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Precision Resistance Wire 6J40 Constantan Flat Wire for Precision Temperature Measurement and Scientific Applications
The 6J40 Constantan flat wire is a specialized form of Constantan, a copper-nickel alloy primarily used in high-precision electrical applications such as thermocouples, resistors, and strain gauges. The 6J40 designation refers to a specific grade or alloy mix within the broader family of Constantan materials, and the flat wire form factor indicates it is shaped for specific uses in applications like precision measurement and temperature sensing.
The flat wire form factor of 6J40 Constantan allows for greater surface area per unit of wire length, making it ideal for applications like heating elements (which require good heat dissipation) and precise measurement applications like strain gauges or resistor networks.
Chemical composition
Name | Code | Main Composition(%) | Density | |||
Cu | Mn | Ni | Cr | g/mm2 | ||
Constantan | 6J40 | Bal. | 1~2 | 39~41 | -- | 8.9 |
Properties
Name | Code | Resistivity(20℃)(μΩm) | Temp.Coeff.Of Resistance (20℃)(α×10-6/℃) | (0~100℃) Thermal EMF vs. Copper (μv/℃) | Max. Working Temp. (℃) | Elongation(%) | Tensile Strength(N/mm2) |
Constantan | 6J40 | 0.48±0.03 | -40~+40 | 45 | ≤500 | ≥15 | ≥390 |
Diameter and Tolerance
Diameter | 0.02~0.028 | 0.032~0.10 | 0.112~0.28 | 0.315~0.50 | 0.56~1.0 | 1.06~1.60 | 1.70~2.12 | 2.24~3.00 | 3.15~4.50 |
Tolerance | ±0.002 | ±0.003 | ±0.005 | ±0.010 | ±0.015 | ±0.020 | ±0.025 | ±0.030 | ±0.035 |
Some key features of 6J40 include:
6J40 Constantan flat wire offers consistent electrical resistance over a wide range of temperatures, a hallmark of Constantan alloys. This stable resistance makes it ideal for precision electrical applications, especially where resistance must remain constant despite temperature fluctuations.
6J40 Constantan has a low temperature coefficient of resistance, meaning its electrical resistance changes very little with temperature changes. This is critical in applications like thermocouples, resistors, and strain gauges, where temperature-induced resistance variations can lead to measurement errors.
6J40 Constantan is typically composed of approximately 55% copper and 45% nickel. This copper-nickel blend provides a balanced mix of good electrical conductivity and excellent mechanical strength, while maintaining low resistance to corrosion.
6J40 Constantan has excellent resistance to corrosion, particularly in moisture and chemical environments. This makes it suitable for long-term use in challenging conditions, including outdoor or industrial applications where environmental exposure is a factor.
Due to its thermoelectric properties, 6J40 Constantan flat wire is widely used in thermocouples for temperature measurement. When paired with other metals (such as Chromel or Alumel), the wire generates a voltage that is proportional to the temperature difference between the two materials. This makes it ideal for high-precision temperature sensing and temperature control systems.
The alloy is known for its high tensile strength, which makes 6J40 Constantan flat wire durable and resistant to mechanical stress. It maintains its shape and functionality even under continuous use, making it suitable for applications like resistive heating elements and structural sensors.
6J40 Constantan flat wire is ductile, meaning it can be drawn into very fine wires or formed into flat shapes without breaking or becoming brittle. This flexibility makes it suitable for use in wound resistors, strain gauges, and other precision components that require fine manipulation.
6J40 Constantan is non-magnetic, which is essential for applications where magnetic interference could distort performance, such as in sensitive measuring instruments or electronic devices where external magnetic fields must be minimized.
The material operates effectively across a wide temperature range, typically from -200°C to 250°C (or higher, depending on specific alloy formulations and application conditions). This makes it versatile for use in both low-temperature and high-temperature environments, typical in industrial and scientific settings.
