Alloy family
Nickel-chromium superalloys. Materials that keep their strength above 1000 °C.
Inconel is the brand name for a family of nickel-chromium superalloys. One property makes it indispensable: it does not lose strength when hot.
Stainless steel begins to scale and weaken around 600 °C. Inconel keeps working above 1000 °C. The chromium oxide layer on its surface is self-renewing, so it survives repeated heating and cooling cycles.
Its second property is corrosion resistance. Grades such as 625 withstand high temperature, seawater and acid at the same time — a combination stainless steel cannot offer.
Inconel 600 is the oldest and most general-purpose member. Heat treatment furnaces, heat exchanger tubes, chemical process equipment. Weak in sulphur-bearing environments.
Inconel 601 adds aluminium for better oxidation resistance. Burner components, radiant tubes, flue gas ducts. The first grade to consider when 600 is not enough.
Inconel 617 adds cobalt and molybdenum and has among the highest creep strength in the family. Load-bearing parts above 1000 °C, gas turbine components, advanced power plants.
Inconel 625 is the most widely used grade. Niobium gives it high strength without heat treatment. Seawater, sour gas lines, exhaust bellows, chemical process. Covered by NACE MR0175, which makes it standard in oil and gas projects.
Inconel 718 reaches very high strength through precipitation hardening — over 1200 MPa after ageing, held up to 700 °C. Aerospace engine components, turbine discs, fasteners, wellhead equipment. This is the grade that takes over where titanium Grade 5 runs out of temperature.
Inconel X-750 for springs, clamps and parts needing elasticity at temperature.
Where it stops making sense. Inconel is expensive and heavy — 625 has a density of 8.44 g/cm³. It is difficult to machine and tool life suffers. Below 600 °C, in a moderately aggressive environment, 310S or 2507 may be a far more economical answer. We will say so at the quotation stage.
Sheet and plate, welded and seamless tube, bar and shaft, flanges, fittings, welding wire.
| Grade | W.Nr | UNS | Commonly requested standards |
|---|---|---|---|
| Inconel 600 | 2.4816 | N06600 | ASTM B168 (sheet), B166 (bar), B167 (tube) |
| Inconel 601 | 2.4851 | N06601 | ASTM B168, B166 |
| Inconel 617 | 2.4663 | N06617 | ASTM B168, B166, AMS 5887 |
| Inconel 625 | 2.4856 | N06625 | ASTM B443, B446, B444, NACE MR0175 |
| Inconel 718 | 2.4668 | N07718 | AMS 5596, AMS 5662/5663, ASTM B637 |
| Inconel X-750 | 2.4669 | N07750 | AMS 5542, AMS 5598 |
For 718, state the heat treatment condition as well: annealed, or solution treated and aged.
Send the grade, form, dimensions and quantity. Add the specification if one applies. We will come back with availability, price and lead time.
Quotation form