What is "constantan"

constantan \constantan\ n. a copper-nickel alloy composed of approximately 55 per cent copper and 45 per cent nickel, with high electrical resistance and a low temperature coefficient; it is used as resistance wire and in thermocouples.

Note: It has a resistance factor [rho] of 44.1 x 10^ -6 ohm-cm at 0[deg] C, in comparison to the value 1.71 x 10^ -6 ohm-cm for pure copper and 7.8 x 10^ -6 ohm-cm for pure nickel. It is similar to the alloy Eureka, which has a [rho] = 47 x 10^ -6 ohm-cm.
--Handbook of Ch. 61.

n. An alloy of copper and nickel whose resistivity is constant over a wide temperature range

n. a copper-nickel alloy with high electrical resistance and a low temperature coefficient; used as resistance wire [syn: Eureka]

Constantan, also known as Eureka, Advance and Ferry, is a copper– nickel alloy usually consisting of 55% copper and 45% nickel. Its main feature is its resistivity, which is constant over a wide range of temperatures. Other alloys with similarly low temperature coefficients are known, such as manganin (CuMnNi).