Applications:
Constantan (6J40) Technical data of wires
Dia(m) | Cross-sectional area(m²) | Weight/m (g/m) | Resistance/m at 20℃(Ω/m) | Dia(m) | Cross-sectional area(m²) | Weight/m (g/m) | Resistance/m at 20℃(Ω/m) |
0.020 | 0.000314 | 0.00279 | 1375-1681 | 0.224 | 0.03941 | 0.350 | 11.4-12.9 |
0.022 | 0.000318 | 0.00337 | 1136-1389 | 0.250 | 0.04909 | 0.436 | 9.19-10.37 |
0.025 | 0.000491 | 0.00434 | 880-1076 | 0.280 | 0.06158 | 0.5468 | 7.33-8.26 |
0.028 | 0.000616 | 0.00547 | 702-857 | 0.315 | 0.07793 | 0.6920 | 5.85-6.47 |
0.032 | 0.000804 | 0.00714 | 549-645 | 0.355 | 0.09898 | 0.8789 | 4.61-5.09 |
0.036 | 0.001018 | 0.00904 | 434-509 | 0.400 | 0.12570 | 1.116 | 3.63-4.01 |
0.040 | 0.001257 | 0.01116 | 351-413 | 0.450 | 0.15900 | 1.412 | 2.87-3.17 |
0.045 | 0.001509 | 0.01412 | 278-326 | 0.500 | 0.19630 | 1.744 | 2.32-2.57 |
0.050 | 0.001963 | 0.01744 | 225-264 | 0.560 | 0.24630 | 2.19 | 1.87-2.03 |
0.056 | 0.002463 | 0.02187 | 179-210 | 0.630 | 0.31170 | 2.77 | 1.48-1.60 |
0.063 | 0.003117 | 0.02768 | 142-166 | 0.710 | 0.39590 | 3.52 | 1.16-1.26 |
0.071 | 0.003959 | 0.03516 | 112-131 | 0.750 | 0.44180 | 3.92 | 1.04-1.13 |
0.080 | 0.005027 | 0.04464 | 87.9-103.1 | 0.800 | 0.50270 | 4.46 | 0.917-0.993 |
0.090 | 0.006362 | 0.05650 | 69.4-81.5 | 0.850 | 0.56740 | 5.04 | 0.812-0.880 |
0.100 | 0.007854 | 0.06970 | 56.2-66.0 | 0.900 | 0.63620 | 5.65 | 0.724-0.785 |
0.112 | 0.009852 | 0.08749 | 45.3-52.1 | 0.950 | 0.70880 | 6.29 | 0.650-0.704 |
0.125 | 0.012270 | 0.10900 | 36.4-41.9 | 1.000 | 0.78540 | 6.97 | 0.587-0.636 |
0.140 | 0.015390 | 0.13670 | 29.0-33.4 | 1.060 | 0.88250 | 7.84 | 0.522-0.566 |
0.150 | 0.017670 | 0.15690 | 25.3-29.1 | 1.120 | 0.98520 | 8.75 | 0.468-0.507 |
0.160 | 0.020110 | 0.17850 | 22.2-25.5 | 1.180 | 1.09400 | 9.71 | 0.421-0.456 |
0.170 | 0.022700 | 0.20160 | 19.7-22.6 | 1.250 | 1.22700 | 10.9 | 0.375-0.407 |
0.180 | 0.025450 | 0.22600 | 17.5-20.2 | 1.320 | 1.36800 | 12.15 | 0.337-0.365 |
0.190 | 0.028350 | 0.25200 | 15.7-18.1 | 1.400 | 1.53900 | 13.67 | 0.299-0.324 |
0.200 | 0.031420 | 0.27900 | 14.4-16.2 | 1.500 | 1.76700 | 15.69 | 0.261-0.282 |
0.212 | 0.035300 | 0.31350 | 12.8-14.4 | 1.600 | 2.01100 | 17.86 | 0.229-0.248 |
Constantan strip resistance value (Ω/m)
Width Thickness | 6.3 | 8.0 | 10.0 | 12.5 | 16.0 | 20.0 | 25.0 | 31.5 | 40.0 |
0.180 | 0.150 | ||||||||
0.200 | 0.405 | ||||||||
0.224 | 0.362 | 0.2850 | |||||||
0.250 | 0.324 | 0.2550 | 0.196 | ||||||
0.280 | 0.289 | 0.2280 | 0.175 | ||||||
0.315 | 0.257 | 0.2030 | 0.155 | 0.124 | |||||
0.355 | 0.228 | 0.1800 | 0.138 | 0.110 | |||||
0.400 | 0.203 | 0.1600 | 0.122 | 0.980 | 0.0765 | ||||
0.450 | 0.180 | 0.1420 | 0.109 | 0.0871 | 0.0680 | 0.0544 | 0.0435 | ||
