# NC20TA / Nimonic 80A / UNS N07080 / 2.4952 Forging Parts

Technical datasheet and manufacturing guide.

- Canonical page: https://www.steelforgepieces.com/Nickel-Alloy/NC20TA.html
- Published: 12 May 2022 · Last updated: 22 August 2026
- Reviewed by: Jiangyin Jiangnan Metal Co., Ltd. metallurgical engineering team

## Manufacturer

**Jiangyin Jiangnan Metal Co., Ltd.** — open-die forging factory
No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China
Telephone: +86-189-2135-9659
Email: sales@steelforgepieces.com
Website: https://www.steelforgepieces.com

| Item | Detail |
| --- | --- |
| Facility type | Open-die forging and seamless ring rolling |
| Grade supplied | NC20TA · Nimonic 80A · UNS N07080 · 2.4952 · NiCr20TiAl |
| Melting route | EAF + VOD + ESR (VIM + VAR on request) |
| Delivery condition | Solution treated 1080 °C/8 h AC + aged 700 °C/16 h AC |
| Max rolled ring OD | 2,500 mm |
| Max disc diameter | 1,800 mm |
| Max shaft length | 8,000 mm |
| Max single-piece weight | 8,000 kg |
| Bar diameter range | Ø25 – Ø500 mm |
| Certification | EN 10204 3.1 standard; 3.2 on request |
| Ultrasonic testing | EN 10228-3 · SEP 1921 · ASTM A388 |
| Typical lead time | 8–12 weeks (12–16 weeks for 3.2 or large pieces) |
| Quotation turnaround | Within 24 hours of receiving a drawing |

## What is NC20TA?

NC20TA is the French AFNOR designation for a wrought, age-hardenable nickel-chromium superalloy containing 18–21% chromium, 1.8–2.7% titanium and 1.0–1.8% aluminium with nickel as the balance. The same alloy carries the numbers UNS N07080, W.Nr. 2.4952 and 2.4631 (NiCr20TiAl), BS HR1 / NA20, JIS NCF80A and GB/T GH4080A, and it is sold commercially as Nimonic® 80A. Titanium and aluminium precipitate as the ordered gamma-prime phase Ni₃(Al,Ti) during ageing, which is what gives the alloy high tensile and creep-rupture strength together with good oxidation and sulphidation resistance at temperatures up to about 815 °C (1500 °F).

Jiangyin Jiangnan Metal Co., Ltd., an open-die forging factory at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, manufactures NC20TA in forged form to customer drawings: seamless rolled rings to 2,500 mm outside diameter, forged discs to 1,800 mm diameter, shafts to 8 m length, bars from Ø25 mm to Ø500 mm, and single pieces to 8,000 kg. Material is melted by EAF + VOD + ESR, supplied solution treated and aged, and certified to EN 10204 3.1 as standard.

### Key figures

| Figure | Value |
| --- | --- |
| UNS | N07080 |
| Werkstoff | 2.4952 |
| Chromium | 18–21% |
| Ti + Al (γ′) | 2.8–4.5% |
| Max service temperature | 815 °C |
| Density | 8.19 g/cm³ |
| Tensile strength | ≥ 1000 MPa |
| Max single piece | 8,000 kg |

### How the alloy works

Metallurgically the alloy is the age-hardenable version of Nimonic 75 (NC20T / UNS N06075). Both start from the same nickel-20% chromium base, which supplies oxidation and sulphidation resistance. NC20TA adds titanium and aluminium. During ageing these come out of solution as a fine, coherent, ordered FCC precipitate that shares a lattice with the matrix and obstructs dislocation movement. That single change roughly doubles room-temperature strength, from about 750 MPa to 1000–1240 MPa, and it keeps a large fraction of that strength at red heat.

Three consequences of the gamma-prime mechanism govern how NC20TA is bought, forged and used:

1. **Properties come from heat treatment, not from chemistry alone.** Material with a perfect analysis and the wrong ageing cycle will fail its mechanical test. The heat-treatment record on the certificate matters as much as the ladle analysis.
2. **The service ceiling is set by gamma-prime stability, at about 815 °C.** Above roughly 850 °C the precipitate coarsens and begins to dissolve back into the matrix, and strength collapses. The alloy still resists oxidation to around 1000 °C, but it is no longer a load-bearing material there.
3. **Combined titanium plus aluminium above about 3% makes the alloy sensitive to strain-age cracking during welding.** NC20TA sits at 2.8–4.5% Ti + Al, which places it squarely in the difficult band. Welding is done in the solution-treated condition, followed by re-solution and re-ageing, never on finished aged parts.

The grade has an unusually long service record. It was developed in Britain in the 1940s for early jet engine turbine blades, and although newer alloys long ago replaced it in the hottest sections of aero engines, it remains the standard material for heavy-duty exhaust valves, high-temperature bolting and industrial gas turbine rings and discs. These are applications where cost, forgeability and predictable behaviour matter more than the last 50 MPa of rupture strength.

### Trademark notice

Nimonic® and Inconel® are registered trademarks of the Special Metals Corporation group of companies. Nicrofer® is a registered trademark of VDM Metals. Pyromet® and CarTech® are registered trademarks of Carpenter Technology. Waspaloy® is a registered trademark of United Technologies. Each mark belongs to its respective owner. Material produced by Jiangyin Jiangnan Metal Co., Ltd. is correctly described as NC20TA / Alloy 80A / UNS N07080 / W.Nr. 2.4952 / NiCr20TiAl. It is the same generic chemistry, manufactured independently. We are not affiliated with, sponsored by, or endorsed by any trademark holder listed above.

## NC20TA forged product range

Table 1. NC20TA (UNS N07080) forged product range and size envelope at Jiangyin Jiangnan Metal Co., Ltd.

| Forged product | Size envelope | Route | Typical end use |
| --- | --- | --- | --- |
| Seamless rolled rings | 200 – 2,500 mm OD; wall ≥ 30 mm; height ≤ 600 mm | Radial-axial ring rolling | Turbine casing and seal rings, combustor rings, flange blanks |
| Forged discs and blanks | ≤ 1,800 mm Ø | Open-die / upset | Turbine and compressor disc blanks, valve seat blanks |
| Forged shafts and spindles | ≤ 8,000 mm length | Open-die / cogged | Hot-end shafts, valve spindles, exhaust-side stems |
| Forged round bars | Ø25 – Ø500 mm | Open-die / cogged | Bolting and stud stock to BS 4882 B80A, exhaust valve blanks |
| Forged flanges | ≤ 1,500 mm OD | Ring rolling / upset | High-temperature piping and pressure-vessel connections |
| Forged sleeves and bushings | Ø80 – Ø1,200 mm | Open-die + bore | Hot gas path bushings, burner and nozzle hardware |
| Forged tube sheets | ≤ 2,000 mm Ø | Open-die + machining | High-temperature heat exchangers, reformer hardware |
| Forged tubes and hollows | Ø100 – Ø1,000 mm OD | Pierce + expand | Nozzle bodies, sleeves, thick-wall hot-gas ducting |
| Forged blocks | ≤ 8,000 kg single piece | Open-die | Die-casting inserts and cores, hot-work tooling |
| Valve components | Per drawing | Open-die / near-net | Bodies, stems, seat rings, discs for high-temperature valves |
| Near-net-shape parts | Per customer drawing | Closed-die / near-net | Repeat-volume valve and turbine hardware |

Open-die forging is used for bars, shafts, blocks and large discs, wherever single-piece size matters more than repeatability. Seamless ring rolling produces rings from 200 mm to 2,500 mm outside diameter with circumferential grain flow. Near-net-shape and closed-die work is offered where quantity justifies tooling.

