6J40 Constantan-Type Copper-Nickel Alloy Resistor Element for Industrial Applications
6J40 Constantan-Type Copper-Nickel Alloy Resistor Element for Industrial Applications
A constant alloy is a type of metal alloy that is designed to maintain its properties under a wide range of conditions, often focused on maintaining consistent electrical, thermal, or mechanical performance over time. These alloys are commonly used in electrical applications, thermocouples, resistance wires, and heating elements due to their stable properties.
One of the best-known constant alloys is Constantan, a copper-nickel alloy, which is particularly famous for its constant electrical resistance over a wide temperature range.
The defining feature of a constant alloy, like Constantan, is its ability to maintain stable electrical and thermal properties over a wide range of conditions, including temperature fluctuations. These alloys are essential in precise, high-performance applications such as temperature sensing (thermocouples), resistor manufacturing, and heating elements, where consistent and reliable material performance is critical.
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:
- High Voltage Capability:
The 6J40 is designed to handle high voltage levels, making it suitable for applications requiring substantial electrical input.
- Robust Current Handling:
This component can manage significant current flows, ensuring reliable performance even under heavy loads.
- Low Noise Operation:
The 6J40 operates with minimal noise, which is beneficial for applications where noise interference could be problematic.
- Stable Performance:
It offers stable performance characteristics, ensuring consistent operation over extended periods.
- Versatile Application:
Due to its features, the 6J40 can be used in a variety of applications, including but not limited to power amplification and signal processing.
Note:
The 6J40's specific features make it a valuable component in electrical and electronic systems, particularly where high voltage, current handling, and low noise are essential.
Applications:
- Electronic and Electrical Industry: 6J40 alloy is used for manufacturing high-precision electronic components such as resistors, capacitors, and connectors.
- Marine and Ocean Engineering: Due to its excellent corrosion resistance, 6J40 alloy is employed in the marine and ocean engineering sectors to produce seawater-resistant parts.
- Petrochemical Industry: In the petrochemical field, 6J40 alloy is utilized for manufacturing corrosion-resistant pipelines, valves, and other equipment.
- Aerospace Industry: This alloy finds application in the aerospace sector for producing high-temperature and corrosion-resistant components like engine exhaust manifolds.
- Other Uses: 6J40 is also suitable for use in AC circuits as precision resistors, sliding resistors, resistance strain gauges, and for thermocouples and thermocouple compensation.
- These diverse applications highlight the versatility and utility of 6J40 alloy across various industries.
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 | |||||
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