Constantan wire is a resistance alloy with copper and nickel as the main component.
Features: It has a low temperature coefficient of resistance, a wide operating temperature range (below 480°C), good processing performance, and good welding performance.
Mainly used for: making electronic components in instrumentation, electronics and industrial equipment.
In addition, there is a new constantan resistance alloy, which is a copper-iron-based same alloy. It has the same resistivity as Constantan, basically similar resistance temperature coefficient, and the same operating temperature. Compared with constantan resistance alloy, new constantan has the advantage of low price because it does not contain the higher price of nickel, but its oxidation resistance is worse than that of constantan. It can replace constantan wire resistance alloy in many aspects.
Function in the design of regulated power supply: over-current protection, test load current.
Main technical properties of constantan, new constantan, copper-manganese resistance alloy (GB/T1234-95 standard):
Performance / grade
Constantan 6J40
New Constantan 6J11
Manganese 6J12
F1 manganese copper 6J8
F2 manganese copper 6J13
Main chemical composition%
Ni
39-41
__
2-3
___
2-5
Mn
1-2
10.5-12.5
11-13
8-10
11-13
Cu
margin
margin
margin
margin
margin
other
__
Al:2.5-4.5
Fe:1.0-1.6
__
Si:1-2
__
Component applicable temperature ℃
5-500
5-500
5-45
10-80
10-80
Density g/m3
8.88
8.00
8.44
8.70
8.40
Resistivity.m, 20℃
0.48±0.03
0.48±0.03
0.46±0.03
0.35±0.05
0.44±0.04
Temperature Coefficient of Resistance
aí10-6/℃
+40
-40
+80
-80
+20
-3
+10
-5
40
Thermal electromotive force for copper
V/℃(0-100℃)
45
2
1
2
2
Elongation% (>0.5)
≥15
≥15
≥15
≥15
≥15
organize
Austenite
Austenite
Austenite
Austenite
Austenite
magnetic
Non-magnetic
Non-magnetic
Non-magnetic
Non-magnetic
Non-magnetic
Constantan wire (6J40) related technical parameters
Diameter (mm)
Resistance per meter (Ω/m)
Surface area per meter (cm²/m)
Cross-sectional area (mm²)
2.0
0.153
62.8
3.14
1.8
0.189
56.5
2.54
1.7
0.212
53.4
2.27
1.5
0.272
47.1
1.77
1.4
0.305
43.9
1.54
1.2
0.424
37.7
1.13
1.0
1.611
31.4
0.785
0.9
0.755
28.3
0.636
0.8
0.951
25.1
0.503
