EN 10253-2 Type B buttweld pipe fittings in 2.4851 — Inconel 601 (NiCr23Al, N06601). A nickel-chromium-aluminium alloy designed specifically for high-temperature oxidation resistance. The aluminium addition forms a tightly adherent Al₂O₃ oxide scale that protects the alloy up to 1200°C. Distinguished from Inconel 600 (no Al) by superior scaling resistance. The primary selection criterion is oxidation resistance at very high temperatures — not aqueous corrosion resistance.
| Grade | W.Nr. | Al | Mo | Max Temp | Primary Use |
|---|---|---|---|---|---|
| Inconel 600 | 2.4816 | None | None | ~1100°C | Furnace, caustic, SCC resistance |
| Inconel 601 (this grade) | 2.4851 | 1.0–1.7% | None | ~1200°C | High-temp oxidation (Al₂O₃ scale) |
| Inconel 625 | 2.4856 | None | 8–10% | ~980°C | Corrosion: seawater, acids (Mo + Nb) |
| W.Nr. | 2.4851 |
| EN Name | NiCr23Al |
| ASTM UNS | N06601 |
| Trade Name | Inconel 601 |
Filler: ERNiCrFe-11 (matching 601 filler). No PWHT required. High-temperature applications typically require solution anneal for full oxidation resistance.