The alloy is expensive per kilogram, work-hardens under the tool, and cuts at roughly a quarter of the speed of austenitic stainless steel. Every kilogram removed in the machine shop instead of at the press is paid for three times: in raw material, in cycle time, and in tooling. Where quantity justifies the die, near-net forging usually pays for itself on the first order.

## What are the equivalent designations of NC20TA?

The names are equivalent; the specifications are not identical. ASTM B637, DIN 17742, EN 10269 and BS 3076 NA20 differ in their limits on iron, cobalt, carbon and phosphorus. Always name the governing standard and its revision on the order, not just the alloy name.

Table 2. NC20TA equivalent designations and cross-references

| Standard / body | Designation | Region and notes |
| --- | --- | --- |
| AFNOR (France) | NC20TA · NC 20 TA | French national designation, the subject of this page |
| UNS | N07080 | Unified Numbering System. The safest brand-free name for a purchase order |
| ASTM / ASME | ASTM B637 · ASME SB-637 | Precipitation-hardening nickel alloy bars, forgings and forging stock |
| Werkstoff / DIN | 2.4952 · 2.4631 | German material numbers. 2.4952 is the general grade; 2.4631 the closely controlled variant |
| DIN / EN designation | NiCr20TiAl | Per DIN 17742 (bar, forgings), DIN 17754, EN 10269 (fasteners), DIN EN 10302 (creep data) |
| ISO | NiCr20Ti2Al · ISO 6208 | International designation and plate/sheet specification |
| BS (bar) | BS 3076 NA20 · BS HR1 · BS2 HR1 | British Standard bar and billet |
| BS (other forms) | HR201 · HR401 · HR601 | Sheet and strip (HR201), tube (HR401), forgings and parts (HR601) |
| BS (fasteners) | BS 4882 grade B80A | Bolting for flanges and pressure-containing purposes |
| JIS (Japan) | NCF80A | Japanese Industrial Standard |
| GB/T (China) | GH4080A · GH80A | Chinese national superalloy designation |
| GOST / Russia | ChN77TYuR · EI437B | Nearest Russian equivalents; verify limits before substitution |
| Aerospace (AECMA / EN) | prEN 2188 · 2189 · 2190 · 2191 · 2396 · 2397 | European aerospace bar, sheet, forging and fastener specifications |
| Aerospace (UK / France) | MSRR 7011 · 7013 · 7095 · AIR 9165-37 | Rolls-Royce material specifications and French aerospace standard |
| Trade name (Special Metals) | Nimonic® 80A | Registered trademark. We do not sell under this brand |
| Trade name (VDM Metals) | Nicrofer® 7520 Ti · VDM® Alloy 80 A | Registered trademark of VDM Metals |
| Trade names (other) | Pyromet® 80A · CarTech® 80A · Nickelvac® 80A · Haynes 80A · Udimet® Ni-80A · VAT80A | Various producers' brands for the same chemistry |
| Common shop names | Alloy 80A · 80A · N80A · Ni80A | Informal but widely used on drawings and RFQs |

**Naming note: NC20TA versus NC20T.** One letter separates two different alloys. NC20T (Nimonic 75, UNS N06075, W.Nr. 2.4951) is the solid-solution grade with only 0.2–0.6% titanium and no deliberate aluminium; it cannot be age hardened and reaches roughly 750 MPa tensile. NC20TA (Nimonic 80A, UNS N07080, W.Nr. 2.4952) is the age-hardenable grade and reaches 1000–1240 MPa. Confusing them on a purchase order produces material that will not meet the mechanical minimums.

## What is the chemical composition of NC20TA?

The composition is deliberately lean. Chromium at 18–21% is set by oxidation and sulphidation resistance, titanium and aluminium are set by the volume fraction of gamma-prime wanted, and everything else is a controlled residual. Carbon is held low but not eliminated, because a small amount forms grain-boundary carbides that pin the boundaries and improve creep-rupture ductility, which is why European practice specifies a carbon band of 0.04–0.10% rather than a simple maximum.

Table 3. NC20TA / UNS N07080 chemical composition by governing standard (wt %)

| Element | ASTM B637 (N07080) | DIN 17742 / EN 10269 (2.4952) | BS 3076 NA20 | Metallurgical role |
| --- | --- | --- | --- | --- |
| Nickel (Ni) | Balance | ≥ 65.0 | ≥ 65.0 | FCC matrix; host for the gamma-prime precipitate |
| Chromium (Cr) | 18.0 – 21.0 | 18.0 – 21.0 | 18.0 – 21.0 | Forms the protective Cr₂O₃ scale; sulphidation and hot-corrosion resistance |
| Titanium (Ti) | 1.8 – 2.7 | 1.8 – 2.7 | 1.8 – 2.7 | Primary gamma-prime former; also ties up carbon and nitrogen as TiC/TiN |
| Aluminium (Al) | 0.5 – 1.8 | 1.0 – 1.8 | 1.0 – 1.8 | Gamma-prime former; improves oxide-scale adhesion |
| Carbon (C) | ≤ 0.10 | 0.04 – 0.10 | 0.04 – 0.10 | Grain-boundary carbides for creep-rupture ductility; excess embrittles |
| Iron (Fe) | ≤ 3.0 | ≤ 1.5 | ≤ 1.5 | Residual. High iron reduces oxidation resistance and gamma-prime stability |
| Cobalt (Co) | ≤ 2.0 | ≤ 1.0 | not specified | Residual from raw material. Restricted for nuclear service |
| Manganese (Mn) | ≤ 1.0 | ≤ 1.0 | ≤ 1.0 | Deoxidiser, sulfur getter |
| Silicon (Si) | ≤ 1.0 | ≤ 1.0 | ≤ 1.0 | Deoxidiser; assists scale adhesion in small amounts |
| Copper (Cu) | ≤ 0.2 | ≤ 0.2 | ≤ 0.2 | Residual; harmful to hot workability above the limit |
| Boron (B) | ≤ 0.008 | ≤ 0.008 | ≤ 0.008 | Grain-boundary strengthener; small additions markedly improve rupture life |
| Zirconium (Zr) | ≤ 0.15 | ≤ 0.15 | ≤ 0.15 | Grain-boundary strengthener, works with boron |
| Sulfur (S) | ≤ 0.015 | ≤ 0.015 | ≤ 0.015 | Impurity. Causes hot shortness during forging |
| Phosphorus (P) | ≤ 0.045 | ≤ 0.020 | ≤ 0.020 | Impurity; segregates to grain boundaries |
| Lead (Pb) | ≤ 0.0025 | ≤ 0.0020 | ≤ 0.0020 | Trace impurity; catastrophic for hot ductility |

**Melting practice.** Jiangyin Jiangnan Metal Co., Ltd. melts NC20TA by EAF + VOD followed by ESR (electroslag remelting). VOD removes carbon and dissolved gases; ESR refines the inclusion population and gives the directionally solidified ingot structure that forges cleanly and inspects well by ultrasound. For aerospace and rotating-component work we source VIM + VAR double-vacuum stock instead. Specify this at RFQ stage, because it changes both price and lead time substantially. Both the ladle analysis and the product analysis are reported on the EN 10204 certificate.

