Resistance wire

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Resistance wire is electrical wire used for its resistance. It is routinely used at high temperatures, so normally also has high melting point. Resistance wire is usually used for high-power resistors and heating elements, which produce heat used in electric heaters, electric ovens and toasters, and many other appliances.

[edit] Types

Nichrome, a non-magnetic alloy of nickel and chromium, is commonly used to make resistance wire because it has a high resistivity and resistance to oxidation at high temperatures. When used as a heating element, resistance wire is usually wound into coils.

Constantan is used where resistance is required to not change with temperature. Constantan is readily solderable, though soldered joints have limited temperature range.

Many elements and alloys have been used as resistance wire for special purposes. Copper is also included for comparison.

Material              Resistance
               (ohm-cmil/ft) (ohm-cm) 

Aluminum              15.94   2.650 e-6
Brass                 42.1    7.0 e-6
Carbon (amorphous)            3.8-4.1 e-6
Constantan            272.97  45.38 e-6
Copper                10.09   1.678 e-6
Iron                  57.81   9.61 e-6
Manganin              290     48.21 e-6
Molybdenum            32.12   5.34 e-6
Nichrome              675     112.2 e-6
Nichrome V            650     108.1 e-6
Nickel                41.69   6.93 e-6
Platinum              63.16   10.5 e-6
Stainless steel (304) 541     90 e-6
Steel (0.5% Carbon)   100     16.62 e-6
Tungsten              31.76   5.28 e-6
Zinc                  35.49   5.90 e-6