The category of self-fusing alloys is distinctive because of fusing the coating after it has been sprayed by means of a relatively “cold” process. This happens at a temperature ranging from 1050 to 1200˚C. The fusing temperature is below the melting temperature of the base material.
Because of the high temperature this after-treatment is called fusing, as the sprayed on material is brought to a liquid state and then the sprayed product is cooled in a controlled manner to prevent tearing.
Fusing creates an homogenous coating, comparable to a welded-on layer, but with the difference that it does not mix with the base material.
Cobalt-based self-fusing alloys, also known under the brand name Stellite, are available in a wide range of hardnesses - from relatively soft easy to machine materials to extremely hard wear-resistant alloys. Alloyed with wolfram carbides cobalt-based self-fusing alloys acquire extreme wear resistance. This latter group can only be machined further by means of grinding. Cobalt-based materials are generally used in high-temperature applications because of their high resistance to high-temperature corrosion or wear problems.