## What are the mechanical properties of NC20TA?

In the standard solution-treated and aged condition, NC20TA forgings show a room-temperature tensile strength of 1000–1240 MPa, a 0.2% proof strength of 620–850 MPa and elongation of 20–39%. EN 10269 sets the specified minimums for bar at Rp0.2 ≥ 600 MPa, Rm ≥ 1000 MPa and A ≥ 15%.

The table below is producer data for solution-treated and aged bar. Note the elongation column: ductility dips to a minimum of roughly 15% between 700 and 760 °C, the classic intermediate-temperature ductility trough of gamma-prime alloys, and then recovers as the precipitate softens. Parts that must be formed or straightened after ageing should not be worked through that window.

Table 4. NC20TA tensile properties versus temperature, solution treated 1080 °C/8 h AC + aged 700 °C/16 h AC

| Temperature | Tensile strength Rm | 0.2% proof Rp0.2 | Elongation A | Reduction of area |
| --- | --- | --- | --- | --- |
| 20 °C (68 °F) | 1000 MPa (145 ksi) | 621 MPa (90 ksi) | 39 % | not reported |
| 540 °C (1000 °F) | 876 MPa (127 ksi) | 531 MPa (77 ksi) | 37 % | not reported |
| 600 °C (1112 °F) | 834 MPa (121 ksi) | not reported | 27 % | 28 % |
| 650 °C (1200 °F) | 793 MPa (115 ksi) | 552 MPa (80 ksi) | 21 % | not reported |
| 700 °C (1292 °F) | 724 MPa (105 ksi) | not reported | 15 % | 19 % |
| 760 °C (1400 °F) | 600 MPa (87 ksi) | 503 MPa (73 ksi) | 17 % | not reported |
| 800 °C (1472 °F) | 496 MPa (72 ksi) | not reported | 21 % | 19 % |
| 870 °C (1600 °F) | 310 MPa (45 ksi) | 262 MPa (38 ksi) | 30 % | not reported |
| 900 °C (1652 °F) | 234 MPa (34 ksi) | not reported | 26 % | 35 % |

Table 5. NC20TA specified room-temperature minimums by condition

| Condition | Rp0.2 min | Rm | Elongation min | Hardness |
| --- | --- | --- | --- | --- |
| Solution treated (unaged) | ≈ 280 MPa | ≈ 750 MPa | 45 % | ≈ 170–200 HB |
| Solution treated + aged (standard) | 600 MPa | 1000 – 1250 MPa | 15 % | 250 – 350 HB |
| Solution + stabilise + aged (max creep) | 620 MPa | 1000 – 1240 MPa | 15 % | 280 – 350 HB |
| Typical achieved, forged bar | 620 – 850 MPa | 1000 – 1240 MPa | 20 – 39 % | 262 – 340 HB |

Minimums broadly follow EN 10269 and BS 3076 NA20 practice for bar. The unaged row is given because parts are sometimes machined in the solution-treated condition and aged afterwards. That is a legitimate route, but it must be stated on the order.

## Creep and stress-rupture properties

Above roughly 500 °C, NC20TA parts are sized by creep rather than by tensile strength. Table 6 gives the two numbers that matter: the stress that produces rupture, and the lower stress that produces just 1% plastic strain, each at 10,000 and 100,000 hours. For a component with a 100,000-hour design life, say an industrial gas turbine ring or a bolted joint in a boiler, the 1% creep at 100,000 h column is normally the governing allowable, not the rupture column.

The drop with temperature is severe: every 50 °C of extra metal temperature roughly halves the allowable stress. Between 600 °C and 700 °C the 100,000-hour rupture stress falls from 272 MPa to 75 MPa, a factor of 3.6 for a 100 °C rise. This is why an accurate metal temperature, rather than a gas temperature, is the single most valuable input to an NC20TA design.

Table 6. NC20TA (2.4952) creep and stress-rupture strength per DIN EN 10302

| Temperature | Rupture, 10,000 h | Rupture, 100,000 h | 1% creep, 10,000 h | 1% creep, 100,000 h |
| --- | --- | --- | --- | --- |
| 500 °C | 745 MPa | 587 MPa | 624 MPa | 530 MPa |
| 550 °C | 582 MPa | 416 MPa | 523 MPa | 390 MPa |
| 600 °C | 433 MPa | 272 MPa | 398 MPa | 257 MPa |
| 650 °C | 300 MPa | 157 MPa | 275 MPa | 149 MPa |
| 700 °C | 186 MPa | 75 MPa | 183 MPa | 72 MPa |
| 750 °C | 114 MPa | 37 MPa | 106 MPa | 33 MPa |
| 800 °C | 70 MPa | 20 MPa | 58 MPa | 16 MPa |

Heat treatment changes these numbers. Inserting the 850 °C / 24 h stabilising anneal between solution and ageing raises rupture life meaningfully at 650–750 °C, at some cost in room-temperature ductility. If your part is creep-limited rather than yield-limited, specify the stabilised route explicitly. It is not the default and it adds a furnace cycle to the price and the lead time.

## Physical properties of NC20TA

Table 7. NC20TA / UNS N07080 physical properties

| Property | Metric | Imperial | Note |
| --- | --- | --- | --- |
| Density | 8.19 g/cm³ | 0.296 lb/in³ | Use for forging weight calculation |
| Melting range | 1320 – 1365 °C | 2408 – 2489 °F | Solidus to liquidus |
| Max service temperature | ≈ 815 °C | ≈ 1500 °F | Load-bearing limit, set by gamma-prime stability |
| Max oxidation temperature | ≈ 1000 °C | ≈ 1832 °F | Scale resistance only; negligible strength at this point |
| Modulus of elasticity, 20 °C | 216 GPa | 31.3 × 10⁶ psi | Falls to 189 GPa at 500 °C, 161 GPa at 700 °C, 130 GPa at 800 °C |
| Shear modulus, 20 °C | 85 GPa | 12.3 × 10⁶ psi | Falls to 74 GPa at 500 °C, 67 GPa at 700 °C |
| Poisson's ratio | ≈ 0.27 | | Derived from E and G |
| Mean CTE, 20–100 °C | 12.7 µm/m·K | 7.06 × 10⁻⁶ /°F | Rises to 14.4 at 500 °C, 15.5 at 700 °C, 16.2 at 800 °C, 18.1 at 1000 °C |
| Thermal conductivity, 20 °C | 11.2 W/m·K | 77.7 BTU·in/ft²·h·°F | Rises to 19.4 at 500 °C, 24.5 at 800 °C. Low; heat concentrates at the tool tip |
| Specific heat, 20 °C | 448 J/kg·K | 0.107 BTU/lb·°F | Rises to 573 at 500 °C, 653 at 800 °C |
| Electrical resistivity, 20 °C | ≈ 1.24 µΩ·m | ≈ 124 µΩ·cm | Nearly flat with temperature, typical of Ni-Cr alloys |
| Relative permeability | 1.0006 | | Effectively non-magnetic at room temperature |
| Crystal structure | FCC γ matrix + ordered γ′ Ni₃(Al,Ti) | | No transformation on cooling; hardened by precipitation only |

## How is NC20TA heat treated?

The standard cycle for forged NC20TA bar, rings and discs is 1080 °C for 8 hours air cooled, followed by 700 °C for 16 hours air cooled. The first step takes titanium and aluminium into solution and sets grain size; the second precipitates the gamma-prime that carries the load. Air cooling rather than water quenching between the two steps is deliberate: it avoids quench cracking in heavy sections and does not meaningfully reduce the available gamma-prime.

