Kanthal (alloy)
Kanthal is the trademark for a family of iron-chromium-aluminium (FeCrAl) alloys used in a wide range of resistance and high-temperature applications. Kanthal FeCrAl alloys consist of mainly iron, chromium (20–30%) and aluminium (4–7.5 %). The first Kanthal FeCrAl alloy was developed by Hans von Kantzow in Hallstahammar, Sweden. The alloys are known for their ability to withstand high temperatures and having intermediate electric resistance. As such, it is frequently used in heating elements. The trademark Kanthal is owned by Sandvik Intellectual Property AB.
Characteristics
For heating, resistance wire must be stable in air when hot. Kanthal FeCrAl alloy forms a protective layer of aluminum oxide (alumina).[1] Aluminium oxide is an electrical insulator but has a relatively high thermal conductivity; special techniques may be required to make good electrical connections.
Ordinary Kanthal FeCrAl alloy has a melting point of 1,200 °C (2,190 °F). Special grades can be used as high as 1,425 °C (2,597 °F).[2]
See also
References
- ↑ Advanced Topic: Oxidation Resistant Materials
- ↑ US 7027722, Uemori, Susumu & Takashi Aitani, "Electric heater for a semiconductor processing apparatus", issued 2006-04-11