Alloy 20 is a nickel, iron, chromium, molybdenum and copper alloy. Typically, nickel makes up approximately 30% of its composition, with iron being found in equal if not greater amounts. This provides corrosion resistance, and specifically resistance from chloride stress cracking. Alloy 20 is practically immune to chlorine and was designed to be used in sulfuric environments. It is commonly applied in acidic and/or corrosive environments, such as those that contain phosphoric and nitric acid. Alloy 20 has proven to be excellent under corrosive conditions and various forms of media. As a result, it is commonly found in processing applications—such as food or chemicals—along with pharmaceutical storage and processing.
Alloy 20 is pliable under both hot and cold working practices, however it does have some limitations in regards to temperature. Hot-working practices should stay between 2100—2250°F. Temperature control is essential in terms of work-hardening, forging and welding the metal due to potential risks to its stability. Overall, Alloy 20 is an excellent alternative to more expensive metals with similar applications.