Table 8. NC20TA heat-treatment routes by product form and objective

| Route / product form | Solution treatment | Stabilising anneal | Ageing | Objective |
| --- | --- | --- | --- | --- |
| Bar, forgings, rings: standard | 1080 °C / 8 h / AC | not used | 700 °C / 16 h / AC | General purpose; the default delivery condition |
| Bar, forgings: max creep-rupture life | 1080 °C / 8 h / AC | 850 °C / 24 h / AC | 700 °C / 16 h / AC | Coarsens boundary carbides; best rupture life and ductility |
| Alternative (VDM practice): max creep | 1050–1080 °C / 8 h / AC | 840–860 °C / 24 h / AC | 690–710 °C / 16 h / AC | Equivalent route with slightly wider process windows |
| Alternative: max tensile ductility | 1010–1050 °C / 8 h / AC | 840–860 °C / 24 h / AC | 690–710 °C / 16 h / AC | Finer grain, better ductility, some loss of rupture strength |
| Cold-rolled sheet | 1150 °C / 2–3 min / fluidised-bed quench, or 1040 °C / 20 min / AC | not used | 750 °C / 4 h / AC | Short cycle to limit grain growth in thin section |
| Welded assemblies | 1150 °C / 2–3 min / AC before welding | PWHT 925 °C / 1 h / AC | 750 °C / 4 h / AC | Avoids strain-age cracking; restores properties across the weld |
| Interstage anneal during cold work | 1040 °C / 20 min / RAC or WQ | not used | not used | Restores ductility between cold-forming passes |

Furnace uniformity is not a detail on this alloy. A ±15 °C swing during the 700 °C age changes the gamma-prime size distribution enough to move tensile strength by 50–80 MPa. Ageing furnaces used for NC20TA at Jiangyin Jiangnan Metal are surveyed to ±5 °C, and the recorded chart for your specific charge is issued with the certificate. If you are qualifying a new supplier for this grade, ask for the furnace survey report, not just the promise of one.

## How is NC20TA forged, machined and welded?

### Forging

Hot working is carried out between about 1050 and 1200 °C, finishing above 950 °C to avoid cracking. The alloy's flow stress at forging temperature is roughly three times that of carbon steel, so equipment sizing matters: a ring that a 3-tonne hammer handles easily in 42CrMo4 may need the 5- or 9-tonne hammer, or the press, in NC20TA. Forging reduction of at least 4:1 from the ingot is applied to break down the as-cast structure. For rings, the pierced blank is expanded on a radial-axial mill so that grain flow follows the circumference. That is why a rolled NC20TA ring outperforms the same ring machined from a plate or a solid billet under hoop stress and thermal cycling.

Sulfur, lead and low-melting-point contamination cause hot shortness, so furnaces are run clean and neutral to slightly reducing, and dies and tools used on leaded free-machining steels are kept away from nickel alloy work.

### Machining

NC20TA machines roughly like an annealed high-speed steel, and it is much harder work than austenitic stainless. Three properties combine against you: rapid work hardening, low thermal conductivity of about 11 W/m·K that concentrates heat in the cutting edge instead of carrying it away in the chip, and abrasive titanium and aluminium carbides. Practical rules are sharp positive-rake carbide tooling, turning speeds of roughly 10–25 m/min with coated carbide, heavy positive feeds of 0.15–0.30 mm/rev, rigid setups, generous flood coolant, and never dwelling in the cut. Fully aged material machines better than material that has only been stabilise-annealed.

### Welding

NC20TA has fair rather than good weldability, limited by strain-age cracking in the heat-affected zone. Weld in the solution-treated, unaged condition. Use GTAW (TIG), electron beam or laser with low heat input and minimal restraint. Filler is matching NC20TA where full strength is needed, or ERNiCr-3 (Inconel 82) / ERNiCrCoMo-1 (617 type) where a slightly softer, more crack-tolerant joint is acceptable. Keep the joint scrupulously clean; sulfur, lead, copper and even fingerprints cause cracking. Then re-solution treat and re-age the whole assembly. Welding a finished, aged NC20TA part and hoping to skip the reheat treatment is the single most common cause of field failures on this grade.

## Oxidation, sulphidation and corrosion resistance

Table 9. NC20TA descaled weight loss after continuous heating in air (mg/cm²)

| Temperature | 30 h | 100 h | 300 h | 1,000 h | Assessment |
| --- | --- | --- | --- | --- | --- |
| 750 °C | 1.8 | 1.9 | 2.5 | 5.3 | Excellent; protective scale fully established |
| 900 °C | 3.9 | 3.8 | 4.2 | 6.6 | Very good; scale still protective and adherent |
| 1000 °C | 7.1 | 7.4 | 10.5 | 16.0 | Acceptable for intermittent service only |
| 1100 °C | 8.0 | 12.9 | 18.8 | 21.2 | Scale spallation begins; short exposure only |

Table 10. NC20TA aqueous and gaseous corrosion behaviour

| Environment | Resistance | Comment |
| --- | --- | --- |
| Air / oxidising gas to 1000 °C | Excellent | Adherent Cr₂O₃ scale, aided by aluminium |
| Sulphur-bearing combustion gas | Excellent | The property that defines its use in heavy-fuel engine exhaust valves |
| Nitric, phosphoric, acetic acid | Good | Concentration and temperature dependent; verify for your duty |
| Sulfuric acid | Good in oxidising conditions | Reducing conditions attack the passive film; consider Hastelloy grades instead |
| Salt spray (NaCl), humidity | Excellent | Suitable for marine ambient exposure |
| Seawater immersion | Moderate | Not a seawater alloy. Use Monel 400 or a duplex stainless |
| Hydrochloric / reducing acids | Poor | Use Hastelloy C-276 or C-22 |
| Molten salts, vanadium-bearing ash | Limited | Hot corrosion accelerates sharply; consider a higher-Cr or coated grade |

