Question No.  15762 :
What is constantan and what are its properties and uses?

Constantan is an alloy of 45 percent nickel and 55 percent copper, used chiefly in electrical instruments because of its constant resistance under variations of temperature. Another common heat-resistant alloy is nichrome (with 80% nickel and 20% chromium). Constantan has a comparatively high resistance and low temperature coefficient of resistance. It is used extensively in electrical windings. It is used for the repair or manufacture of mass spectrometers filaments and heaters. Wires such as constantan and iron can be used to manufacture thermocouples, with a comparatively large e.m.f. Of all modern strain gauge alloys, constantan is the oldest, and still the most widely used. This situation reflects the fact that constantan has the best overall combination of properties needed for many strain gauge applications. This alloy has, for example, an adequately high strain sensitivity, or gage factor, which is relatively insensitive to strain level and temperature. Its resistivity is high enough to achieve suitable resistance values in even very small grids, and its temperature coefficient of resistance is not excessive. In addition, constantan is characterised by good fatigue life and relatively high elongation capability. Question Asked By:

Name: jevan dhillon

Age Group: 13 to 20

Occupation Type: Student

Education Level: A Level's