What NCF 718 is
NCF 718 is a nickel-chromium alloy that can be heat treated to give high strength, good corrosion resistance and ease of formability, and that can be welded with good resistance to strain-age cracking. Jiangyin Jiangnan Metal Co., Ltd. supplies NCF 718 forging material to the JIS standard.
The strength comes from gamma double prime, a niobium-bearing precipitate, with a smaller contribution from gamma prime formed by titanium and aluminium. Ageing is slow compared with other nickel alloys, so the material can be welded in the aged condition without strain-age cracking. That is why NCF 718 is chosen for fabricated high-temperature and sour-service equipment.
- Alloy family
- Age-hardenable nickel-chromium-iron superalloy, austenitic and non-magnetic
- Strengthening
- Precipitation hardening by Nb (gamma double prime) with Ti and Al
- Service range
- Cryogenic to about 700 °C (1300 °F) under load; oxidation resistant to about 980 °C
- Welding
- Can be welded in the aged condition with good resistance to post-weld strain-age cracking
- Standard governing the JIS name
- JIS G 4901 (bars) and JIS G 4902 (plate); pipe and tube in G 4903 and G 4904
- Supplier of the forgings on this page
- Jiangyin Jiangnan Metal Co., Ltd., Jiangyin City, Jiangsu Province, China
NCF 718 international equivalents
NCF 718, Inconel 718, Alloy 718, UNS N07718, W.Nr 2.4668 and GH4169 are the same alloy under different national designations. Jiangyin Jiangnan Metal Co., Ltd. forges all of them from the same melt route and certifies to the standard stated on the purchase order.
| Country or body | Standard | Designation |
|---|---|---|
| Japan | JIS G 4901 / G 4902 | NCF 718 |
| United States | UNS | N07718 |
| Germany and Europe | Werkstoff-Nr. | 2.4668 |
| Europe (EN name) | EN / ISO | NiCr19Fe19Nb5Mo3 |
| China | GB/T 14992 | GH4169 |
| South Korea | KS D 3704 | NCF 718 |
| France | NF A 35-573 | NC19FeNb |
| United Kingdom | BS | NA 51 |
| Trade names | None | Inconel 718, Alloy 718, Nicrofer 5219 |
| Product standards | Bar and forgings | ASTM B637 / ASME SB-637, AMS 5662, AMS 5663 |
| Sour service | NACE / ISO | NACE MR0175 / ISO 15156-3, API 6A CRA 718 |
Chemistry is common to all of these designations, but acceptance limits, heat-treatment windows and hardness caps differ between standards. Please state the standard and revision on your enquiry so the certificate matches your specification.
Chemical composition of NCF 718
The chemical composition of NCF 718 supplied by Jiangyin Jiangnan Metal Co., Ltd. is as follows, in weight percent.
| Ni | Fe | Cr | Cu | Mo | Nb | C | Mn |
|---|---|---|---|---|---|---|---|
| 50.00–55.00 | Remainder | 17.00–21.00 | 0.30 max | 2.80–3.30 | 4.75–5.50 | 0.08 max | 0.35 max |
| P | S | Si | Ti | Al | Co | B |
|---|---|---|---|---|---|---|
| 0.015 max | 0.015 max | 0.35 max | 0.65–1.15 | 0.20–0.80 | 1.00 max | 0.006 max |
Niobium may be reported as Nb+Ta. The heat analysis of every lot is reported on the mill certificate issued with the forgings.
Mechanical properties of NCF 718
Room-temperature mechanical properties depend on the delivery condition. NCF 718 is soft and ductile after solution treatment, and reaches full design strength only after the ageing cycle.
| Condition | Tensile Rm, min | Yield Rp0.2, min | Elongation, min | Reduction of area, min |
|---|---|---|---|---|
| Solution treated | 155 ksi / 1069 MPa | 95 ksi / 655 MPa | 30 % | Not specified |
| Solution treated and double agedtypical, to AMS 5663 / ASTM B637 | 185 ksi / 1276 MPa | 150 ksi / 1034 MPa | 12 % | 15 % |
Elongation is measured over 2 in or 4D gauge length. Aged-condition figures are the AMS 5663 and ASTM B637 minima, shown for comparison. Acceptance values for your order are those of the standard stated on the purchase order, and are reported on the certificate for the actual heat. Large section sizes and tangential ring specimens are tested per the applicable standard footnotes.
Physical properties of NCF 718
| Property | Value |
|---|---|
| Density | 8.19 g/cm³ (0.296 lb/in³) |
| Melting range | 1260 to 1336 °C (2300 to 2437 °F) |
| Maximum service temperature under load | about 700 °C (1300 °F) |
| Oxidation resistance | to about 980 °C (1800 °F) |
| Cryogenic capability | retains strength and toughness to −253 °C (−423 °F) |
| Magnetic response | non-magnetic in the annealed and aged conditions |
How Jiangyin Jiangnan Metal makes NCF 718 forgings
NCF 718 is melted by EAF plus VOD and then remelted by ESR. Double melting controls cleanliness and segregation. Niobium segregates readily in this alloy and can form Laves phase in heavy sections, so ESR is used as standard. Solution treatment and ageing are carried out together as one precipitation-hardening cycle.