## NC20TA compared with other nickel superalloys

Table 11. NC20TA against neighbouring nickel superalloys

| Property | Nimonic 75 (NC20T) | NC20TA (80A) | Nimonic 90 | Inconel X-750 | Waspaloy | Inconel 718 |
| --- | --- | --- | --- | --- | --- | --- |
| UNS | N06075 | N07080 | N07090 | N07750 | N07001 | N07718 |
| W.Nr. | 2.4951 | 2.4952 | 2.4632 | 2.4669 | 2.4654 | 2.4668 |
| Chromium % | 18–21 | 18–21 | 18–21 | 14–17 | 18–21 | 17–21 |
| Cobalt % | not specified | ≤ 2 | 15–21 | ≤ 1 | 12–15 | ≤ 1 |
| Ti + Al % | 0.2–0.6 | 2.8–4.5 | 3.5–5.4 | 3.0–4.0 | 4.2–5.3 | 1.3–1.9 (+ Nb) |
| Strengthening | Solid solution | γ′ Ni₃(Al,Ti) | γ′ | γ′ + Nb | γ′ + Mo | γ″ Ni₃Nb |
| Rm at 20 °C, MPa | ≈ 750 | 1000–1240 | 1100–1300 | 1100–1300 | 1200–1400 | 1240–1450 |
| Max load-bearing temp. | ≈ 900 °C (low stress) | 815 °C | 870 °C | 815 °C | 870 °C | 650 °C |
| Rupture, 100,000 h at 700 °C | ≈ 30 MPa | 75 MPa | ≈ 120 MPa | ≈ 90 MPa | ≈ 170 MPa | not rated |
| Forgeability | Good | Good | Moderate | Moderate | Difficult | Good |
| Weldability | Good | Fair | Poor | Fair | Poor | Good (sluggish γ″) |
| Relative cost | 0.8 × | 1.0 × baseline | 1.5 × | 1.3 × | 2.2 × | 1.4 × |
| Choose it when | Formability and oxidation resistance matter more than strength | You need proven hot strength to ~750 °C at the lowest cost | You need 50–100 °C more capability and can accept poor weldability | Springs, relaxation resistance, nuclear service | Highly stressed rotating parts above 750 °C | Best strength below 650 °C, and weldable |

The comparison that comes up most often is NC20TA against Inconel 718. Alloy 718 is stronger at room temperature, far easier to weld, and cheaper to buy in most markets, so it wins every time the service temperature stays below about 650 °C. Above that, its γ″ strengthening phase transforms to the stable δ phase and the strength advantage disappears rapidly. NC20TA is still working at 750 °C, where 718 is finished. We forge all of the grades in the table on the same equipment, so there is no commercial reason to steer you toward one over another.

## What is NC20TA used for?

Table 12. NC20TA applications by industry and forged product form

| Industry | Typical components | Why NC20TA |
| --- | --- | --- |
| Industrial and aero gas turbines | Casing and seal rings, disc blanks, combustor hardware, blade roots and fixings, nozzle rings | Retains strength to 815 °C with a proven, forgeable, weld-repairable alloy |
| Automotive and marine engines | Exhaust valves, valve seat inserts, valve spindles, turbocharger hardware | The defining application. Resistance to sulphur-bearing exhaust gas from heavy fuel oil |
| High-temperature bolting | Studs, nuts, bolts and fasteners to BS 4882 B80A, EN 10269 NiCr20TiAl | High proof strength plus low relaxation up to 700 °C in flanged steam and gas joints |
| Nuclear power | Boiler and steam generator tube supports, hanger hardware, spacer grids, springs | Creep resistance and dimensional stability over decades; low cobalt option available on request |
| Oil and gas, petrochemical | Forged valve bodies, stems, seat rings and discs; hot-service flanges; reformer hardware | Strength plus hot-gas corrosion resistance in high-temperature process service |
| Power generation (fossil) | Tube supports, hangers, high-temperature bolting, expansion hardware | Long-term creep stability at 600–700 °C metal temperature |
| Tooling and die casting | Die-casting inserts and cores, hot extrusion tooling, hot shear blades | Hot hardness and thermal fatigue resistance well beyond hot-work tool steel |
| Heat treatment and furnaces | Fixtures, baskets, retort hardware, roller and hearth components | Oxidation resistance combined with enough strength to carry a load hot |
| Aerospace fasteners | Bolts, studs and pins to AECMA prEN 2396 / 2397, MSRR 7011 / 7095 | Established qualification history and controlled trace-element chemistry |

## NC20TA production capability at Jiangyin Jiangnan Metal

Jiangyin Jiangnan Metal Co., Ltd. operates an open-die forging and ring-rolling plant in Jiangyin, Jiangsu Province, China, employing approximately 460 people including 9 senior engineers and 32 intermediate engineers. NC20TA is produced on the same equipment as the rest of our nickel superalloy range: Waspaloy, Rene 41, Inconel X-750 and the Nimonic grades, with segregated handling to prevent cross-contamination.

Table 13. Equipment qualified for NC20TA production

| Stage | Equipment | Capability for NC20TA |
| --- | --- | --- |
| Melting | EAF + VOD + ESR (audited partner mill) | Ti and Al controlled to target; ESR ingot for clean, forgeable stock. VIM + VAR sourced on request for rotating parts |
| Forging hammers | 1 t · 3 t · 5 t · 9 t forging hammers | Bars, sleeves, small rings, valve and bolting blanks |
| Forging press | 4,500–5,000 t hydraulic press | Shafts to 8 m, blocks and discs to 8,000 kg single piece |
| Ring rolling | 3 m and 6 m radial-axial ring mills | Seamless rolled rings 200–2,500 mm OD, wall ≥ 30 mm, circumferential grain flow |
| Heat treatment | Bogie-hearth and protective-atmosphere furnaces | Solution 1080 °C and age 700 °C with ±5 °C surveyed uniformity; recorded charts issued |
| Volumetric NDT | Ultrasonic flaw detection | EN 10228-3 · SEP 1921 · ASTM A388, acceptance class per order |
| Surface NDT | Dye penetrant; magnetic particle for ferrous work | PT per EN ISO 3452 on machined surfaces (NC20TA is non-magnetic, so MT does not apply) |
| Laboratory: chemistry | Optical emission spectrometer | Full elemental analysis, daily calibration against traceable standards |
| Laboratory: mechanical | Universal testing machine, impact tester, hardness testers | Tensile at room and elevated temperature, impact, hardness on coupons from the delivered heat |
| Laboratory: metallography | Metallographic microscope | Grain size to ASTM E112, inclusion rating, gamma-prime morphology, macroetch for grain flow |
| Special testing | Accredited subcontract laboratory | Stress-rupture testing, elevated-temperature tensile, corrosion testing added to the certificate on request |
| Machining | CNC turning, boring and milling | Rough or finish machining to drawing, recommended on this grade given its machining difficulty |

**Ordering matched sets from a single heat.** Where several NC20TA parts must behave identically in service (a disc and its mating ring, a set of turbine bolts, a bank of valve components), specify single heat and single heat-treatment charge on the purchase order. We will block the required tonnage from one ESR ingot, process it in one furnace charge, and cross-reference the pieces on a single certificate.

**Weight estimating.** NC20TA density is 8.19 g/cm³ (0.296 lb/in³). Convert the finished part volume to net weight, then add a machining allowance of roughly 30% for rings and discs and 25% for bars, blocks and sleeves to reach the rough forging weight. Those allowances are deliberately more generous than for steel, because NC20TA needs heavier stock removal to clear the forged surface and any residual scale.

## Standards, testing and certification

### What appears on the certificate

- Heat number, plus full ladle and product chemical analysis against the ordered specification
- Melting route (EAF + VOD + ESR, or VIM + VAR where specified)
- Mechanical test results (tensile, proof strength, elongation, reduction of area, hardness) on coupons from the delivered heat
- Complete heat-treatment record: solution, stabilise and age temperatures, hold times, atmosphere, cooling method, with the recorded furnace charts
- Ultrasonic examination report to EN 10228-3, SEP 1921 or ASTM A388, with the acceptance class
- Grain size to ASTM E112 and, on request, gamma-prime morphology from metallographic examination
- Dimensional inspection report
- Elevated-temperature tensile or stress-rupture test results, added on request; strongly recommended for turbine and pressure-retaining parts
- Cross-listed equivalent designations (NC20TA / UNS N07080 / 2.4952 / NiCr20TiAl / BS HR1)

EN 10204 3.1 is issued as standard. EN 10204 3.2 witnessed by Lloyd's Register, DNV, Bureau Veritas, ABS, SGS or TÜV is available on request and should be stated at RFQ stage, since it adds inspection hold points and lead time.

