NiCu30Fe is a solid-solution nickel–copper alloy (approximately 67% nickel, 30% copper) — the first of the corrosion-resistant nickel alloys, developed in 1905. This datasheet presents the material within the European (DIN / EN / Werkstoff-Nummer / VdTÜV) standard system.
It combines good mechanical properties with excellent resistance to a wide range of corrosive media. It is one of the few materials that resists hydrofluoric acid and fluorine, and is a benchmark material for seawater and marine service, where it resists flowing seawater, brackish water and brine. It also resists reducing acids such as sulphuric and hydrochloric under non-oxidising (de-aerated) conditions, alkalis, salts and most organic acids, and is highly resistant to chloride-ion stress-corrosion cracking. Being free of chromium, it is not suited to strongly oxidising environments.
The alloy is not age-hardenable; it is strengthened only by cold work. It retains strength and toughness from sub-zero temperatures to about 400 °C with no ductile-to-brittle transition, and is readily fabricated and welded. Typical applications include marine and offshore equipment (propeller shafts, seawater piping, pumps and valves), chemical and hydrocarbon processing, heat exchangers and feedwater heaters, crude-petroleum stills, fasteners and springs. It is listed in ISO 15156-3 / ISO 15156 for sour service.
Values per manufacturer ( / VDM) data, annealed condition.
| Property | Value | Unit |
|---|---|---|
| Density | 8.80 | g/cm³ |
| Melting range | 1300–1350 | °C |
| Young's modulus (20 °C) | 179 | GPa |
| Specific heat capacity (20 °C) | 427 | J/kg·K |
| Thermal conductivity (20 °C) | 21.8 | W/m·K |
| Electrical resistivity (20 °C) | 0.51 | µΩ·m |
| Coefficient of thermal expansion (20–100 °C) | 13.9 | µm/m·°C |
| Curie temperature | ~20–50 | °C |
| Magnetic response | Ferromagnetic near room temperature | — |
| Maximum service temperature | ~480; to ~540 in some service | °C |
Composition per DIN 17743 (W.Nr. 2.4360 / 2.4361, NiCu30Fe).
| Element | Symbol | Min % | Max % | Role in Alloy |
|---|---|---|---|---|
| Nickel (+ Co) | Ni | 63.0 | — | Base; corrosion resistance |
| Copper | Cu | 28.0 | 34.0 | Reducing-acid + seawater resistance |
| Iron | Fe | 1.0 | 2.5 | Controlled |
| Manganese | Mn | — | 2.0 | Deoxidiser |
| Silicon | Si | — | 0.5 | Deoxidiser |
| Carbon | C | — | 0.15 | Controlled |
| Sulphur | S | — | 0.01 | Residual impurity |
Nominal: Ni-31Cu-1.5Fe (). A solid-solution Ni-Cu alloy, hardenable only by cold work; outstanding seawater and HF resistance. (2.4360 and 2.4361 both designate this grade.)
Annealed (+A) condition, per DIN 17743 for W.Nr. 2.4360/2.4361.
| Property | Value | Unit |
|---|---|---|
| Tensile strength (Rm) | ≥440 | MPa |
| 0.2% proof strength (Rp0.2) | ≥160 | MPa |
| Elongation at fracture (A) | ≥25 | % |
| Brinell hardness | ~110–150 | HB |
Values per EN/DIN; confirm against the inspection certificate (EN 10204).
| Environment | Performance | Notes |
|---|---|---|
| Seawater / brackish water / brine | Outstanding | Benchmark marine material; resists flowing seawater |
| Hydrofluoric acid / fluorine | Outstanding | One of few materials resistant to HF and fluorine |
| Sulphuric / hydrochloric acid (reducing) | Very Good | Under non-oxidising (de-aerated) conditions |
| Alkalis | Excellent | Good resistance to caustic |
| Salts / most organic acids | Excellent | Broad resistance |
| Chloride stress-corrosion cracking | Outstanding | High nickel content |
| Sour service (H₂S) | Good | ISO 15156-3 / ISO 15156 |
| Stagnant seawater | Caution | May pit under stagnant conditions |
| Oxidising media (nitric acid, oxidising salts) | Poor | No chromium — avoid |
A solid-solution nickel–copper alloy; not age-hardenable. Heat treatment is for annealing / stress relief only; strengthening is by cold work.
