AMS5666 is an aerospace material specification covering an alloy similar in composition to Inconel 625. It spans several product forms including forgings, extrusions and rings; our focus is on stocking and distributing solid bar.
AMS stands for Aerospace Material Specifications. AMS5666 is one of thousands of documents covering materials and products for aerospace use. The AMS standards are issued and maintained by SAE (formerly the Society of Automotive Engineers), a USA-based body focused on global transport industries such as aerospace, automotive and commercial vehicles.
The composition defined by AMS5666 differs only slightly from other product standards such as API 6A, ASTM B446 and NACE MR0175 / ISO 15156-3. A single product can therefore meet all of these specifications at once, whether for aerospace, oil and gas or chemical processing. Our stock meets AMS5666 and can be supplied for aerospace use, even though many of our customers work in other applications.
About Inconel 625
Inconel 625 is a nickel-based alloy, also known as UNS N06625, Alloy 625 or DIN 2.4856. It was launched in 1964 following development by Special Metals Corporation, and found early use in power station components thanks to its resistance to high-temperature oxidation.
Alloy 625 achieves reasonably high strength through additions of molybdenum and niobium to the nickel-chromium base, though nowhere near as high as Inconel 718. Its high chromium and molybdenum content make it highly corrosion resistant in the most aggressive environments.
It is one of the more expensive alloys we stock, given its high nickel content (>58%), but it performs strongly at temperatures above 800degC. Special Metals quote service temperatures from cryogenic up to 980degC for Inconel 625, although mechanical properties start to drop off more significantly from 650-700degC.
The high nickel content forms a protective oxide layer at elevated temperatures, preventing further oxidation. This makes Alloy 625 an obvious candidate for aerospace, where engine components on the exhaust side - nozzles, seals, heat shields, valves and fasteners - are commonly machined from it.
Our current stock runs from 1/2" (12.7mm) to 10" (254mm) diameter solid bar. We also offer in-house inspection, testing and CNC machining, including deep hole boring, to simplify your supply chain.