Section 01
Alloy Overview & What Makes 2.4880 Unique
2.4880 — formally designated NiCo29Cr28Si under DIN 17744 — is a nickel-based superalloy alloyed with substantial amounts of cobalt, chromium, and silicon. Its defining feature is a four-element architecture in which every constituent plays a structural or protective role: nickel anchors the austenitic matrix; cobalt elevates the solidus temperature and adds solid-solution strength; chromium creates a self-healing Cr₂O₃ oxide scale; and silicon contributes both additional oxidation resistance and resistance to carburisation.
Unlike many nickel alloys that optimise for either high-temperature strength or aqueous corrosion resistance, 2.4880 NiCoCr28Si performs creditably across both domains. A design engineer facing a component that must survive cycling between 800 °C combustion gas and acidic condensate — as occurs in waste incineration or biomass power generation — has very few material options at competitive cost. 2.4880 is routinely one of them.
The alloy is typically supplied in the solution-annealed condition. It is not precipitation-hardenable; strength comes entirely from solid-solution hardening and from controlled grain refinement achieved through careful hot-working schedules — which is why the forging process itself is critical to final part performance. Jiangsu Liangyi supplies custom 2.4880 NiCo29Cr28Si open die forgings and seamless rolled rings from 30 kg to 30,000 kg per piece, manufactured to your drawings with EN 10204 3.1 mill test certificates.
Section 02
International Designations & Cross-Reference Equivalents
Procurement engineers frequently encounter the same alloy under different names depending on the standard system of the specification. The table below provides the complete international cross-reference for 2.4880 (NiCo29Cr28Si).
| Standard System | Designation | Notes |
|---|---|---|
| DIN 17744 (Germany) | 2.4880 / NiCo29Cr28Si | Primary European material number — reference this on purchase orders |
| EN 10095 / EN ISO 9723 | NiCo28Cr29Si | EN harmonised designation |
| Werkstoffnummer (W.Nr.) | W.Nr. 2.4880 | Six-digit German material identifier |
| ASTM / UNS (USA) | No direct UNS equivalent | Specify by chemistry per DIN 17744; reference ASTM B564/B564M for forging form |
| Historical trade designation | Nicrofer 2828 (VDM Metals) | Third-party trade name — always verify actual chemistry on EN 10204 MTC; not a Jiangsu Liangyi product name |
| Japanese JIS | No direct JIS equivalent | Specify by chemistry referencing JIS G4901 |
Section 03
Chemical Composition of 2.4880 per DIN 17744
The table below provides the full composition limits for 2.4880 (NiCo29Cr28Si) per DIN 17744. At Jiangsu Liangyi, our internal aim points are maintained tighter than the standard requires — particularly for silicon and carbon — to ensure consistent hot-workability and repeatable mechanical properties across all production heats.
| Element | Min wt% | Max wt% | Metallurgical Role |
|---|---|---|---|
| Ni | Balance | Balance | Austenitic matrix; general corrosion resistance; toughness and ductility |
| Co | 27 | 31 | Elevates solidus temperature; solid-solution strengthening; raises creep-resistance ceiling by ~30–50 °C |
| Cr | 26 | 30 | Forms self-healing Cr₂O₃ oxide scale; primary oxidation and hot-corrosion protection |
| Si | 2.0 | 3.0 | Forms SiO₂ sub-scale diffusion barrier; carburisation and sulphidation resistance |
| Fe | — | 2.0 | Residual element; strictly controlled to maintain hot-corrosion resistance |
| Mn | — | 0.5 | Deoxidant during melting; low content avoids MnS inclusion formation |
| C | — | 0.05 | Low carbon prevents sensitisation; maintains corrosion resistance in the HAZ after welding |
| S | — | 0.015 | Kept minimal to avoid hot shortness during forging |
| P | — | 0.020 | Kept minimal to avoid grain-boundary embrittlement during service |
Why cobalt at 29 wt% is the key performance driver
Cobalt is both the most expensive primary constituent and the most performance-critical. At 29 wt%, cobalt in solid solution suppresses γ′ dissolution at elevated temperature, effectively raising the practical creep-resistant temperature ceiling by approximately 30–50 °C compared to a cobalt-free alloy of otherwise identical chemistry — a difference that can be decisive for components cycling above 900 °C.
The silicon paradox in NiCoCr28Si
Silicon above about 1 wt% in nickel alloys normally raises concerns about hot-workability, because it promotes low-melting-point intermetallic phases at grain boundaries. In 2.4880, this risk is managed by the high cobalt content (which raises the effective solidus) and by strict control of the forging temperature window. The result is an alloy that captures silicon's protective benefits while remaining commercially forgeable to large cross-sections.
