Nickel alloy rod 825

corrosion-resistanthigh-temperatureannealed

Alloy 825, often referred to as Incoloy 825 (where Incoloy is a trademark of Special Metals Corp), is a nickel-iron-chromium alloy with additions of molybdenum, copper and titanium (NiCr21Mo), supplied in the hot worked and annealed condition. It achieves good mechanical properties from cryogenic to medium-high temperatures (5400C) and can be significantly strengthened through cold working. The high nickel content ensures resistance to stress corrosion cracking, combined with molybdenum and copper to strongly resist reducing environments such as sulphuric and phosphoric acids, chromium to resist oxidising environments such as nitric acid, titanium to inhibit intergranular corrosion, and overall resistance to pitting and crevice corrosion. The Incoloy family of alloys are all based upon a nickel-iron-chromium base composition, but with a varying number of additional alloying elements. They were originally developed and produced by the Special Metals Corporation group of companies, which includes the former Wiggins business in Hereford, UK that pioneered new alloys for use in Sir Frank Whittle’s original jet engine. They are designed for excellent corrosion resistance as well as strength at high temperatures; with specific alloys created to resist attack by particular chemicals. The Incoloy trademark, registered to Huntingdon Alloys Corporation (‘Special Metals Corporation’) has been in commercial use since the 1950’s, but many of the grades are now produced by other manufacturers. For instance, Sandvik manufacture a version of Incoloy 825 under their trademark Sanicro®41, whilst Bohler (Voest Alpine) manufacture L314.