stems and blocks
- NCF 601 forged nozzles, forging spindles, gear blanks and rolls
Size and weight range
| Form | Dimensional range | Single-piece weight |
|---|---|---|
| Seamless rolled rings | OD 200 to 4,000 mm, height 60 to 800 mm | 30 to 12,000 kg |
| Forged rings and sleeves | OD 150 to 2,500 mm | 20 to 8,000 kg |
| Bars and shafts | Dia. 80 to 1,200 mm, length to 8,000 mm | 30 to 20,000 kg |
| Discs and blanks | Dia. to 2,500 mm, thickness to 600 mm | 25 to 15,000 kg |
| Flanges and tube sheets | OD to 3,000 mm | 20 to 10,000 kg |
| Blocks and custom shapes | To drawing | to 30,000 kg |
Sizes outside these ranges are often still possible. Send the drawing for confirmation.
Production route
-
Melting
NCF 601 is melted by electric arc furnace with AOD or VOD refining. ESR remelting is added where the application calls for lower inclusion content or reduced segregation, which is normal for pressure retaining and rotating parts.
-
Heating and open-die forging
Ingots and billets are soaked at 1180 to 1220 °C. The working range of the alloy is narrow, so pieces are reheated as required and forging is finished above about 950 °C to avoid cracking and to control grain size.
-
Ring rolling
Ring blanks are upset, punched and rolled to size. This produces continuous circumferential grain flow, which cannot be obtained by machining a ring from plate.
-
Solution annealing
Forgings are solution annealed at 1100 to 1150 °C and cooled rapidly. NCF 601 is a solid-solution alloy and is not precipitation hardened, so no ageing treatment follows.
-
Machining
Forgings are turned or bored to the machining allowance stated on your drawing. Semi-finished and finish machined parts are also supplied.
-
Testing and documentation
Chemical analysis, mechanical testing and non-destructive testing are carried out, and the results are issued as an EN 10204 3.1 or 3.2 document package.
Testing and certificates
- Chemical analysis: ladle and product analysis on every heat
- Mechanical testing: room temperature tensile, elongation, reduction of area and hardness; impact and elevated temperature testing on request
- Ultrasonic testing to EN 10228-3, SEP 1921 or ASTM A388, to the quality class you nominate
- Liquid penetrant testing to ASTM E165 or EN ISO 3452
- Dimensional inspection against your drawing, with a signed report
- Grain size and microstructure to ASTM E112 on request
- Inspection documents: EN 10204 3.1 as standard, EN 10204 3.2 countersigned by SGS, BV, TUV or Lloyd's Register on request
- PED 2014/68/EU material appraisal for European pressure equipment projects
NCF 601 applications by industry
Thermal processing and furnaces
Radiant tubes, muffles, retorts, furnace fans, roller hearth components, baskets and fixtures that cycle repeatedly to high temperature.
Petrochemical and refining
Forged flanges, nozzles, tube sheets and shafts for columns, towers, preheaters, process modules and shell and tube heat exchangers.
Power generation
Rings, shafts and gear blanks for turbines, gas compressors, gearboxes, nitrogen generators and power transmission assemblies.
Pressure vessels
Forged shells, tube sheets, flanges, hollow bars and forged pipe for vessels, air receivers and heat exchangers built to ASME or PED rules.
Valves and flow control
Valve bodies, seat rings, stems and blocks for ball, gate, globe, check and plug valves in high temperature service.
Oil and gas, offshore
Subsea and deepwater production hardware, wellhead and Christmas tree components, manifolds and compressor parts.
Chemical process equipment
Pump shafts and sleeves for chemical and plunger pumps, crystalliser hardware, agitator shafts and mixer components.
Heavy machinery
Forged rolls, wheels, crankshafts and eccentric shafts for cement mills, sugar mills, pulp and paper, shipbuilding and pharmaceutical plant.
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, about 130 km from the Port of Shanghai. We forge rings, seamless rolled rings, shafts, flanges, bars, discs, sleeves, bushings and tube sheets in carbon steel, alloy steel, tool steel, stainless steel and nickel alloys, and supply OEMs, project contractors and stockholders worldwide.
All work is open-die forged rather than closed-die pressed. There is no die cost, so we quote single drawings, small batches and replacement parts for older equipment.
Contact and company details
- Company
- Jiangyin Jiangnan Metal Co., Ltd.
