Constantan Definition
Resistance alloy with moderate resistivity and low temperature coefficent of resistance with a flat resistance/temperature curve over a wider range than the ”manganins”. CuNi44 Alloy wire also shows better corrosion resistance than the man ganins. Uses tend to be restricted to ac circuits. CuNi44/ CuNi40 /CuNi45 Constantan Copper Nickel Alloy Wire is also the negative element of the type J thermocouple with Iron being the positive; type J thermocouples are used in heat treating applications. Also, it is the negative element of the type T thermocouple with OFHC Copper the positive; type T thermocouples are used at cryogenic temperatures.
Chemical Content(%) CuNi44
Ni | Mn | Fe | Si | Cu | Other | ROHS Directive | |||
Cd | Pb | Hg | Cr | ||||||
44 | 1.50% | 0.5 | - | Bal | - | ND | ND | ND | ND |
Mechanical Properties CuNi44
Max Continuous Service Temp | 400 ºC |
Resistivity at 20ºC | 0.49 ± 5% ohm*mm2/m |
Density | 8.9 g/cm3 |
Temperature Coefficient of Resistance | < -6 ×10-6/ºC |
EMF VS Cu (0~100ºC) | -43 μV/ºC |
Melting Point | 1280 ºC |
Tensile Strength | Min 420 Mpa |
Elongation | Min 25% |
Micrographic Structure | Austenite |
Magnetic Property | Non. |