Summary
Both are precipitation-hardened alloys for large rotating parts. 706 was developed for very large land-based turbine forgings, and its scrap comes back as heavy forgings and turnings from that work.
706 carries roughly double the iron and no molybdenum, so it is worth less per tonne than 718 and must never be mixed into a 718 lot. See Inconel 718 scrap and Inconel 706 scrap.
Side by Side
| Inconel 718 | Inconel 706 | |
|---|---|---|
| Iron | About 18.5% | About 37.5% |
| Chromium | About 19% | About 16% |
| Niobium | About 5.1% | About 2.9% |
| Molybdenum | About 3% | None |
| Typical service | Aero engine discs, shafts, oilfield parts | Land gas turbine discs, wheels, spacers |
Composition Compared
Nominal compositions compared element by element. Change either grade to compare others.
On the XRF
Switch the grade to see how the fingerprint changes. See how XRF sorts nickel alloys.
FAQ
What is the main difference between Inconel 718 and Inconel 706?
Inconel 718 has about 18.5% iron, 19% chromium, 5% niobium and 3% molybdenum. Inconel 706 has about 37.5% iron, 16% chromium, 2.9% niobium and no molybdenum.
Can Inconel 718 and Inconel 706 scrap be mixed?
No. Keep them separate. A melter buying either one needs its chemistry to stay within the grade’s limits, and mixing can mean a re-sort or a different valuation.