- Business
- Open-die forging factory. Forged rings, shafts, flanges, bars and discs
- Address
- No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China
- Telephone, WhatsApp, WeChat
- +86 189 2135 9659
- sales@steelforgepieces.com
- Website
- www.steelforgepieces.com
- Languages
- English, Chinese
Frequently asked questions
What is NCF 601?
NCF 601 is the Japanese Industrial Standard designation for a solid-solution nickel-chromium-iron alloy containing 58 to 63 percent nickel, 21 to 25 percent chromium and 1.0 to 1.7 percent aluminium. It is covered by JIS G4901 for bars, JIS G4902 for plates and sheets and JIS G4903 for seamless pipes. The aluminium forms an adherent alumina scale, which gives the alloy its resistance to oxidation, carburisation and scaling up to about 1150 °C.
Is NCF 601 the same as Inconel 601?
Yes. NCF 601, UNS N06601, W.Nr. 2.4851, NiCr23Fe and Inconel 601 are the same nickel-chromium-iron alloy under different naming systems. NCF 601 is the JIS designation, N06601 is the UNS number, 2.4851 is the German Werkstoff number, and Inconel 601 is a registered trademark of Special Metals Corporation. Jiangyin Jiangnan Metal Co., Ltd. certifies forgings to whichever designation appears on the purchase order.
What is the maximum service temperature of NCF 601?
NCF 601 is used continuously up to about 1150 °C in oxidising atmospheres. It also performs well under intermittent cyclic heating because the alumina scale stays attached to the base metal through thermal cycling. Above about 1200 °C the alloy retains little useful mechanical strength and is treated as a heat-resisting rather than a load-bearing material.
Which standards cover NCF 601 forgings?
Chemical and mechanical requirements are given in JIS G4901, G4902 and G4903 in Japan, and in ASTM B166 for rod and bar, ASTM B168 for plate and sheet and ASTM B167 for seamless pipe under the equivalent UNS N06601. ASME SB-166, SB-167 and SB-168 apply to pressure vessel work, and AMS 5715 and AMS 5870 apply in aerospace. Ultrasonic testing is normally to EN 10228-3, SEP 1921 or ASTM A388.
What forged shapes can be produced in NCF 601?
Jiangyin Jiangnan Metal Co., Ltd. produces NCF 601 as forged rings, seamless rolled rings, flanges, round bars, shafts, discs, sleeves, bushings, tube sheets, hollow bars, valve bodies, valve seat rings and forged nozzles. All shapes are open-die forged to the customer drawing or to supplied dimensions, so no die tooling cost applies to single pieces or small batches.
In what condition are NCF 601 forgings delivered?
NCF 601 forgings are delivered solution annealed, normally at 1100 to 1150 °C followed by rapid cooling. NCF 601 is a solid-solution alloy and is not precipitation hardened, so no ageing treatment follows. Properties are controlled by forging reduction, finishing temperature and grain size.
What testing and certificates are supplied with NCF 601 forgings?
Jiangyin Jiangnan Metal Co., Ltd. supplies chemical analysis, room temperature tensile and hardness results, ultrasonic testing to EN 10228-3, SEP 1921 or ASTM A388, and liquid penetrant testing to ASTM E165 where required. Documents are issued as EN 10204 3.1 mill certificates, or as EN 10204 3.2 certificates countersigned by a third party such as SGS, BV, TUV or Lloyd's Register.
What is the largest NCF 601 forging you can make?
Single-piece NCF 601 forgings are produced from about 20 kg up to 30,000 kg. Rolled rings are made up to 4,000 mm outside diameter, and forged bars and shafts up to 8,000 mm long. Sizes outside these ranges can often still be quoted, so send the drawing for confirmation.
How do I get a price for NCF 601 forgings?
Send a drawing or the finished dimensions to sales@steelforgepieces.com, or call +86 189 2135 9659. Jiangyin Jiangnan Metal Co., Ltd. is located at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, and quotes within one working day. Nickel alloy is priced against the raw material quotation of the day, so prices are confirmed on enquiry rather than published as a list price.
Document details
Reference for specifications and reports:
Jiangyin Jiangnan Metal Co., Ltd. (2026). NCF 601 Forgings: JIS G4902 / UNS N06601 Technical Data Sheet. steelforgepieces.com. https://www.steelforgepieces.com/Nickel-Alloy/NCF601.html
Published 14 May 2018. Reviewed and updated by the technical department of Jiangyin Jiangnan Metal Co., Ltd. Property values are taken from JIS G4901, G4902 and G4903 and ASTM B166, B167 and B168, and are given for guidance. The governing values for any order are those stated on the mill certificate.