Section 04
Mechanical & Physical Properties of 2.4880 Forgings
Typical properties for solution-annealed 2.4880 (NiCo29Cr28Si) forgings per DIN EN ISO 9723, at room temperature:
Elevated-temperature tensile data
| Test Temp (°C) | Rm (MPa) | Rp0.2 (MPa) | A5 (%) |
|---|---|---|---|
| 20 °C | ≥680 | ≥280 | ≥30 |
| 400 °C | ~580 | ~210 | ~35 |
| 600 °C | ~520 | ~185 | ~38 |
| 800 °C | ~380 | ~155 | ~45 |
| 1000 °C | ~160 | ~100 | ~55 |
Section 05
High-Temperature Performance of 2.4880 NiCoCr28Si
The service ceiling for 2.4880 in oxidising atmospheres is approximately 1100 °C for intermittent service and 1050 °C for continuous operation. Above these limits the Cr₂O₃ scale transitions to volatile CrO₃ and oxidation rates accelerate sharply.
Oxidation resistance mechanism
At temperatures above 600 °C, chromium preferentially diffuses to the alloy surface and forms a slow-growing α-Cr₂O₃ scale. The high Cr content (26–30 wt%) ensures sufficient chromium is available to regenerate this scale after spallation — a self-healing behaviour critical to long-term service life. Silicon simultaneously enriches beneath the Cr₂O₃ layer as SiO₂, acting as a secondary barrier against continued oxidation.
Sulphidation resistance
In H₂S or SO₂-containing atmospheres at high temperature, the SiO₂ sub-scale significantly reduces sulfur ingress rates. This makes 2.4880 suitable for waste-to-energy applications where fuel sulfur content is uncontrolled, and for petrochemical equipment handling sour gas at elevated temperature.
Carburisation resistance
In CO or hydrocarbon-bearing atmospheres at high temperature, the silicon content of 2.4880 lowers carbon activity at the metal surface and suppresses carbon uptake, making it a common selection for ethylene cracker tube supports, carburising equipment, and heat treatment retort components.
Section 06
Corrosion Resistance of 2.4880 Alloy
At ambient temperature, 2.4880 behaves as a standard austenitic nickel alloy — good resistance to oxidising acids and atmospheric corrosion. However, without molybdenum, the alloy does not offer the exceptional pitting and crevice corrosion resistance of alloys such as 2.4858 (NiCr21Mo / UNS N08825) or 2.4643 (NiCr33Mo8).
The principal advantage of 2.4880 manifests at elevated temperature, where the SiO₂ sub-scale mechanism becomes decisive. Specify 2.4880 for combined high-temperature oxidation, hot-corrosion, carburisation and sulphidation resistance — not for ambient-temperature chloride resistance.
Section 07
Industrial Applications of 2.4880 NiCoCr28Si Forgings
The following industries regularly specify 2.4880 forged parts for high-temperature and mixed-corrosion service:
Variable fuel compositions — sulfur, chlorine, heavy metals — combined with furnace temperatures of 850–1050 °C make 2.4880 a preferred material for sulphidation and chlorination resistance in oxidising atmospheres.
Cycling service from cold standby to full load in biomass and coal-fired boilers requires good thermal fatigue resistance and a low CTE — both delivered by 2.4880 NiCo29Cr28Si.
Carburising and mildly sulphidising hydrocarbon atmospheres at 850–1050 °C are the primary driver for specifying 2.4880 over standard heat-resistant stainless steels.
The SiO₂ sub-scale barrier provides meaningful protection against sulphidation attack at temperatures above 600 °C.
Used in continuous or batch heat treatment furnaces running on natural gas, propane or endothermic atmospheres. Carburisation resistance is the primary selection driver.
Where waste must be processed at high temperature in constrained spaces, the combination of resistance to varied combustion chemistry and reliable mechanical integrity makes 2.4880 the specified choice.
Section 08
How 2.4880 NiCoCr28Si Compares to Other Alloys
Ratings below are engineering-judgment scores (1–10) based on application experience, not single-test measured values. All alloy names are referenced by material number and DIN/EN chemistry designation.
For applications below 400 °C in chloride environments, evaluate 2.4858 (NiCr21Mo) or 2.4643 (NiCr33Mo8). For very high mechanical strength at temperature, 2.4632 (NiCr20Co18Ti) may be preferred.
Section 09
Forging 2.4880 NiCoCr28Si: Process Considerations
2.4880 is hot-worked rather than cold-worked because the high cobalt and chromium content raises the recrystallisation temperature and increases flow stress at ambient temperature. Open die forging delivers a refined, homogeneous grain structure with through-section mechanical properties that cannot be replicated by casting.
Forging temperature window
The recommended hot-forging range is 1050–1200 °C. Working above 1200 °C risks incipient melting at silicon-rich grain boundary films. Working below 1050 °C leads to inadequate recrystallisation and residual strain, which can reduce creep resistance and increase susceptibility to stress-corrosion cracking in service.
Reduction ratio requirements
A minimum forging reduction ratio of 3:1 (cross-sectional area) is required to break down the as-cast dendritic structure. For critical components — turbine hardware, pressure-vessel flanges, valve bodies rated above Class 900 — Jiangsu Liangyi targets a minimum ratio of 4:1, with reduction distributed through the full cross-section.