0.500 | 0.162 | 0.1280 | 0.098 | 0.0784 | 0.0612 | 0.0490 | 0.0392 | ||
0.560 | 0.145 | 0.1140 | 0.0875 | 0.0700 | 0.0547 | 0.0437 | 0.0350 | ||
0.630 | 0.129 | 0.1010 | 0.0777 | 0.0622 | 0.0486 | 0.0389 | 0.0311 | ||
0.710 | 0.114 | 0.0900 | 0.0690 | 0.0552 | 0.0431 | 0.0345 | 0.0276 | ||
0.800 | 0.101 | 0.0800 | 0.0612 | 0.0490 | 0.0383 | 0.0306 | 0.0245 | 0.0194 | 0.0153 |
0.900 | 0.090 | 0.0710 | 0.0544 | 0.0435 | 0.0340 | 0.0272 | 0.0218 | 0.0173 | 0.0136 |
1.000 | 0.081 | 0.0640 | 0.0490 | 0.0392 | 0.0306 | 0.0245 | 0.0196 | 0.0155 | 0.0122 |
1.120 | 0.072 | 0.0570 | 0.0437 | 0.0350 | 0.0273 | 0.0219 | 0.0175 | 0.0139 | 0.0109 |
1.250 | 0.065 | 0.0510 | 0.0392 | 0.0313 | 0.0245 | 0.0196 | 0.0157 | 0.0124 | 0.0098 |
1.400 | 0.058 | 0.0460 | 0.0350 | 0.0280 | 0.0219 | 0.0175 | 0.0140 | 0.0111 | 0.0088 |
1.600 | 0.051 | 0.0400 | 0.0306 | 0.0245 | 0.0191 | 0.0153 | 0.0122 | 0.0097 | 0.0077 |
1.800 | 0.045 | 0.0350 | 0.0272 | 0.0218 | 0.0170 | 0.0136 | 0.0109 | 0.0086 | 0.00680 |
2.000 | 0.041 | 0.0320 | 0.0245 | 0.0196 | 0.0153 | 0.0122 | 0.0098 | 0.0078 | 0.0061 |
Constantan&Manganin wire table
Dia.(mm) | Sectional area nominal value(mm2) | Resistance per meter (Ω/m) | ||||||||
6J12X | 6J8X | 6J13X | 6J40X | |||||||
Nominal value(mm) | Tolerance | Nominal value (Ω/m) | Tolerance | Nominal value (Ω/m) | Tolerance | Nominal value (Ω/m) | Tolerance | Nominal value (Ω/m) | Tolerance | |
0.020 | ±0.002 | 0.000314 | 1496 | ±10% | 1528 | ±10% | ||||
0.022 | 0.000380 | 1236 | 1263 | |||||||
0.025 | 0.000491 | 957 | 978 | |||||||
0.028 | 0.000616 | 763 | 780 | |||||||
0.032 | ±0.003 | 0.000804 | 584 | ±8% | ±8% | ±8% | 597 | ±8% | ||
0.036 | 0.001018 | 462 | 472 | |||||||
0.040 | 0.001257 | 374 | 382 | |||||||
0.045 | 0.001590 | 296 | 302 | |||||||
0.050 | 0.001963 | 239 | 244 | |||||||
0.056 | 0.002463 | 191 | 195 | |||||||
0.063 | 0.003117 | 151 | 154 | |||||||
0.071 | 0.003959 | 119 | 121 | |||||||
0.080 | 0.005027 | 93.5 | 69.6 | 87.5 | 95.5 | |||||
0.090 | 0.006362 | 73.9 | 55.0 | 69.2 | 75.5 | |||||
0.100 | 0.007854 | 59.8 | 44.6 | 56.0 | 61.1 | |||||
0.112 | ±0.005 | 0.009852 | 47.7 | ±7% | 35.5 | ±7% | 44.7 | ±7% | 48.7 | ±7% |
0.125 | 0.01227 | 38.3 | 28.5 | 35.9 | 39.1 | |||||
0.140 | 0.01539 | 30.5 | 22.7 | 28.6 | 31.2 | |||||
0.160 | 0.02011 | 23.4 | 17.4 | 21.9 | 23.9 | |||||
0.180 | 0.02545 | 18.5 | 13.8 | 17.3 | 18.9 | |||||
0.200 | ±0.005 | 0.03142 | 15.0 | ±6% | 11.1 | ±6% | 14.0 | ±6% | 15.3 | ±6% |
0.224 | 0.03941 | 11.9 | 8.88 | 11.2 | 12.2 | |||||
0.250 | 0.04909 | 9.57 | 7.13 | 8.96 | 9.78 | |||||
0.280 | 0.06158 | 7.63 | 5.68 | 7.15 | 7.80 | |||||
0.315 | ±0.010 | 0.007793 | 6.03 | ±5% | 4.49 | ±5% | 5.65 | ±5% | 6.16 | ±5% |
