UNS N07718 (Alloy 718) is often seen as the workhorse of the nickel-chromium alloy range, with many applications in Aerospace, General Engineering and the Oil & Gas industry. The grade is one of a type that is precipitation-hardenable, and which, with its addition of niobium, molybdenum, aluminium and titanium, provides a metal that is relatively high strength, and has excellent creep-stress rupture strength and good corrosion resistance. It is easy to weld and durable at high temperatures, although has a spread of operating temperatures of between -200°C and +550°C.
This article is one of a series that will explain each variant and pin-point differences:
This first article detailed the “Oil & Gas” API 6A CRA properties. The second article contrasted AMS5662 with API 6A CRA 718 properties. This third will address AMS5663 properties, and finally the fourth will discuss the general engineering ASTM B637 standard requirements.
I will compare and contrast API 6A 718 and AMS 5662 and AMS 5663 below. However, be aware that many end users of Alloy 718 may write their own specifications, usually extending certain requirements of the standards detailed below, and such specifications must always be checked to ensure material conforms with the requirements.
Our AMS5663 stock range is between 22 mm and 177 mm in diameter.
Alloy 718 To AMS5663
For bars, forgings, flash welded rings up to 10” (254 m) in least cross=sectional dimension and stock for any size for forging or flash welded ring. Typically used for parts requiring high resistance to creep and stress rupture up to 704o C and oxidation resistance up to 902o C. I will compare AMS5662 and AMS5663 together as parts are typically formed or machined from material meeting AMS5662, then precipitation heat treated to develop their required properties of AMS5663. AMS5662 material therefore comes with “capability” test results, where the test piece has been aged at the required times and temperatures, then tested to show what results would be achieved as AMS5663 with that ageing treatment.
The next paper in the series will consider ASTM B637 alongside AMS5663 properties.
Please contact Broder Metals Group Limited, either through the webform section of the website or by any of the other contact methods list on the website if you have any questions.