Inconel 601 · UNS N06601 · W. Nr. 2.4851 · NiCr23Fe · Alloy 601
Inconel 601 (N06601): composition, properties, fittings and flanges
Inconel 601 (UNS N06601, W. Nr. 2.4851) is a nickel-chromium-iron alloy with 58-63 % nickel, 21-25 % chromium and a deliberate aluminium addition of 1.0-1.7 %. The aluminium forms a tightly adherent alumina-rich oxide scale that survives severe thermal cycling, so Inconel 601 is specified for radiant tubes, muffles, combustion…
- UNS
- N06601
- W. Nr.
- 2.4851
- Density
- 8.11 g/cm³ (0.293 lb/in³)
- Key strength
- 600 MPa / 87 ksi
Identification and standards
| Short form | Inconel 601 · UNS N06601 · W. Nr. 2.4851 · NiCr23Fe · Alloy 601 |
|---|---|
| Classification | High-chromium nickel-chromium-iron alloy with an aluminium addition |
| UNS | N06601 |
| Werkstoff number | 2.4851 |
| Material family | Inconel Alloys |
Chemical composition
| Element | Composition (wt %) | Why it is there |
|---|---|---|
| Nickel (Ni) | 58.0 - 63.0 | Matrix, resists nitriding and carburisation |
| Chromium (Cr) | 21.0 - 25.0 | Oxidation and hot corrosion resistance |
| Iron (Fe) | Balance | - |
| Aluminium (Al) | 1.00 - 1.70 | Forms the adherent alumina scale |
| Manganese (Mn) | 1.00 max | - |
| Silicon (Si) | 0.50 max | - |
| Copper (Cu) | 1.00 max | - |
| Carbon (C) | 0.10 max | - |
| Sulphur (S) | 0.015 max | - |
Note Single figures are maximum limits unless shown as a range. Always confirm against the heat-specific EN 10204 3.1 certificate supplied with your order.
Mechanical properties
| Tensile strength, min (annealed) | 600 MPa / 87 ksi |
|---|---|
| 0.2 % yield strength, min | 240 MPa / 35 ksi |
| Elongation in 2 in, min | 30 % |
| Typical hardness, annealed | 160 - 210 HB |
| 1000 h rupture strength at 900 °C, typical | Well above 300 series stainless steel |
| Maximum continuous service temperature in air | 1250 °C |
Warning Values depend on product form, section thickness and heat treatment. Larger sections generally achieve lower strength than thin product; always design against the applicable code allowable stress rather than these figures.
Physical properties
| Density | 8.11 g/cm³ (0.293 lb/in³) |
|---|---|
| Melting range | 1320 - 1370 °C (2410 - 2500 °F) |
| Modulus of elasticity | 206 GPa (29.9 x 10⁶ psi) |
| Thermal conductivity at 20 °C | 11.1 W/m·K |
| Mean coefficient of thermal expansion, 20-100 °C | 13.7 µm/m·°C |
| Specific heat capacity | 448 J/kg·K |
Specifications by product form
| Bar / rod | ASTM B166 / ASME SB-166 |
|---|---|
| Plate / sheet / strip | ASTM B168 / ASME SB-168 |
| Seamless pipe & tube | ASTM B167 / B163 |
| Forgings & flanges | ASTM B564 / ASME SB-564 (UNS N06601) |
| Butt weld fittings | ASTM B366 (WP601) |
| Welding consumables | ERNiCrFe-11 wire, ENiCrFe-11 electrode |
| UNS / EN / China | UNS N06601 · EN NiCr23Fe · W. Nr. 2.4851 |
Product forms available
Hangbo supplies this grade in the following forms. Sizes outside the listed range can often be produced to order.
- Seamless tube and pipe
- Forged rings, flanges and special shapes
- Fabricated radiant tubes, muffles, retorts and burner components
- Elbows, tees, reducers and caps to ASME B16.9
Typical applications
- Radiant tubes, muffles, retorts and trays in carburising and carbonitriding furnaces
- Ethylene cracking furnace and reformer hardware where metal dusting must be avoided
- Combustion chambers, flare tips and incinerator grates
- Catalyst support grids and thermowell protection tubes
- Pollution control scrubbers, regenerative thermal oxidisers and high-temperature ducting
- Gas turbine combustor liners and transition ducts
Welding, forming and machining
- Welding
- Good weldability using GTAW, GMAW and SMAW with ERNiCrFe-11 filler. No preheat; keep heat input low and interpass temperature below 150 °C to limit grain growth.
- Hot forming
- Hot work between 1175 °C and 950 °C, followed by annealing at 1000-1100 °C with rapid air cooling.
- Machining
- Similar to Inconel 600: positive rake carbide tooling, low speed, constant feed and rigid setups.
- Scaling behaviour
- Unlike Inconel 600, Inconel 601 develops an alumina inner oxide layer that survives thermal cycling. This layer is protective and should not be removed during service.
Buy Inconel 601 from Hangbo
Material is supplied with full heat-number traceability, solution annealing or ageing performed under calibrated furnace control, and an EN 10204 3.1 certificate covering chemical analysis, mechanical properties, heat treatment records and the agreed NDT scope. Positive material identification and third party inspection and test reports from SGS are available for critical service.