Cr20Ni35 NiCr Alloy High Electrical Resistance Coefficient for
Precise Control
Cr20Ni35 is an alloy composed of 20% chromium and 35% nickel, known
for its high temperature resistance and excellent corrosion
resistance. It offers good mechanical strength and ductility,
making it easy to form and machine. With moderate electrical
conductivity, Cr20Ni35 is suitable for a range of applications
including electrical components, heat-resistant parts, and
corrosive environments. Its versatility and durability make it a
popular choice in various industries.
Cr20Ni35 is an alloy characterized by its specific chromium and
nickel content, offering high temperature resistance, excellent
corrosion resistance, good mechanical properties, and moderate
electrical conductivity. These features make it a versatile choice
for a wide range of industrial applications.
Chemical Composition Wt.% Cr20Ni35 | % | Ni | Fe | C | Si | Mn | P | S | Cr |
| Min | 34 | | | 1 | | | | 18 |
| Max | 37 | Rest | 0.08 | 3 | 1 | 0.02 | 0.015 | 21 |
Main characteristics of Ni-Cr and Ni-Cr-Fe electric heating alloys
Type
Performance
| Cr30Ni70 | Cr15Ni60 | Cr20Ni35 | Cr20Ni80 | Cr20Ni30 | Cr25Ni20 |
| Main Chemical composition | Ni | Rest | 55.0-61.0 | 34.0-37.0 | Rest | 30.0-34.0 | 19.0-22.0 |
| Cr | 28.0-31.0 | 15.0-18.0 | 18.0-21.0 | 20.0-23.0 | 18.0-21.0 | 24.0-26.0 |
| Fe | ≤ 1.0 | Rest | Rest | ≤ 1.0 | Rest | Rest |
| Max. continuous service temp. of element (℃) | 1250 | 1150 | 1100 | 1200 | 1100 | 1050 |
| Resistivity at 20 ℃(μΩm) | 1.18±0.05 | 1.12±0.05 | 1.04±0.05 | 1.09±0.05 | 1.06±0.05 | 0.95±0.05 |
| Density(g/cm3) | 8.10 | 8.20 | 7.90 | 8.40 | 7.90 | 7.15 |
| Thermal condyctivity (KJ/m·h·℃) | 45.2 | 45.2 | 43.8 | 60.3 | 43.8 | 43.8 |
| Coefficient of lines expansion (α×10-6/℃) | 17.0 | 17.0 | 19.0 | 18.0 | 19.0 | 19.0 |
| Melting point (approx.)(℃) | 1380 | 1390 | 1390 | 1400 | 1390 | 1400 |
| Elonation at rupture(%) | ＞20 | ＞20 | ＞20 | ＞20 | ＞20 | ＞20 |
| Micrographic structure | Austenite | Austenite | Austenite | Austenite | Austenite | Austenite |
| Magnetic properties | Non-magnetic | Low-magnetic | Low-magnetic | Non-magnetic | Low-magnetic | Non-magnetic |
| Note:The various grades of electric resistance alloy material are
blended with the amountof rare earth, titanium and other trace
elements, to improve the processing performance andextend the
period of the uselife. |
|
Some key features of Cr20Ni35 include:
- High Electrical Resistivity: Cr20Ni35 has a high electrical resistivity, which is beneficial
for applications requiring precise resistance values
- Thermal Stability: The alloy exhibits excellent thermal stability, maintaining
consistent performance across a wide range of temperatures
- Corrosion Resistance: Thanks to its chromium content, Cr20Ni35 offers good resistance
to corrosion, especially in oxidizing environments
- Mechanical Strength: It possesses good mechanical strength and ductility, allowing for
various fabrication processes without compromising its integrity
- Low Temperature Coefficient of Resistance (TCR): Cr20Ni35 has a low TCR, ensuring that its resistance changes
minimally with temperature variations
- Oxidation Resistance: The alloy is resistant to oxidation at high temperatures, which
is crucial for applications in high-heat environments
- Fabrication: Cr20Ni35 can be easily fabricated and formed into various shapes
and sizes, making it suitable for a wide range of applications.
These characteristics make Cr20Ni35 a preferred material in various
industries, particularly those requiring materials with specific
electrical properties and resistance to corrosive environments.
