Electric Resistance Materials

During the past century since our foundation in 1916, our precision resistance materials have received high evaluations from critics in various fields of the industrial world such as communication tools, automobile parts, precision measurement systems, and home electric products.
We can meet the precise, varied needs of our customers for diverse products with combinations of our processing technologies, such as melting, molding, rolling, wire drawing, and different kinds of advanced coating.
We can supply not only precision resistance wire, ribbon, and bar, but also parts in other forms which our customers need.
We can precisely meet the various needs of our customers by manufacturing precision resistance wire, ribbon, and bar that have a variety of characteristics and functions.

The Categories of Electric Resistance Wire, Ribbon, and Bar

As shown in Table 1, we supply various kinds of electric resistance materials.
Please choose the material that suits your purpose best.

General Resistance Wire, Ribbon, and Bar

1.Copper-Nickel Resistance Wire, Ribbon, Bar
2.Nickel-Chromium Electric Heating Wire, Ribbon, Bar Class 1 / Class 2

Precision Resistance Wire, Ribbon, Bar

1.Manganin Wire, Ribbon, Bar
2.Karmalloy Wire

Categories and Standards of Electric Resistance Materials

Table 1  The features of electric resistance materials
No.Material alloyNameSymbolChemical Composition
Volume resistivity
μΩ · m
Temperature coefficient
X10-6 / ˚C
Tensile strength
1 Cu-Ni
Cu-Ni resistance material CN4945Ni, 2Mn,
rest Cu
0.49 20 410 ~ 540 25 <
30 micro resistance material CN3023Ni, 1.5Mn,
rest Cu
0.30 180 270 ~ 540 20 <
15 micro resistance material CN1510Ni, 1.0Mn,
rest Cu
0.15 420 250 ~ 490 20 <
10 micro resistance materialCN106Ni, 1.0Mn,
rest Cu
0.10 650 250 ~ 440 20 <
5 micro resistance material CN05 2.5Ni, 1.0Mn,
rest Cu
0.05 1200 200 ~ 390 20 <
2 Cu-Mn-Ni
Precision resistance material Manganin CM 12Mn, 2Ni,
rest Cu
0.4410 340 ~ 590 10 <
Precision resistance wire Karmalloy*1 KMW 76Ni, 19Cr,
1.3320 880 ~ 1200 20 <
3 Ni-Cr
Ni-Cr resistance material class 1 NCH-1 19Cr, 2.5Mn,
rest Ni
1.08 50 690 ~ 930 20 <
Ni-Cr resistance material class 2 NCH-257Ni, 16.5Cr,
rest Fe
1.12 150 640 ~ 880 20 <
4 Fe-Cr-Al
Fe-Cr resistance material class 1 FCH-1 24.5Cr, 4.5Al,
rest Fe
1.42 80 640 ~ 880 10 <
Fe-Cr resistance material class 2 FCH-2 19Cr, 3Al,
rest Fe
1.23 150 590 ~ 830 10 <

*1 Karmalloy in this table is our registered trademark.
The 's in the table are to be filled in with P standing for plate, R for ribbon, or W for wire.

Table 2  Required features of precision resistance materials
Features of Alloy Cu-Ni Alloy
Cu-Mn-Ni Alloy
Ni-Cr Alloy
Ni-Cr-Al Alloy
Small temp. coefficient
Large volume resistivity
Small amount at the electromotive force against copper
Fine dia. wires can be drawn excellent mechanical features
Stable resistance over many years

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