## How to specify an NC20TA forging order

1. **Name the grade.** NC20TA / UNS N07080 / 2.4952, not a trade name alone.
2. **Governing spec.** ASTM B637, DIN 17742, EN 10269 or BS 3076 NA20, plus the revision.
3. **Send the drawing.** Dimensions, tolerances, finish, grain-flow direction.
4. **State the condition.** Solution treated and aged, or solution treated only.
5. **State the objective.** Creep-limited or yield-limited, which decides the stabilising anneal.
6. **Melting route.** ESR is standard; VIM + VAR for rotating and aerospace parts.
7. **NDE and certification.** UT class, PT, grain size, EN 10204 3.1 or 3.2.
8. **Traceability.** Single heat and single heat-treatment charge where sets must match.

Table 14. Copy-ready NC20TA material callout for engineering drawings

| Line | Text |
| --- | --- |
| MATERIAL | NC20TA / UNS N07080 / W.Nr. 2.4952 / NiCr20TiAl to ASTM B637 (also satisfies DIN 17742, EN 10269, BS 3076 NA20) |
| CONDITION | Solution treated 1080 °C / 8 h / air cool + aged 700 °C / 16 h / air cool |
| OPTIONAL STABILISE | 850 °C / 24 h / air cool between solution and age. REQUIRED where creep-rupture life governs |
| PROPERTIES | Rp0.2 ≥ 600 MPa · Rm ≥ 1000 MPa · A ≥ 15%. Hardness 250–350 HB, tested on the delivered heat |
| FORM | Seamless rolled ring, circumferential grain flow. Machined-from-plate substitution NOT permitted |
| MELTING | EAF + VOD + ESR minimum (VIM + VAR where stated for rotating parts) |
| NDE | UT per EN 10228-3, quality class 3. PT per EN ISO 3452 on all machined surfaces |
| GRAIN SIZE | ASTM E112 grain size 4 or finer, reported |
| CERTIFICATION | EN 10204 3.1 mill certificate (3.2 with third-party witness where stated) |
| TRACEABILITY | All pieces of this assembly from a SINGLE HEAT and a SINGLE heat-treatment charge |
| MARKING | Heat number + grade + drawing number, vibro-etched on a non-functional surface (do not hard stamp) |

### Common ordering mistakes

- Writing a trade name only, with no UNS number or governing standard.
- Confusing NC20TA with NC20T (Nimonic 75). One letter, two different alloys.
- Leaving the heat-treatment condition unstated, so aged and unaged material both satisfy the order.
- Omitting the stabilising anneal on a creep-limited part, then failing a rupture test.
- Accepting a plate-machined ring where circumferential grain flow was assumed.
- Not specifying the melting route. ESR is adequate for most static hardware; rotating and aerospace parts usually require VIM + VAR. This is a large price and lead-time difference. Decide before the RFQ, not after the quotation.
- Ignoring cobalt for nuclear service. ASTM B637 permits up to 2% cobalt, which activates to Co-60 in reactor environments.
- Welding an aged part without re-solution and re-ageing.
- Quoting a net weight instead of a rough forging weight.
- Splitting a matched set across heats or furnace charges.

## Request a quotation

Send a drawing or a specification and we will respond within 24 hours with price, lead time and confirmation of the applicable standards. For creep-limited parts, state the metal temperature, the sustained stress and the required design life. Those three inputs determine whether the stabilising anneal is needed and therefore what the part costs.

**Jiangyin Jiangnan Metal Co., Ltd.** · Open-Die Forging Factory
No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China
Telephone: +86-189-2135-9659 · Email: sales@steelforgepieces.com

## Glossary

- **NC20TA** — AFNOR (French) designation for the age-hardenable nickel-chromium superalloy also known as Nimonic 80A, UNS N07080, W.Nr. 2.4952 and NiCr20TiAl. The letters encode the chemistry: Nickel, Chrome 20%, Titane, Aluminium.
- **UNS N07080** — Unified Numbering System designation for this chemistry. The generic, brand-free name to put on a purchase order.
- **Gamma prime (γ′)** — The ordered face-centred-cubic precipitate Ni₃(Al,Ti) that strengthens the alloy. It is coherent with the matrix, which is why it obstructs dislocations so effectively and why its stability sets the maximum service temperature.
- **Solution treatment** — Heating to 1080 °C to dissolve titanium and aluminium into the nickel matrix and set the grain size, followed by air cooling to hold them in supersaturated solution.
- **Ageing** — The controlled reheat, 700 °C for 16 hours, during which gamma-prime precipitates from the supersaturated matrix. This step, not the chemistry, creates the strength.
- **Stabilising anneal** — An optional intermediate soak at 850 °C for 24 hours that coarsens grain-boundary carbides, improving creep-rupture life and rupture ductility at 650–750 °C.
- **Strain-age cracking** — Cracking in the heat-affected zone of a weld, caused by gamma-prime precipitating during post-weld heating while residual welding stress is still locked in. The reason NC20TA is welded in the solution-treated condition.
- **Creep-rupture strength** — The stress that causes fracture after a stated time at a stated temperature, for example 75 MPa for 100,000 hours at 700 °C. Distinct from the 1% creep strength, which is the lower stress that produces 1% plastic strain in the same period and usually governs design.
- **Sulphidation** — Attack by sulphur-bearing combustion gas, which penetrates the protective oxide and forms low-melting nickel sulphides. NC20TA's resistance to it is the reason it dominates heavy-fuel engine exhaust valves.
- **ESR** — Electroslag remelting. A secondary melting process that refines inclusion content and produces a directionally solidified ingot suited to forging and to ultrasonic inspection.
- **VOD** — Vacuum oxygen decarburisation. A secondary refining step that lowers carbon and dissolved gases before remelting.
- **VIM + VAR** — Vacuum induction melting followed by vacuum arc remelting. The double-vacuum route used for rotating and aerospace hardware, giving the lowest gas and inclusion content.
- **Seamless rolled ring** — A ring produced by piercing a forged billet and expanding it on a radial-axial ring mill, giving continuous circumferential grain flow, structurally superior to a ring machined from plate or from solid.
- **EN 10204 3.1 / 3.2** — Inspection document types. 3.1 is a certificate issued by the manufacturer's own independent inspection department; 3.2 is countersigned by an independent third party nominated by the purchaser.
- **EN 10228-3** — European standard for ultrasonic testing of forgings, defining scanning coverage and acceptance quality classes.
- **BS 4882 B80A** — British Standard for bolting materials for flanges and pressure-containing purposes; grade B80A is this alloy.

## Frequently asked questions

**Are NC20TA, Nimonic 80A, UNS N07080, 2.4952 and NiCr20TiAl the same material?**
Yes. They all describe the same nickel-chromium-titanium-aluminium chemistry. NC20TA is the AFNOR (French) designation, Nimonic 80A is the trade name originally introduced by Special Metals, UNS N07080 is the American Unified Numbering System number used by ASTM B637, W.Nr. 2.4952 and 2.4631 are the German material numbers for NiCr20TiAl under DIN 17742 and EN 10269, and BS HR1, HR201, HR401, HR601 and BS 3076 NA20 are the British designations. JIS calls it NCF80A and the Chinese GB/T system calls it GH4080A. Composition limits differ slightly between the standards, mainly in iron, cobalt, carbon and phosphorus, so the governing specification should always be named on the order. Jiangyin Jiangnan Metal Co., Ltd. accepts orders under any of these callouts and cross-lists the equivalents on the EN 10204 certificate.

