2.4631 Forgings (NiCr20TiAl / Nimonic 80A / UNS N07080)
Open-die forged rings, flanges, shafts, discs and bars to DIN 17742 and ASTM B637
- 2.4631
- NiCr20TiAl
- Nimonic 80A
- Alloy 80A
- UNS N07080
- W.Nr. 2.4952
- GH4080A
- NCF 80A
- NA 20 / BS HR1
- NC 20 TA
Overview
2.4631 is the European material number for NiCr20TiAl, an age-hardenable nickel-chromium superalloy also known as Nimonic 80A, Alloy 80A and UNS N07080. It contains 18 to 21% chromium with 1.8 to 2.7% titanium and 1.0 to 1.8% aluminium, is strengthened by gamma-prime precipitation, and holds high tensile and creep-rupture strength up to 815 °C (1500 °F). A protective Cr2O3 scale gives oxidation resistance to about 1000 °C and good resistance to sulphur-bearing combustion gases.
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 2.4631 into seamless rolled rings, flanges, shafts, discs, sleeves, tube sheets and round bars to customer drawings, ultrasonically tested and certified to EN 10204 3.1 or 3.2. For a quotation, email sales@steelforgepieces.com or call +86 189 2135 9659.
Key facts at a glance
- Material number
- 2.4631 / 2.4952
- UNS
- N07080
- Alloy type
- Ni-Cr, age-hardenable
- Max service temp.
- 815 °C / 1500 °F
- Density
- 8.19 g/cm³
- Tensile (aged)
- 1250 MPa
- Yield Rp0.2 (aged)
- 780 MPa
- Elongation
- 30%
- Melting route
- EAF + VOD + ESR
- Standards
- DIN 17742, ASTM B637
Values are typical for the solution-treated and aged condition. Confirm against your purchase specification before design use.
What is 2.4631?
2.4631 (NiCr20TiAl) is a wrought, precipitation-hardenable nickel-chromium superalloy, sold commercially as Nimonic 80A.
Its composition is close to Nimonic 75, but additions of titanium and aluminium make it age-hardenable. Ageing precipitates a fine gamma-prime Ni3(Al,Ti) phase through the austenitic matrix. This roughly doubles room-temperature strength and holds creep-rupture strength at temperature.
The 18 to 21% chromium builds a tight, self-repairing Cr2O3 scale. It resists oxidation to around 1000 °C and also resists the sulphur compounds present in heavy-fuel-oil combustion gas, which is why the grade is standard for engine exhaust valves. Useful mechanical properties are retained to 815 °C, above the working range of stainless steels and Alloy 800.
The alloy work-hardens quickly and has a narrow hot-working window. Open-die forging with controlled reduction and finish temperature suits it better than heavy cold work. We use this route for 2.4631 rings, discs and shafts.
2.4631 equivalent grades and standards
2.4631 is listed under several names depending on the standard, the country and the mill. The table below gives the cross-reference for matching an older drawing to a current purchase order.
| System / region | Designation |
|---|---|
| Werkstoff-Nr. (Germany / EU) | 2.4631, also listed as 2.4952 |
| DIN chemical name | NiCr20TiAl |
| DIN / EN standards | DIN 17742, DIN 17754, DIN EN 10302, DIN EN 10090 |
| UNS (USA) | N07080 |
| ASTM / ASME | ASTM B637, ASME SB-637 |
| BS (United Kingdom) | BS 3076 NA 20, BS HR1, HR201, HR401, HR601 |
| AFNOR (France) | NC 20 TA |
| JIS (Japan) | NCF 80A |
| GB (China) | GH4080A |
| GOST (Russia) | ChN77TYuR, EI437B |
| Aerospace | MSRR 7011, MSRR 7095, AECMA prEN 2188 / 2191 / 2396 / 2397 |
| Trade names | Nimonic 80A, Alloy 80A, Nicrofer 7520 Ti, VDM Alloy 80 A, Haynes 80A, Pyromet 80A, Nickelvac 80A, CarTech 80A |
Cross-references are for guidance only. Equivalent grades are rarely identical in every element range or test requirement, so order to a named standard.
Chemical composition of 2.4631
Composition per DIN 17742 and ASTM B637, in weight percent. Nickel is the balance and single figures are maxima.
| Limit | C | Ni | Cr | Ti | Al | Fe | Mn | Si | Cu | Co | P | S | B |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Min | 0.04 | 65.0 | 18.0 | 1.8 | 1.0 | – | – | – | – | – | – | – | – |
| Max | 0.10 | bal. | 21.0 | 2.7 | 1.8 | 1.5 | 1.0 | 1.0 | 0.2 | 2.0 | 0.030 | 0.015 | 0.008 |
Some specifications, including Special Metals Nimonic 80A, allow Fe to 3.0% and add Zr max 0.15%. State the governing standard on your enquiry so the heat is selected correctly.
