Manganin

Manganin ( Cu84, Ni4, Mn12 ) is the brand name of a copper -manganese ( nickel ) alloy with a composition of 82-84 % copper, 12-15% manganese and 2-4 % nickel. It is a resistance alloy having an average resistivity (about 4.3 x 10-7 OMEGA.m ) and a low linear coefficient of temperature (low temperature dependence of the resistance ) ( α = 0.02 · 10-3 K-1). However, the resistance and temperature curve is not as flat as constantan, the corrosion resistance is also lower. Manganin 1903 was registered as a trademark of Isabelle Heusler.

Areas of application

Due to the small temperature dependence of manganin is often used as a measuring wire. In the low temperature physics manganin wires are used as the measurement lines in cryostats because of their low thermal conductivity. Since they have (with typical diameters: 100 Ω / m) a relatively high resistance is placed in the measurement of low resistances, the four-wire measurement.