**What is the chemical composition of NC20TA?**
NC20TA (UNS N07080) contains 18.0–21.0% chromium, 1.8–2.7% titanium and 1.0–1.8% aluminium with nickel as the balance, normally a minimum of 65%. Limits on the remaining elements are approximately 0.10% maximum carbon, 1.0% maximum manganese, 1.0% maximum silicon, 3.0% maximum iron, 2.0% maximum cobalt, 0.2% maximum copper, 0.015% maximum sulfur, 0.008% maximum boron and 0.15% maximum zirconium. European practice under DIN 17742 and EN 10269 is tighter, holding iron to 1.5% maximum, cobalt to 1.0% maximum and carbon to a 0.04–0.10% band. Jiangyin Jiangnan Metal Co., Ltd. melts NC20TA by EAF plus VOD followed by ESR, and reports both the ladle and the product analysis on the EN 10204 3.1 or 3.2 certificate.

**What is the maximum service temperature of NC20TA?**
NC20TA retains useful tensile and creep-rupture strength up to about 815 °C (1500 °F), which is the figure normally quoted as its maximum service temperature. Oxidation resistance from the protective chromium oxide scale extends higher, to roughly 1000 °C for intermittent exposure, but by that point the gamma-prime strengthening phase has largely dissolved and load-bearing capacity is minimal. In practice, sustained design stress is set by creep: the stress for rupture in 100,000 hours falls from about 587 MPa at 500 °C to roughly 75 MPa at 700 °C and about 20 MPa at 800 °C. Above roughly 750 °C under load, a more heavily alloyed grade such as Nimonic 90, Waspaloy or Rene 41 is usually specified instead.

**What are the mechanical properties of NC20TA?**
In the standard solution-treated and aged condition (1080 °C for 8 hours air cooled, then 700 °C for 16 hours air cooled), NC20TA forgings typically show a room-temperature tensile strength of 1000–1240 MPa, a 0.2% proof strength of 620–850 MPa, elongation of 20–39% and hardness in the range of about 250–350 HB. Strength falls progressively with temperature: roughly 876 MPa tensile at 540 °C, 793 MPa at 650 °C, 724 MPa at 700 °C and 496 MPa at 800 °C. EN 10269 requires a minimum of 600 MPa proof strength, 1000 MPa tensile strength and 15% elongation for bar. Actual values for each delivered heat are reported on the material certificate issued by Jiangyin Jiangnan Metal Co., Ltd.

**How is NC20TA heat treated?**
The standard cycle for forged NC20TA bar and rings is solution treatment at 1080 °C for 8 hours followed by air cooling, then ageing at 700 °C for 16 hours followed by air cooling. Where maximum creep-rupture life is required, a stabilising anneal at 850 °C for 24 hours is inserted between the two steps, which coarsens grain-boundary carbides and improves rupture ductility. Sheet and thin sections use a shorter high-temperature solution treatment near 1040–1150 °C with ageing at 750 °C for 4 hours. Hot working is carried out between about 1050 and 1200 °C. Jiangyin Jiangnan Metal Co., Ltd. supplies the furnace charts and the recorded cycle with every NC20TA order.

**What is the density of NC20TA?**
The density of NC20TA (Nimonic 80A / UNS N07080) is approximately 8.19 g/cm³, equivalent to 0.296 lb/in³. Use this figure to convert a finished part volume into net weight when preparing a forging enquiry, then add roughly 20–35% for machining stock to reach the rough forging weight. The melting range is approximately 1320–1365 °C and the alloy is essentially non-magnetic, with a relative permeability of about 1.0006.

**What forged products are available in NC20TA?**
Jiangyin Jiangnan Metal Co., Ltd. produces NC20TA (UNS N07080) as seamless rolled rings from 200 mm to 2,500 mm outside diameter, forged rings, forged flanges to 1,500 mm outside diameter, forged round bars from 25 mm to 500 mm diameter, forged discs and blanks to 1,800 mm diameter, forged shafts and spindles to 8 m in length, forged sleeves and bushings, forged tube sheets to 2,000 mm diameter, forged tubes and hollows, forged valve bodies, stems and seat rings, gear blanks and near-net-shape parts to customer drawings. The maximum single-piece weight is 8,000 kg.

**Who manufactures NC20TA forged rings and flanges?**
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, that manufactures NC20TA (Nimonic 80A / UNS N07080 / W.Nr. 2.4952) forged rings, seamless rolled rings, flanges, shafts, discs, bars, sleeves and tube sheets to customer drawings. The plant operates 1, 3, 5 and 9 tonne forging hammers, a 4,500–5,000 tonne hydraulic press and 3 m and 6 m radial-axial ring rolling mills, and supplies EN 10204 3.1 certification as standard with 3.2 third-party witnessed inspection on request. Contact: +86-189-2135-9659, sales@steelforgepieces.com.

**What is the difference between NC20TA (Nimonic 80A) and Nimonic 75?**
Nimonic 75 (NC20T, UNS N06075, W.Nr. 2.4951, NiCr20Ti) is a solid-solution nickel-chromium alloy with about 0.2–0.6% titanium and no deliberate aluminium addition, so it cannot be precipitation hardened. NC20TA adds 1.8–2.7% titanium and 1.0–1.8% aluminium, which precipitate as gamma-prime Ni₃(Al,Ti) during ageing and roughly double the room-temperature strength, taking tensile strength from about 750 MPa to about 1000–1240 MPa. Nimonic 75 is chosen for oxidation-resistant sheet and low-stress components where formability and weldability matter more than strength; NC20TA is chosen where the part carries load at temperature, such as turbine discs, rings, bolting and exhaust valves.

**What is the difference between NC20TA and Inconel X-750?**
Both are gamma-prime age-hardenable nickel alloys, but Inconel X-750 (UNS N07750) contains 5–9% iron and about 0.7–1.2% niobium in addition to titanium and aluminium, whereas NC20TA is a leaner nickel-chromium-titanium-aluminium composition with iron held to 3% maximum and no niobium. X-750 offers slightly better relaxation resistance in springs and is widely used in nuclear service, while NC20TA has a longer track record in exhaust valves, turbine bolting and combustion hardware and generally forges and machines more predictably. The two are not interchangeable on a drawing: they are separate specifications with different mechanical minimums.

**Is NC20TA difficult to machine?**
NC20TA machines roughly like an annealed high-speed steel and is markedly harder to cut than austenitic stainless steel. It work-hardens rapidly, has low thermal conductivity of about 11 W/m·K so heat concentrates at the cutting edge, and produces abrasive wear from titanium and aluminium carbides. Practical rules are sharp positive-rake carbide tooling, turning speeds of roughly 10–25 m/min with coated carbide, heavy positive feeds of 0.15–0.30 mm/rev, rigid setups, generous flood coolant and never dwelling in the cut. Fully aged material actually machines better than material that has only been stabilise-annealed. Jiangyin Jiangnan Metal Co., Ltd. can supply NC20TA forgings rough machined or finish machined to drawing so this work does not fall on the customer.

