What Is 2.4856?

‘2.4856’ is the Werkstoff number for a nickel-based alloy, most commonly known as Inconel 625. The Werkstoff designation was developed by the German standards body DIN, with the term Werkstoff translating approximately to ‘material’.

The History of 2.4856

2.4856, also referred to as Inconel 625, was launched in 1964 following development by Special Metals Corporation. It achieves reasonably high strength through the addition of molybdenum and niobium to the nickel-chromium base, but nowhere as high as 2.4668 (Inconel 718).

Properties & Applications Of 2.4856

Due to the high level of chromium and molybdenum, 2.4856 is corrosion resistant in the most aggressive of environments. It is particularly resistant to pitting and crevice corrosion with a pitting resistance equivalent number (PREN) of over 45.

The high nickel content means that it is resistant to oxidation at elevated temperatures. This supports applications in jet engines, heat exchangers, furnace hardware and chemical plant equipment amongst others. 

With nearly 60% nickel composition, it is virtually immune from stress corrosion cracking.

In the annealed condition, this Inconel alloy is fully austenitic. This means that 2.4856 is also non-magnetic and also retains its toughness and mechanical properties at very low, cryogenic temperatures. 

The machining of nickel-based alloys, such as 2.4856, can be more challenging even though its strength is not particularly high. This is associated with their lower thermal conductivity relative to steels and stainless steels. Therefore, careful selection of tooling and machining parameters is required. 

It is typically supplied in hot worked and solution annealed condition, known as Grade 1. However, Alloy 625 Grade 2 requires a slightly different heat treatment to the more commonly selected specification, but it is usually possible for Langley Alloys to process our existing stock to meet the requirements of Grade 2. 

For aerospace applications, a more common specification is AMS 5666. It is sometimes possible for stock to be dual-certified to AMS 5666 and API 6A, thereby meeting the requirements of the aerospace, oil and gas and chemical processing industries.

Contact Langley Alloys Today

Langley Alloys stocks Alloy 625 (2.4856, UNS N06625, Inconel 625) as solid bars between 5/8” (15.875mm) and 10” (254mm) diameter. Our stock is certified to API 6A CRA and NACE MR0175 / ISO 15156-3.

For more information about 2.4856 or other nickel- based alloys, please don’t hesitate to contact us today. We would be happy to answer any questions that you may have regarding specifications and common applications.