- EAF meltingPrimary melt, alloy addition and initial refining
- VOD refiningVacuum oxygen decarburisation, degassing, low C, S and P
- ESR remeltingElectroslag remelted ingot for cleanliness and low segregation
- Ingot heatingHomogenising soak before the first forging heat
- Open-die forgingUpsetting, drawing and ring rolling to the ordered shape
- Solution treatmentNominally 940 to 1010 °C, air cooled
- Double ageingAbout 720 °C then 620 °C, furnace cooled between steps
- Rough machiningProof machined or machined to your finished drawing
- NDT and certificationUT to EN 10228-3, SEP 1921 or ASTM A388, then EN 10204 3.1 or 3.2
Soak times and cooling rates are set by the standard stated on the order. Where API 6A CRA or NACE MR0175 / ISO 15156-3 applies, the cycle is adjusted so the hardness cap and the strength minima are met together.
NCF 718 forged forms and size range
Jiangyin Jiangnan Metal Co., Ltd. produces NCF 718 forging parts, forged rings, rolled rings, forging flanges, round bars, forged disks, bushings, discs, forged tubes, sleeves, tube sheets, shafts and pipes to the requirement of the client. Single-piece weights run from about 5 kg to 20 tons.
| Form | Typical range | Usual end use |
|---|---|---|
| Seamless rolled rings | OD 200 to 4000 mm | Turbine casings, gearboxes, flanged joints, bearing races |
| Forged rings and retaining rings | OD to 4000 mm | Compressor and pump housings, connectors |
| Shafts, spindles, eccentric shafts | up to 12 m long | Pumps, turbines, compressors, mixers |
| Discs and disks | to 2500 mm dia. | Turbine and compressor discs, blind ends |
| Flanges | to 3000 mm dia. | Pressure vessels, piping, wellhead equipment |
| Round bars and blocks | dia. 60 to 1200 mm | Machined valve bodies, fasteners, forging stock |
| Sleeves and bushings | to 2000 mm dia. | Subsea equipment, wear parts, liners |
| Tube sheets | to 3500 mm dia. | Shell and tube heat exchangers |
| Forged pipes and tubes | bored or trepanned | Pressure piping, hollow shafts, cylinders |
| Gears, nozzles, crankshafts, valve parts | to drawing | Power transmission, process units, valve internals |
Ranges are indicative for the open-die and ring-rolling equipment in service. Send a drawing and we will confirm feasibility, forged weight and lead time for your exact geometry.
Related NCF 718 product pages
- Seamless rolled ringsRing-rolled, no weld seam
- Forging ringsAll grades, open-die
- Forged ringsMachined or as-forged
- Forging shaftsUp to 12 m
- Forged shaftsStepped and plain
- Forging flangesTo drawing or standard
- Forged flangesWeld neck, blind, slip-on
- Forging barsRound and block
- Forged barsPeeled or rough turned
- Forging partsCustom open-die parts
- Forged partsFull product index
- All nickel alloy forgingsCategory hub
Where NCF 718 forgings are used
Because of the mechanical properties of NCF 718 forging parts, there are many uses across industry.
| Industry | NCF 718 forged parts supplied |
|---|---|
| Pumps | Seamless rolled rings and forging shafts for chemical pumps and plunger pumps |
| Pressure equipment | Forged shafts, forging pipes, forged tubes, tube sheets and flanges for pressure vessels, air receivers and shell and tube heat exchangers |
| Process plant | Shafts, flanges, forged rings and pipes for columns, towers, tanks, silos, process modules and preheaters |
| Oil and gas, offshore | Forged bushings, sleeves, disks and discs for subsea and deepwater production systems, wellhead and Christmas tree equipment, industrial air compressors, power and nitrogen generators |
| Mills and mixers | Open-die forging parts, forging nozzles and forged crankshafts for cement mills, sugar mills, concrete mills and mixers |
| Valves | Forged valve stems, valve parts, valve seat rings, valve blocks and bodies for ball, check, globe, gate and plug valves and strainers |
| Power and rotating equipment | Forging rings, spindles, bars and gears for power transmission, turbines, gas compressors and gearboxes |
| Heavy industry | Forged wheels, manifolds and rolls for shipbuilding, heavy machinery, pulp and paper, pharmaceutical and biochemical plant |
Testing, NDT and certification
NCF 718 forged parts from Jiangyin Jiangnan Metal Co., Ltd. are ultrasonically tested as per standard: EN 10228-3, SEP 1921 or ASTM A388, whichever the order states. Certification is issued to EN 10204 3.1 as a works certificate, or EN 10204 3.2 with third-party witness.