0.355 | 0.09898 | 4.75 | 3.54 | 4.45 | 4.85 | |||||
0.400 | 0.1257 | 3.74 | 2.79 | 3.50 | 3.82 | |||||
0.450 | 0.1590 | 2.96 | 2.20 | 2.77 | 3.02 | |||||
0.500 | ±0.015 | 0.1963 | 2.39 | ±4% | 1.78 | ±4% | 2.24 | ±4% | 2.44 | ±4% |
0.560 | 0.2463 | 1.91 | 1.42 | 1.79 | 1.95 | |||||
0.630 | 0.3117 | 1.51 | 1.12 | 1.41 | 1.51 | |||||
0.710 | 0.3959 | 1.19 | 0.884 | 1.11 | 1.21 | |||||
0.750 | 0.4418 | 1.06 | 0.792 | 1.00 | 1.09 | |||||
0.800 | 0.5027 | 0.935 | 0.696 | 0.875 | 0.955 | |||||
0.850 | 0.5674 | 0.828 | 0.617 | 0.775 | 0.846 | |||||
0.900 | 0.6362 | 0.739 | 0.550 | 0.692 | 0.755 | |||||
0.950 | 0.7088 | 0.663 | 0.494 | 0.621 | 0.677 | |||||
1.000 | 0.7854 | 0.598 | 0.446 | 0.560 | 0.611 | |||||
1.060 | ±0.020 | 0.8852 | 0.533 | ±4% | 0.397 | ±4% | 0.499 | ±4% | 0.544 | ±4% |
1.120 | 0.9852 | 0.477 | 0.355 | 0.447 | 0.487 | |||||
1.180 | 1.094 | 0.430 | 0.320 | 0.402 | 0.439 | |||||
1.250 | 1.227 | 0.383 | 0.285 | 0.359 | 0.391 | |||||
1.320 | 1.368 | 0.343 | 0.256 | 0.322 | 0.351 | |||||
1.400 | 1.539 | 0.305 | 0.227 | 0.286 | 0.312 | |||||
1.500 | 1.767 | 0.266 | 0.198 | 0.249 | 0.272 | |||||
1.600 | 2.011 | 0.234 | 0.174 | 0.219 | 0.239 | |||||
1.700 | ±0.025 | 2.270 | 0.207 | ±4% | 0.154 | ±4% | 0.194 | ±4% | 0.211 | ±4% |
1.800 | 2.545 | 0.185 | 0.138 | 0.173 | 0.189 | |||||
1.900 | 2.835 | 0.166 | 0.123 | 0.155 | 0.169 | |||||
2.000 | 3.142 | 0.15 | 0.111 | 0.140 | 0.153 | |||||
2.120 | 3.530 | 0.133 | 0.0992 | 0.125 | 0.136 | |||||
2.240 | ±0.030 | 3.941 | 0.119 | ±4% | 0.0888 | ±4% | 0.112 | ±4% | 0.122 | ±4% |
2.360 | 4.374 | 0.107 | 0.0800 | 0.101 | 0.110 | |||||
2.500 | 4.909 | 0.0957 | 0.0713 | 0.0896 | 0.0978 | |||||
2.650 | 5.515 | 0.0852 | 0.0635 | 0.0798 | 0.0870 | |||||
2.800 | 6.158 | 0.0763 | 0.0568 | 0.0715 | 0.0780 | |||||
3.000 | 7.069 | 0.0665 | 0.0495 | 0.0622 | 0.0679 | |||||
3.150 | ±0.035 | 7.793 | 0.0603 | ±4% | 0.0449 | ±4% | 0.0565 | ±4% | 0.0616 | ±4% |
3.350 | 8.814 | 0.0533 | 0.0397 | 0.0499 | 0.0545 | |||||
3.550 | 9.898 | 0.0475 | 0.0354 | 0.0445 | 0.0485 | |||||
3.750 | 11.04 | 0.0426 | 0.0317 | 0.0398 | 0.0435 | |||||
4.000 | 12.57 | 0.0374 | 0.0279 | 0.0350 | 0.0382 | |||||
4.250 | 14.19 | 0.0331 | 0.0247 | 0.0310 | 0.0338 | |||||
4.500 | 15.90 | 0.0296 | 0.0220 | 0.0277 | 0.0302 | |||||
4.750 | ±0.040 | 17.72 | 0.0265 | ±4% | 0.0198 | ±4% | 0.0248 | ±4% | 0.0271 | ±4% |
5.000 | 19.63 | 0.0239 | 0.0178 | 0.0224 | 0.0244 | |||||
5.300 | ±0.050 | 22.06 | 0.0213 | ±4% | 0.0159 | ±4% | 0.0199 | ±4% | 0.0218 | ±4% |
5.600 | 24.63 | 0.0191 | 0.0142 | 0.0179 | 0.0195 | |||||
6.000 | ±0.060 | 28.27 | 0.0166 | ±4% | 0.0124 | ±4% | 0.0156 | ±4% | 0.017 | ±4% |
6.300 | 31.17 | 0.0151 | 0.0112 | 0.0141 | 0.0154 |