Cobalt based alloys (or cobalt based superalloys) are metals whose major mass fraction is cobalt.
The base combination of most cobalt alloys is cobalt-chromium, with chromium acting as a strengthening alloy. Adding tungsten and/or molybdenum can affect strengthening even more. Another common element that is found in many cobalt-based alloys is nickel. Nickel is even more heat resistant than cobalt and is added to widen components’ range of temperature resistance. Generally, cobalt-based alloys display favourable mechanical properties. They are corrosion, wear and heat resistant and are therefore used for components in challenging areas applications, such as hot gas turbines. Cobalt also displays great resistance against sulfides, preventing any sulfidation of the material.