**Can NC20TA be welded?**
NC20TA has fair rather than good weldability. Like other gamma-prime strengthened alloys with a combined titanium plus aluminium content above about 3%, it is susceptible to strain-age cracking in the heat-affected zone if welded in the aged condition. Best practice is to weld in the solution-treated condition using gas tungsten arc or electron beam processes with a matching or Inconel 82 / 617 type filler, keep heat input low, then re-solution treat and re-age the assembly. A post-weld heat treatment is necessary to restore full properties. Where a welded joint is unavoidable in a highly stressed part, the joint should be qualified on production-representative material.

**What is NC20TA used for?**
NC20TA is used for gas turbine components including blades, rotor and casing rings, discs and combustion hardware; high-temperature bolting, studs and fasteners to BS 4882 B80A; exhaust valves and valve seat inserts in internal combustion and heavy-fuel engines, where its resistance to sulphur-bearing combustion gas matters; tube supports and hanger hardware in nuclear steam generators; die-casting inserts and cores; and forged valve bodies, stems and seat rings for high-temperature service. Jiangyin Jiangnan Metal Co., Ltd. supplies forged blanks for all of these in the form of rolled rings, discs, bars and near-net-shape parts.

**What certification is supplied with NC20TA forgings?**
EN 10204 3.1 mill certification is supplied as standard, listing the heat number, full ladle and product chemical analysis, melting route, mechanical test results on coupons from the delivered heat, complete heat-treatment records with furnace charts, ultrasonic examination report and dimensional inspection. EN 10204 3.2 certification witnessed by an independent third party such as Lloyd's Register, DNV, Bureau Veritas, ABS, SGS or TÜV is available on request. Ultrasonic testing is performed to EN 10228-3, SEP 1921 or ASTM A388 as the order requires.

**What is the lead time and minimum order for NC20TA forgings?**
Standard NC20TA forgings in the solution-treated and aged condition typically ship 8 to 12 weeks from order confirmation. Large single pieces above 3 tonnes, orders requiring a stabilising anneal, and orders requiring EN 10204 3.2 third-party witnessed inspection extend to 12 to 16 weeks. Because NC20TA is melted to order rather than held in bulk stock, small quantities are usually consolidated against a scheduled melt. Single pieces are accepted for prototype and qualification work. Jiangyin Jiangnan Metal Co., Ltd. issues a quotation within 24 hours of receiving a drawing or specification at sales@steelforgepieces.com.

## Technical references

1. ASTM B637, Standard Specification for Precipitation-Hardening and Cold Worked Nickel Alloy Bars, Forgings, and Forging Stock for Moderate or High Temperature Service, ASTM International, West Conshohocken, PA.
2. ASME SB-637, the ASME Boiler and Pressure Vessel Code adoption of ASTM B637.
3. DIN 17742, Nickel wrought alloys with chromium: composition, Deutsches Institut für Normung.
4. DIN 17754, Nickel and nickel alloy rod and bar: technical delivery conditions, Deutsches Institut für Normung.
5. EN 10269, Steels and nickel alloys for fasteners with specified elevated and/or low temperature properties, CEN, Brussels.
6. DIN EN 10302, Creep resisting steels, nickel and cobalt alloys, CEN. Source of the creep and stress-rupture data in Table 6.
7. BS 3076, Nickel and nickel alloys. Bar, and BS 3072/3073 for sheet and strip, British Standards Institution.
8. BS 4882, Bolting for flanges and pressure containing purposes, grade B80A, British Standards Institution.
9. ISO 6208, Nickel and nickel alloy plate, sheet and strip, International Organization for Standardization.
10. JIS G 4901 / G 4902, corrosion-resisting and heat-resisting superalloy bar and plate, grade NCF80A, Japanese Industrial Standards.
11. GB/T 14992 and GB/T 14993, high-temperature alloy designation and wrought superalloy bar, grade GH4080A, Standardization Administration of China.
12. AFNOR NF A54 series, French national designations for nickel wrought alloys, including NC20TA.
13. AECMA prEN 2188, 2189, 2190, 2191, 2396 and 2397, European aerospace series specifications for Ni-Cr20-Ti-Al bar, sheet, forgings and fasteners.
14. EN 10204:2004, Metallic products. Types of inspection documents, CEN, Brussels.
15. EN 10228-3, Non-destructive testing of steel forgings, Part 3: Ultrasonic testing, CEN.
16. SEP 1921, Ultrasonic testing of steel forgings, Stahl-Eisen-Prüfblatt.
17. ASTM A388, Standard Practice for Ultrasonic Examination of Steel Forgings, ASTM International.
18. ASTM E112, Standard Test Methods for Determining Average Grain Size, ASTM International.
19. Special Metals Corporation, published technical data for NIMONIC® alloy 80A.
20. VDM Metals, published data sheet for VDM® Alloy 80 A / Nicrofer® 7520 Ti.
21. ASM Specialty Handbook: Heat-Resistant Materials, J.R. Davis (ed.), ASM International.
22. ASM Specialty Handbook: Nickel, Cobalt and Their Alloys, J.R. Davis (ed.), ASM International.
23. Sims, C.T., Stoloff, N.S. and Hagel, W.C., Superalloys II: High-Temperature Materials for Aerospace and Industrial Power, Wiley.
24. Reed, R.C., The Superalloys: Fundamentals and Applications, Cambridge University Press.

## Related grades and forged products

- Nimonic 75 — https://www.steelforgepieces.com/Nickel-Alloy/Nimonic-75.html
- Nimonic 80A — https://www.steelforgepieces.com/Nickel-Alloy/Nimonic-80A.html
- Nimonic 90 — https://www.steelforgepieces.com/Nickel-Alloy/Nimonic-90.html
- Waspaloy — https://www.steelforgepieces.com/Nickel-Alloy/Waspaloy.html
- Rene 41 — https://www.steelforgepieces.com/Nickel-Alloy/Rene-41.html
- Inconel X-750 — https://www.steelforgepieces.com/Nickel-Alloy/Inconel-X-750.html
- Inconel 718 — https://www.steelforgepieces.com/Nickel-Alloy/Inconel-718.html
- Forged and rolled rings — https://www.steelforgepieces.com/Forging-Rings/Forging-Ring.html
- Forged disks — https://www.steelforgepieces.com/Forged-Disks/Forged-Disk.html
- Forged bars — https://www.steelforgepieces.com/Forging-Bars/Forging-Bar.html
- Open die forgings — https://www.steelforgepieces.com/Forging-Parts/Open-Die-Forging-Parts.html

## Citation

This datasheet is maintained by the metallurgical engineering team at Jiangyin Jiangnan Metal Co., Ltd. and is free to quote, reference or link to.

> Jiangyin Jiangnan Metal Co., Ltd. (2026). NC20TA / Nimonic 80A / UNS N07080 / 2.4952 Forging Parts: Technical Datasheet and Manufacturing Guide. Jiangyin, Jiangsu, China. Retrieved from https://www.steelforgepieces.com/Nickel-Alloy/NC20TA.html. Last updated 22 August 2026.

© 2026 Jiangyin Jiangnan Metal Co., Ltd., Open Die Forging Factory, Jiangyin, Jiangsu, China.