| Test | Standard | Scope |
|---|---|---|
| Chemical analysis | Spectrometer, per heat | Standard |
| Tensile, yield, elongation, RA | ASTM E8 / ISO 6892-1 | Standard |
| Hardness | HB / HRC, including NACE cap | Standard |
| Ultrasonic testing | EN 10228-3, SEP 1921, ASTM A388 | Standard |
| Liquid penetrant | ASTM E165 / EN 10228-2 | On request |
| Impact and Charpy, including cryogenic | ASTM E23 / ISO 148-1 | On request |
| Grain size and microstructure | ASTM E112 | On request |
| Intergranular corrosion | ASTM G28 | On request |
| Certification | EN 10204 3.1 or 3.2 | Standard or third party |
How to order NCF 718 forgings
Please send the size or the drawing of the NCF 718 forged material that you need. Jiangyin Jiangnan Metal Co., Ltd. will quote the best price for your side.
- 1. Geometry
- Drawing (PDF, DWG or STEP) or rough forged dimensions with tolerances
- 2. Grade and standard
- NCF 718, or the equivalent designation and the standard revision you certify to
- 3. Condition
- Solution treated, or solution treated and aged; state any hardness cap
- 4. Machining
- As forged, proof machined, or finish machined to drawing
- 5. Testing
- UT class and acceptance level, plus any optional tests from Table 7
- 6. Quantity and delivery
- Piece count, required date and destination port or address
NCF 718 frequently asked questions
What is NCF 718?
NCF 718 is the Japanese Industrial Standard designation for the age-hardenable nickel-chromium superalloy known as Alloy 718, UNS N07718 and Werkstoff 2.4668. It contains 50 to 55 % nickel, 17 to 21 % chromium, 4.75 to 5.50 % niobium and 2.80 to 3.30 % molybdenum with iron as the remainder. It can be heat treated to high strength while keeping good corrosion resistance, formability and weldability, with good resistance to strain-age cracking.
Is NCF 718 the same as Inconel 718?
Chemically, yes. NCF 718 is the JIS name, Inconel 718 is the Special Metals trade name, UNS N07718 is the North American number, W.Nr 2.4668 is the European material number and GH4169 is the Chinese GB/T designation. Jiangyin Jiangnan Metal Co., Ltd. forges all of these from the same melt route and certifies to the standard your order states. Acceptance limits and hardness caps do vary between standards, so the standard and revision should always be stated on the order.
What forged shapes can be made in NCF 718?
Seamless rolled rings, forged rings, shafts, spindles, eccentric shafts, discs and disks, flanges, round bars, sleeves, bushings, tube sheets, forged pipes and tubes, gears, nozzles, crankshafts, valve bodies, valve stems and valve seat rings. Single-piece weights run from about 5 kg to 20 tons.
How is NCF 718 melted and heat treated?
Jiangyin Jiangnan Metal Co., Ltd. melts NCF 718 by EAF plus VOD, then remelts by ESR to control cleanliness and segregation. Forgings are solution treated and aged together in one precipitation-hardening cycle: solution treatment at nominally 940 to 1010 °C followed by double ageing near 720 °C and 620 °C. The exact cycle is set by the standard stated on the order.
What testing and certification comes with the forgings?
Ultrasonic testing to EN 10228-3, SEP 1921 or ASTM A388 as specified, with EN 10204 3.1 works certification or EN 10204 3.2 third-party certification. Chemical analysis, tensile testing, hardness, grain size, penetrant testing and hydrostatic testing can be added on request.
Can NCF 718 be used in sour service?
Alloy 718 is listed as a corrosion-resistant alloy under NACE MR0175 / ISO 15156-3 and API 6A CRA when the chemistry, heat treatment and maximum hardness limits of those documents are met. Please state the sour-service requirement on the enquiry so the ageing cycle is set to satisfy the hardness cap and the strength minima together.
What is the minimum order?
Open-die forging suits single pieces as well as batches, so prototype quantities can be quoted. Lead time depends on melt availability, forged weight and the heat-treatment schedule, and is confirmed with the quotation. Email sales@steelforgepieces.com or call +86 189 2135 9659.
How do I get a price for NCF 718 forgings?
Send the drawing or the rough forged dimensions, the grade and standard, the required condition and the quantity to sales@steelforgepieces.com, or call +86 189 2135 9659. Jiangyin Jiangnan Metal Co., Ltd. is at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China.
Datasheet reference
This datasheet is issued and maintained by the engineering department of Jiangyin Jiangnan Metal Co., Ltd., an open-die forging factory in Jiangyin City, Jiangsu Province, China. It may be quoted with attribution.
Jiangyin Jiangnan Metal Co., Ltd. "NCF 718 Forgings. JIS Alloy 718 (UNS N07718) Datasheet."
steelforgepieces.com, revision 2026-08-22.
https://www.steelforgepieces.com/Nickel-Alloy/NCF718.html
Contact: sales@steelforgepieces.com | +86 189 2135 9659
Revision , issued by the metallurgy and quality department. A plain-text version of this datasheet is available at NCF718.md.