China Constantan Wire / CuNi44 Resistance Alloy Wire for Precision Resistors Manufacture and Factory

Constantan Wire / CuNi44 Resistance Alloy Wire for Precision Resistors

Short Description:

Constantan wire CuNi44 (55% Cu, 44% Ni, 1% Mn), very low temperature coefficient of resistance (TCR < ±40 ppm/°C) and high thermal EMF vs copper. Ideal for precision wirewound resistors, thermocouple extension leads, and low‑drift current sensing. Diameter from 0.05mm to 2.0mm, supplied on spools or in straightened lengths. Good solderability and long‑term stability.

Send email to us

Product Detail

FAQ

Product Tags

Product Description

CuNi44 Constantan Resistance Alloy Wire for Precision Resistors & Thermocouples

Product Description:

CuNi44 alloy (also known as Constantan, Alloy 300, Cuprothal 294, Cupron) is a copper-nickel resistance alloy with 44% nickel content. It features an extremely low temperature coefficient of resistance (TCR), making it ideally suited for precision resistors, shunts, thermocouple extension wires, and low-temperature heating applications.

Our CuNi44 wire offers excellent resistance consistency, good weldability, and long-term stability. It is widely used in electrical instruments, automotive sensors, aerospace control systems, and laboratory equipment.

We can supply round wire, flat wire, and ribbon/strip in various diameters and tolerances

Chemical Content, %

Ni	Mn	Fe	Si	Cu	Other	ROHS Directive
						Cd	Pb	Hg	Cr
44	1.50%	0.5	-	Bal	-	ND	ND	ND	ND

Mechanical Properties

Max Continuous Service Temp	400ºC
Resisivity at 20ºC	0.49±5%ohm mm2/m
Density	8.9 g/cm3
Thermal Conductivity	-6(Max)
Melting Point	1280ºC
Tensile Strength,N/mm2 Annealed,Soft	340~535 Mpa
Tensile Strength,N/mm3 Cold Rolled	680~1070 Mpa
Elongation(anneal)	25%(Min)
Elongation(cold rolled)	≥Min)2%(Min)
EMF vs Cu, μV/ºC (0~100ºC)	-43
Micrographic Structure	austenite
Magnetic Property	Non

Applications:

Precision wirewound resistors and shunts
Thermocouple extension wire (Type S, R, B – compensating conductors)
Low-voltage circuit breakers and thermal overload relays
Low-temperature heating elements (e.g., floor heating cables)
Automotive sensors and instrument shunts
Laboratory resistance standards

Why Choose Our CuNi44 Wire?

Strict raw material control (virgin nickel & copper, no recycled scrap)
Advanced drawing and annealing process ensures uniform resistivity and smooth surface
±0.005 mm tolerance available for precision applications
RoHS, REACH, SGS test report can be provided
Short lead time: 15-20 days for bulk orders

Constantan Wire / CuNi44 Resistance Alloy Wire for Precision Resistors