Applications:
Heating Elements: Cr20Ni35 is primarily used as a heating element in periodic heat
treatment furnaces with temperatures below 800°C, such as crawler
heating devices and tempering furnaces
Electric Heating Wire: The alloy is utilized in electric heating wires for electric
heating pipes and household electric heaters. These applications
leverage the superior properties of Cr20Ni35, such as high
resistivity, excellent high-temperature strength, and good
corrosion resistance
Resistance Tape for High-Quality Resistance Boxes: Cr20Ni35 is used in resistance tape for high-quality resistance
boxe
Industrial Heating: It finds application in industrial heating, furnaces, muffles,
retorts, and conveyor systems, as well as heat treating baskets and
fixtures
Electrical Resistance Elements: Due to its high electrical resistivity and temperature stability,
Cr20Ni35 is used in the manufacturing of electrical resistance
elements for various industrial and domestic heating equipment
Precision Resistors: The alloy's resistance stability and low temperature coefficient
make it suitable for precision resistors, particularly in
high-precision measuring instrument
Technical data of wires
| Dia. (mm) | Cross-sectional area (mm²) | Weight/Meter (g/m) | Resistance/Meter at 20 ℃ (Ω/m) | Dia. (mm) | Cross-sectional area (mm²) | Weight/Meter (g/m) | Resistance/Meter at 20 ℃ (Ω/m) |
| 0.018 | 0.000255 | 0.002117 | 3410-4610 | 0.25 | 0.04909 | 0.4074 | 20.88-23.54 |
| 0.020 | 0.000314 | 0.002606 | 2940-3740 | 0.28 | 0.06158 | 0.5111 | 16.64-18.76 |
| 0.022 | 0.000380 | 0.003154 | 2440-3100 | 0.30 | 0.07069 | 0.5867 | 14.49-16.35 |
| 0.025 | 0.000491 | 0.004075 | 1880-2400 | 0.32 | 0.07548 | 0.6265 | 12.74-14.36 |
| 0.028 | 0.000616 | 0.005113 | 1530-1870 | 0.33 | 0.08553 | 0.7099 | 12.20-13.40 |
| 0.030 | 0.000707 | 0.005868 | 1338-1696 | 0.38 | 0.1134 | 0.9412 | 9.13-10.09 |
| 0.032 | 0.000804 | 0.006673 | 1180-1440 | 0.40 | 0.1257 | 1.0433 | 8.24-9.108 |
| 0.035 | 0.000962 | 0.007985 | 981-1200 | 0.41 | 0.132 | 1.0956 | 7.68-8.89 |
| 0.040 | 0.001257 | 0.01043 | 780.7-954.1 | 0.45 | 0.159 | 1.3197 | 6.51-7.196 |
| 0.045 | 0.00159 | 0.0132 | 594-726 | 0.50 | 0.1963 | 1.6293 | 5.273-5.829 |
| 0.050 | 0.001963 | 0.01629 | 499.6-610.6 | 0.55 | 0.2376 | 1.9721 | 4.518-4.994 |
| 0.055 | 0.00238 | 0.01975 | 407-477 | 0.60 | 0.2827 | 2.3464 | 3.797-4.197 |
| 0.063 | 0.00312 | 0.02590 | 321.41-377.31 | 0.65 | 0.3318 | 2.7539 | 3.235-3.575 |
| 0.070 | 0.00385 | 0.03196 | 260.5-305.9 | 0.70 | 0.3848 | 3.1938 | 2.789-3.083 |
| 0.080 | 0.005027 | 0.04172 | 199.5-234.1 | 0.75 | 0.4418 | 3.6669 | 2.43-2.686 |
| 0.090 | 0.006362 | 0.0528 | 157.6-185.0 | 0.80 | 0.5027 | 4.1724 | 2.136-2.36 |
| 0.100 | 0.007854 | 0.0652 | 127.7-149.9 | 0.85 | 0.5674 | 4.7094 | 1.891-2.091 |
| 0.110 | 0.009852 | 0.08177 | 105.5-123.9 | 0.90 | 0.6362 | 5.2805 | 1.687-1.865 |