We melt 2.4631 by EAF plus VOD, followed by ESR remelting. The ESR step lowers sulphur and gas content and gives the directionally solidified ingot structure needed to meet tight ultrasonic acceptance on thick ring and disc sections.
Mechanical properties of 2.4631
Typical room-temperature properties after the standard solution and ageing treatment described below.
| Property | Metric | Imperial |
|---|---|---|
| Tensile strength, Rm | 1250 MPa | 181,000 psi |
| Yield strength, Rp0.2 | 780 MPa | 113,000 psi |
| Elongation at break, A | 30% | 30% |
| Maximum service temperature | 815 °C | 1500 °F |
| Oxidation and scaling resistance | to 1000 °C | to 1830 °F |
Typical values, not guaranteed minima. Properties vary with section size, forging reduction and test direction.
Physical properties of 2.4631
| Property | Value |
|---|---|
| Density at 20 °C | 8.19 g/cm³ (0.296 lb/in³) |
| Melting range | 1320 to 1370 °C (2410 to 2490 °F) |
| Coefficient of thermal expansion, 20 to 200 °C | 12.7 × 10-6 /K |
| Relative magnetic permeability at 20 °C | 1.001, non-magnetic |
| Structure | Austenitic FCC with gamma-prime Ni3(Al,Ti) |
Heat treatment of 2.4631
2.4631 develops its properties in two stages. A solution treatment dissolves the strengthening elements into the matrix, then an ageing hold precipitates them back out as fine gamma-prime.
- Solution treatment: 1080 °C, 8 hours, air cool. Dissolves gamma-prime and carbides into the austenitic matrix and sets grain size. Air cooling holds the elements in solution without the quench cracking risk of water.
- Precipitation ageing: 700 °C, 16 hours, air cool. Nucleates a fine, even dispersion of gamma-prime Ni3(Al,Ti). This step produces the tensile and yield values given in Table 3.
Where the design allows, weld before ageing. Welding in the fully aged condition raises the risk of strain-age cracking in the heat-affected zone. 2.4631 can be joined by TIG, MIG and MMA processes with matching or Ni-Cr filler.
2.4631 forged products we supply
We are an open-die forging factory, so most items below are made to the customer drawing rather than to a fixed catalogue size.
- 2.4631 seamless rolled rings
- 2.4631 forged rings
- 2.4631 forged flanges
- 2.4631 forged round bars
- 2.4631 forged shafts and spindles
- 2.4631 forged discs and disks
- 2.4631 forged sleeves and bushings
- 2.4631 forged tube sheets
- 2.4631 forged tubes and pipes
- 2.4631 forged valve bodies and seat rings
- 2.4631 forged nozzles and manifolds
- 2.4631 forged gears and gear blanks
- 2.4631 forged crankshafts and eccentric shafts
- 2.4631 custom open-die forgings to drawing
Applications of 2.4631 forgings
| Industry | Typical forged components |
|---|---|
| Gas turbines and aero engines | Turbine blades and blade roots, rotor and casing rings, discs, bolts and fasteners, ring seals |
| Automotive and large engines | Exhaust valves and valve seat rings for petrol, diesel and heavy-fuel-oil engines, turbocharger parts |
| Power generation and nuclear | Boiler tube supports, steam turbine fasteners, high-temperature hangers and studs |
| Oil, gas and petrochemical | Subsea and deepwater production components, wellhead and Christmas tree parts, valve bodies, ball and gate valve components |
| Pressure equipment | Heat exchanger tube sheets, shell flanges, nozzles, air receivers, columns and towers |
| Heavy and process machinery | Gearbox shafts, compressor rotors, forged rolls, die casting inserts and cores |
| Marine and shipbuilding | Exhaust gas system components, high-temperature fasteners, pump and valve internals |
Testing, inspection and certification
- Ultrasonic testing to EN 10228-3, SEP 1921 or ASTM A388
- Chemical analysis by spectrometer on ladle and product
- Mechanical testing for tensile, yield, elongation and reduction of area
- Hardness in Brinell or Rockwell as specified
- Impact testing at ambient or low temperature on request
- Grain size and microstructure examination
- Positive material identification (PMI)
- Dimensional inspection against drawing
- Certification to EN 10204 3.1 or 3.2
- Third-party inspection by TUV, SGS, BV, Lloyd's Register and others by agreement
How to get a 2.4631 quotation
- Send your drawing or size list. Email sales@steelforgepieces.com with dimensions in mm or inches, or attach a PDF or STEP drawing.
