The copper-based low resistance heating alloy is widely used in low-voltage circuit breaker, thermal overload relay, and other low-voltage electrical product. It is one of the key materials of the low-voltage electrical products. The materials produced by our company have the characteristics of good resistance consistency and superior stability. We can supply all kinds of round wire, flat and sheet materials.
CuNi40(6J40)
Constantan is CuNi40,also named 6J40,it is a resistance alloy which is mainly made up of copper and nickel.
It has the low resistance temperature coefficient,wide working temperature scope(500 below),good machiningproperty,anti-corrosive and easy braze welding.
The alloy is non-magnetic. It is used for electrical regenerator’s variable resistor and the strain resistor,
potentiometers, heating wires, heating cables and mats. Ribbons are used for heating of bimetals. Another field of application is manufacturing of thermocouples because it develops a high electromotive force (EMF) in association with others metals.
Copper nickel alloy series:Constantan CuNi40 (6J40), CuNi1, CuNi2, CuNi6, CuNi8, CuNi10, CuNi14, CuNi19, CuNi23,CuNi30, CuNi34, CuNi44.
Main grades and properties
Type | Electrical resistivity (20degreeΩ mm²/m) |
temperature coefficient of resistance (10^6/degree) |
Dens ity g/mm² |
Max. temperature (°c) |
Melting point (°c) |
CuNi1 | 0.03 | <1000 | 8.9 | / | 1085 |
CuNi2 | 0.05 | <1200 | 8.9 | 200 | 1090 |
CuNi6 | 0.10 | <600 | 8.9 | 220 | 1095 |
CuNi8 | 0.12 | <570 | 8.9 | 250 | 1097 |
CuNi10 | 0.15 | <500 | 8.9 | 250 | 1100 |
CuNi14 | 0.20 | <380 | 8.9 | 300 | 1115 |
CuNi19 | 0.25 | <250 | 8.9 | 300 | 1135 |
CuNi23 | 0.30 | <160 | 8.9 | 300 | 1150 |
CuNi30 | 0.35 | <100 | 8.9 | 350 | 1170 |
CuNi34 | 0.40 | -0 | 8.9 | 350 | 1180 |
CuNi40 | 0.48 | ±40 | 8.9 | 400 | 1280 |
CuNi44 | 0.49 | <-6 | 8.9 | 400 | 1280 |