Project Description


6J12 is a copper-manganese-nickel alloy (CuMnNi alloy) for use at room temperature.

Similar Grade

6J12Mangnin 47


GB/T 6145-1999

Product Forms

Wire, Ribbon, Strip, Tape

Chemical Composition, %


Physical Property

Max Continuous Service Temp5-45℃Elongation6~15%
Resisivity at 20℃0.47ohm mm2/mEMF vs Cu, μV/℃ (0~100℃)1(max)
Density8.4 g/cm3Tensile Strength of soft condition343-539 N/mm2
Thermal Conductivity40 KJ/m·h·℃Tensile Strength of hard condition>637 N/mm2
TCR at 20℃-3~+20×10-6/ºCHardness of soft condition100-172 Hv
Melting Point1450℃Hardness of hard condition140-300 Hv


The alloy is characterized by very low thermal electromotive force (emf) compared to copper.


6J12 is typically used for the manufacturing of resistance standards, precision wire wound resistors, potentiometers, shunts and other electrical and electronic components.

6J12 widely used for precision resistors with the highest requirements, the resistors should be carefully stabilised and the application temperature should not exceed +60℃. Exceeding the maximum working temperature in air may result in a resistance drift generated by oxidizing. Thus, the long-term stability can be affected negatively. As a result, the resistivity as well as the temperature coefficient of the electric resistance may slightly change.

It is also used as low cost replacement material for silver solder for hard metal mounting.The alloy’s low emf vs. copper makes it ideal for use in electrical circuits, especially D.C., where a spurious thermal emf could cause malfunctioning of electronic equipment. Due to the low operating temperature, the temperature coefficient of resistance is controlled to be low over a range of 15 to 35℃ .