Anneal Temperature: 700–900 °C, time depending on section and prior cold work, followed by appropriate cooling Purpose: softening and recrystallisation after cold work.
Stress relief of cold-worked material can be carried out at lower temperatures. The alloy has no ductile-to-brittle transition and retains toughness to cryogenic temperatures.
Readily welded by common processes and also brazed and soldered. The alloy is easily fabricated and retains good ductility in the as-welded condition.
| Welding Process | Applicability | Filler / Consumable |
|---|---|---|
| GTAW / TIG · GMAW / MIG | Excellent | EN ISO 18274 matching Ni-Cu filler (NiCu30Mn type) |
| SMAW / stick | Good | EN ISO 14172 matching Ni-Cu electrode |
Keep joints clean and free of contaminants. Welds should be made on clean, grease-free surfaces; the alloy's good weldability makes it well suited to fabricated marine and process equipment.
Machining Guidelines
| Parameter | Recommendation |
|---|---|
| Condition | Machines best cold-drawn or cold-drawn + stress-relieved |
| Work hardening | Work-hardens; rigid setup, sharp tooling, positive rake |
| Coolant | Flood coolant recommended |
Forming Processes
| Process | Notes |
|---|---|
| Hot forming | Standard hot-working practice for Ni-Cu alloys |
| Cold forming | Readily formed; work-hardens (strengthening by cold work) |
| Annealing | 700–900 °C after heavy cold work |
| Industry | Typical Components | Key Requirements |
|---|---|---|
| Marine / offshore | Propeller shafts, seawater piping, pumps, valves, fittings | Seawater + chloride-SCC resistance |
| Chemical processing | Reactors, heat exchangers, piping for reducing acids | Sulphuric/hydrochloric (reducing) + HF resistance |
| Oil and gas | Sour-service hardware, crude-petroleum stills | H₂S resistance |
| Hydrofluoric acid | HF production and handling equipment | One of few HF-resistant materials |
| Power / process | Feedwater heaters, heat exchangers | Corrosion resistance + thermal performance |
| Fasteners / springs | Bolts, fasteners, springs | Strength + corrosion resistance |
| Product Form | DIN Standard | VdTÜV | ISO / BS |
|---|---|---|---|
| Rod and bar | DIN 17752 | VdTÜV 263 | ISO 9723 · BS 3076 NA13 |
| Plate, sheet and strip | DIN 17750 | VdTÜV 263 | ISO 6208 · BS 3072 / 3073 NA13 |
| Seamless tube | DIN 17751 | VdTÜV 263 | ISO 6207 · BS 3074 NA13 |
| Forgings | DIN 17754 | — | ISO 9725 |
| Composition / designation | DIN 17743 · W.Nr. 2.4360 / 2.4361 · NiCu30Fe | — | AFNOR NU30 |
| Welding consumables | EN ISO 18274 matching Ni-Cu filler | — | — |
VdTÜV-Werkstoffblatt 263; listed in ISO 15156-3 / ISO 15156 for sour service. VDM trade name .
| EN Symbol | Ni % | Key Element | Type | Best Used For |
|---|---|---|---|---|
| NiCu30Fe | 63–70 | Cu 28–34 | Solid-solution Ni-Cu | Seawater, HF, reducing acids |
| NiCu30Al | 63–70 | Cu 27–33 | Age-hardened Ni-Cu (Al+Ti) | Higher strength; pumps/shafts |
| — | ≥99.0 | — | Commercially pure Ni | Caustic/alkali; conductivity |
| NiCr15Fe | ≥72 | Cr 14–17 | Ni-Cr-Fe | High-temperature oxidation |
| CuNi30Mn1Fe | 30 (Ni) | Cu balance | Copper-base Cu-Ni | Seawater (lower strength/cost) |




