Resistance heating wire uses electrical resistance to generate heat from electric current. It is used in many electric devices that generate heat, such as heaters, stoves, hair dryers, radiant floor mats, toasters and electric water heaters.
As its name suggests, resistance heating wire consists of materials that have a high degree of electrical resistance, which is a property of a material that resists the flow of electricity. As the electricity flows through the resistant material, electrical energy is converted into heat energy.
The diameter and length of the wire have an impact on its electrical resistance. In general, thinner wires are more resistant than thicker ones, and the longer a wire becomes, the more resistant it is. For this reason, resistance heating wire is often coiled from one very long and thin wire.
Most commonly, resistance heating wire is made from nichrome, which is an alloy consisting of nickel and chromium. The exact proportions of nickel and chromium vary depending on the intended use. Iron is another element that may also be present in the alloy. Other materials used for resistance heating wire include cupronickel, an alloy of copper and nickel, and kanthal, an alloy of iron, chromium and aluminum.