Is Inconel rust proof?
Inconel 625 (UNS N06625) is a nickel-chromium-molybdenum alloy with excellent corrosion resistance in a variety of corrosive media, especially pitting and crevice corrosion. However, in corrosive environments, Inconel 625 is subject to corrosion like other metals. This study compared the corrosion performance of Inconel 625 when exposed to higher sulfate levels to real seawater. The results show that Inconel 625 has excellent resistance to seawater corrosion. However, as the temperature increases, the corrosion resistance of this metal decreases. It performs the same in seawater with elevated temperatures and high sulfate content. It can be concluded that sulfates promote perforation on Inconel 625 and act as an aggressive agent that accelerates corrosion.
| STANDARD | WERKSTOFF NR. | UNS |
| Inconel 600 | 2.4816 | N06600 |
| Inconel 601 | 2.4851 | N06601 |
| Inconel 617 | 2.4663 | N06617 |
| Inconel 625 | 2.4856 | N06625 |
| Inconel 690 | 2.4642 | N06690 |
| Inconel 718 | 2.4668 | N07718 |
| Inconel 725 | - | N07725 |
| Inconel X-750 | 2.4669 | N07750 |
Inconel-Chemical composition
| Inconel | Ni | Cr | Fe | Mo | Nb | Co | Mn | Cu | Al | Ti | Si | C | S | P | B |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 600 | 72 | 14.0-17.0 | 6.0-10.0 | 1 | 0.5 | 0.5 | 0.15 | 0.015 | |||||||
| 617 | 44.2-56.0 | 20.0-24.0 | 3 | 8.0-10.0 | 10.0-15.0 | 0.5 | 0.5 | 0.8-1.5 | 0.6 | 0.5 | 0.15 | 0.015 | 0.015 | 0.006 | |
| 625 | 58 | 20.0-23.0 | 5 | 8.0-10.0 | 3.15-4.15 | 1 | 0.5 | 0.4 | 0.4 | 0.5 | 0.1 | 0.015 | 0.015 | ||
| 690 | 59.5 | 30 | 9.2 | 0.35 | 0.01 | 0.02 | 0.35 | 0.019 | 0.003 | ||||||
| 718 | 50.0-55.0 | 17.0-21.0 | balance | 2.8-3.3 | 4.75-5.5 | 1 | 0.35 | 0.2-0.8 | 0.65-1.15 | 0.3 | 0.35 | 0.08 | 0.015 | 0.015 | 0.006 |
| X-750 | 70 | 14.0-17.0 | 5.0-9.0 | 0.7-1.2 | 1 | 1 | 0.5 | 0.4-1.0 | 2.25-2.75 | 0.5 | 0.08 | 0.01 |