Heat treatment: solution annealing
After forging, 2.4880 is solution-annealed at approximately 1100–1180 °C followed by water quenching or rapid air cooling, to dissolve carbides formed during forging, homogenise the microstructure, and relieve residual stresses.
Available product forms at Jiangsu Liangyi
Our 6,300-ton hydraulic press and 5-meter seamless ring-rolling mill allow us to produce these product forms to precise customer drawings. View full 2.4880 product specifications, size capabilities and lead times on our product page.
| Product Form | Maximum Dimension | Weight Range |
|---|---|---|
| Forged round bar | Ø 2,000 mm | 30 kg – 30,000 kg |
| Forged flat / rectangular bar | 1,200 × 800 mm cross-section | 30 kg – 20,000 kg |
| Seamless rolled ring | OD up to 6,000 mm | Up to 30,000 kg |
| Forged disc / flat disc | Ø 3,000 mm, T up to 500 mm | 30 kg – 25,000 kg |
| Custom near-net-shape | Per customer drawing | Per customer drawing |
Section 10
Sourcing & Certification Guidance for 2.4880 Forgings
Quality system certification
Jiangsu Liangyi Co., Limited holds ISO 9001:2015 quality management system certification. This is the certification we hold and can document. We do not claim other quality system certifications beyond ISO 9001:2015.
Mill test certificate (MTC)
Every 2.4880 forging order is supplied with an EN 10204 3.1 mill test certificate as standard, reporting actual heat chemistry, mechanical test results, and heat treatment records. An EN 10204 3.2 certificate — with a client-nominated third-party inspection body countersigning — is available upon request. Clients may appoint their preferred inspection agency, including SGS, Bureau Veritas (BV), TÜV, Lloyd's Register, DNV, Intertek, or CCIC. We coordinate the inspection; the resulting certificate is issued by that agency under its own authority, not ours.
Melting route
We produce 2.4880 forgings from VIM (Vacuum Induction Melting) material for standard applications and VIM+ESR (Electro-Slag Remelting) for components requiring maximum cleanliness and low inclusion content.
Non-destructive testing (NDT)
Standard NDT includes UT (Ultrasonic Testing) per ASTM A388 or EN 10228-3, and PT (Liquid Penetrant Testing) per EN ISO 3452. MT, RT and TOFD can be arranged on request.
Typical lead times
Standard 2.4880 forgings from stock-held VIM billets: 6–10 weeks from order confirmation. Large custom forgings requiring dedicated VIM+ESR melting: 14–20 weeks.
Section 11
Frequently Asked Questions About 2.4880 NiCoCr28Si Alloy
The material number is W.Nr. 2.4880. The full DIN 17744 designation is NiCo29Cr28Si. The equivalent EN ISO 9723 designation is NiCo28Cr29Si. There is no direct UNS number — specify by chemistry when ordering to ASTM standards.
For continuous service in dry oxidising atmospheres: approximately 1050 °C. For intermittent or cyclic service: up to 1100 °C. In sulphidising environments (H₂S, SO₂) the ceiling is lower. Contact our engineering team with your specific atmosphere and temperature profile for a precise recommendation.
Yes. 2.4880 is weldable by GTAW (TIG), GMAW (MIG) and SAW using matching or over-alloyed filler metal. Post-weld solution annealing at 1100–1150 °C is recommended for components in corrosive service, to dissolve HAZ carbide precipitation.
Per DIN 17744: Ni balance; Co 27–31 wt%; Cr 26–30 wt%; Si 2.0–3.0 wt%; Fe max 2.0 wt%; Mn max 0.5 wt%; C max 0.05 wt%; S max 0.015 wt%; P max 0.020 wt%.
Jiangsu Liangyi Co., Limited holds ISO 9001:2015 quality management system certification. Every forging order is supplied with an EN 10204 3.1 mill test certificate as standard. EN 10204 3.2 certificates with client-nominated third-party inspection bodies (SGS, BV, TÜV, DNV, Lloyd's Register, Intertek, CCIC) are available on request. We do not claim additional quality system certifications beyond ISO 9001:2015.
Like all high-nickel alloys, 2.4880 work-hardens rapidly and has low thermal conductivity. Recommended: sharp positive-rake carbide tooling; cutting speeds below 40 m/min for roughing; flood coolant throughout; avoid dwelling or rubbing the tool. Our near-net-shape forging service reduces the amount of final machining required.
Raw material cost for 2.4880 forgings is typically 3–5 times the cost of 310S per kilogram, driven primarily by the cobalt content. When total lifecycle cost is considered — including reduced replacement frequency and downtime costs — 2.4880 frequently delivers lower total cost of ownership over a 5–10 year horizon in high-temperature service environments.
Request a Quote for 2.4880 NiCoCr28Si Forgings
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