- Confirm the specification. Tell us the governing standard (DIN 17742, ASTM B637 or your own), the delivery condition, and whether you need 3.1 or 3.2 certification.
- State quantity and delivery. Piece count, target delivery date and destination port.
- Receive a firm quotation. Price, lead time and test scope, normally within one working day.
Supplier: Jiangyin Jiangnan Metal Co., Ltd.
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory in Jiangyin, Jiangsu Province, China. We produce forged rings, flanges, shafts, discs, sleeves and bars in carbon steel, alloy steel, tool steel, stainless steel and nickel-based superalloys, including 2.4631 (Nimonic 80A / UNS N07080). We manufacture to customer drawings and export worldwide.
Frequently asked questions about 2.4631
What is material 2.4631?
2.4631 is the European material number (Werkstoff-Nummer) for NiCr20TiAl, an age-hardenable nickel-chromium superalloy containing 18 to 21 percent chromium with titanium and aluminium additions. It is the same alloy sold internationally as Nimonic 80A, Alloy 80A and UNS N07080. Strengthened by gamma-prime precipitation, it retains high tensile and creep-rupture strength up to 815 C (1500 F) and forms a protective Cr2O3 layer that resists oxidation and sulphur-bearing combustion gases.
Is 2.4631 the same as Nimonic 80A?
Yes. 2.4631 and Nimonic 80A describe the same NiCr20TiAl alloy. Nimonic 80A is the Special Metals trade name, 2.4631 is the German and European material number, and UNS N07080 is the North American designation. Other equivalents include Alloy 80A, Nicrofer 7520 Ti, GH4080A (China), NCF80A (Japan), NA 20 and BS HR1 (UK) and NC 20 TA (France).
What is the difference between 2.4631 and 2.4952?
Both material numbers designate the age-hardenable NiCr20TiAl alloy known as Alloy 80A. 2.4952 is the number most often quoted in current EN and DIN documents, while 2.4631 appears in DIN 17742 and in many mill and purchase specifications. Datasheets commonly list the two together. State the exact material number and the governing standard on your purchase order so the mill certificate matches your specification.
What is the maximum service temperature of 2.4631?
2.4631 retains useful tensile and creep-rupture strength up to approximately 815 C (1500 F). Its protective chromium-oxide scale gives oxidation and scaling resistance to around 1000 C, but load-bearing design is normally limited to 815 C because gamma-prime strengthening declines above that point.
What is the standard heat treatment for 2.4631 forgings?
The standard cycle is solution treatment at 1080 C for 8 hours followed by air cooling, then precipitation ageing at 700 C for 16 hours followed by air cooling. This produces typical properties of about 1250 MPa tensile strength, 780 MPa yield strength and 30 percent elongation. Jiangyin Jiangnan Metal Co., Ltd. performs heat treatment in-house and supplies the furnace chart with each order.
Which forged shapes are available in 2.4631?
Jiangyin Jiangnan Metal Co., Ltd. produces 2.4631 as seamless rolled rings, forged rings, flanges, round bars, shafts, spindles, discs, disks, sleeves, bushings, tube sheets, forged tubes and pipes, valve bodies, valve seat rings, nozzles, gears and custom open-die forgings made to the customer drawing.
What testing and certificates are supplied with 2.4631 forgings?
Every 2.4631 forging is ultrasonically tested to EN 10228-3, SEP 1921 or ASTM A388 as agreed on the order. Chemical analysis, mechanical testing, hardness and dimensional inspection are standard. Certificates are issued to EN 10204 3.1, or EN 10204 3.2 with third-party inspection by bodies such as TUV, SGS, BV or Lloyd's Register.
Where can I buy 2.4631 (Nimonic 80A) forgings?
2.4631 forgings are supplied directly by Jiangyin Jiangnan Metal Co., Ltd., an open-die forging factory at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China. Send a drawing or size list to sales@steelforgepieces.com or call +86-189-2135-9659 for a quotation. The company exports worldwide and quotes against customer drawings, DIN 17742 or ASTM B637.
Related nickel alloy forgings
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Published 18 May 2016. Last reviewed 9 August 2026 by the technical team at Jiangyin Jiangnan Metal Co., Ltd.