| 0.120 | 0.01227 | 0.1018 | 88.67-104.1 | 0.95 | 0.7088 | 5.883 | 1.46-1.62 |
| 0.140 | 0.01539 | 0.1277 | 65.85-75.77 | 1.00 | 0.7854 | 6.5188 | 1.367-1.511 |
| 0.150 | 0.01767 | 0.1467 | 56.75-66.63 | 1.10 | 0.9503 | 7.8875 | 1.13-1.26 |
| 0.160 | 0.02011 | 0.01669 | 50.42-58.00 | 1.12 | 0.9852 | 8.1772 | 1.05-1.17 |
| 0.170 | 0.022700 | 0.1884 | 44.18-51.86 | 1.18 | 1.0936 | 9.0769 | 0.95-1.05 |
| 0.180 | 0.02545 | 0.2112 | 40.26-45.40 | 1.20 | 1.313 | 10.8979 | 0.79-0.87 |
| 0.190 | 0.02835 | 0.2353 | 35.37-41.53 | 1.30 | 1.327 | 11.0141 | 0.78-0.86 |
| 0.200 | 0.03142 | 0.2608 | 32.62-36.78 | 1.40 | 1.539 | 12.7737 | 0.70-0.77 |
| 0.212 | 0.035300 | 0.2930 | 28.41-33.35 | 1.50 | 1.767 | 14.6661 | 0.60-0.67 |
| 0.220 | 0.03801 | 0.3155 | 26.65-30.39 | 1.60 | 2.011 | 16.8924 | 0.52-0.58 |
The tolerance or wires diameter
| Wires | Dia.(mm) | Tolerance |
| 0.018-0.025 | ±0.001 |
| 0.028-0.035 | ±0.0015 |
| 0.040-0.055 | ±0.002 |
| 0.070 | ±0.0025 |
| 0.08-0.10 | ±0.003 |
| 0.11-0.14 | ±0.004 |
| 0.16-0.20 | ±0.005 |
| 0.22-0.25 | ±0.006 |
| 0.28-0.30 | ±0.007 |
| 0.32-0.40 | ±0.01 |
| 0.41-0.50 | ±0.015 |
| 0.55-0.80 | +0.02/-0.03 |
| 0.85-1.00 | +0.02/-0.03 |
| 1.10-1.50 | ±0.03 |
| Note:special specification can be produced as per client's request. |
Technical data of ribbon
| Thickness × Width(mm) | Resistance/meter(20 ℃) (Ω/m) | Surface area/ohm (20℃) (cm2/Ω) | Weight/meter (g/m) | Surface area/meter (cm2/m) |
| 0.09x2.5 | 5.27 | 9.84 | 1.72 | 51.8 |
| 0.08x0.2 | 74 | 0.0756 | 0.122 | 5.6 |
| 0.08x0.3 | 49.4 | 0.154 | 0.183 | 7.6 |
| 0.08x0.4 | 37 | 0.259 | 0.244 | 9.6 |
| 0.08x0.5 | 29.6 | 0.392 | 0.305 | 11.6 |
| 0.08x0.6 | 24.7 | 0.551 | 0.367 | 13.6 |
| 0.08x0.7 | 21.2 | 0.737 | 0.428 | 15.6 |
| 0.08x0.8 | 18.5 | 0.951 | 0.489 | 17.6 |
| 0.08x0.9 | 16.5 | 1.19 | 0.55 | 19.6 |
| 0.08x1.0 | 14.8 | 1.46 | 0.611 | 21.6 |
| 0.08x1.2 | 12.3 | 2.07 | 0.733 | 25.6 |
| 0.08x1.5 | 9.87 | 3.2 | 0.916 | 31.6 |
| 0.08x1.8 | 8.23 | 4.57 | 1.1 | 37.6 |
| 0.08x2.0 | 7.4 | 5.62 | 1.22 | 41.6 |
| 0.07x0.2 | 84.6 | 0.0638 | 0.107 | 5.4 |
| 0.07x0.3 | 56.4 | 0.131 | 0.16 | 7.4 |
| 0.07x0.4 | 42.3 | 0.222 | 0.214 | 9.4 |
| 0.07x0.5 | 33.9 | 0.337 | 0.267 | 11.4 |
| 0.07x0.6 | 28.2 | 0.475 | 0.321 | 13.4 |
| 0.07x0.7 | 24.2 | 0.637 | 0.374 | 15.4 |
| 0.07x0.8 | 21.2 | 0.822 | 0.428 | 17.4 |
| 0.07x0.9 | 18.8 | 1.03 | 0.481 | 19.4 |
| 0.07x1.0 | 16.9 | 1.26 | 0.535 | 21.4 |
| 0.07x1.2 | 14.1 | 1.8 | 0.641 | 25.4 |
| 0.07x1.5 | 11.3 | 2.78 | 0.802 | 31.4 |
| 0.06x0.2 | 98.7 | 0.0527 | 0.0916 | 5.2 |
| 0.06x0.3 | 65.8 | 0.109 | 0.137 | 7.2 |
| 0.06x0.4 | 49.4 | 0.186 | 0.183 | 9.2 |
| 0.06x0.5 | 39.5 | 0.284 | 0.229 | 11.2 |
| 0.06x0.6 | 32.9 | 0.401 | 0.275 | 13.2 |
| 0.06x0.7 | 28.2 | 0.539 | 0.321 | 15.2 |
| 0.06x0.8 | 24.7 | 0.697 | 0.367 | 17.5 |
| 0.06x0.9 | 21.9 | 0.875 | 0.412 | 19.2 |
| 0.06x1.0 | 19.7 | 1.07 | 0.458 | 21.2 |
| 0.06x1.2 | 16.5 | 1.53 | 0.55 | 25.2 |
| 0.05x0.2 | 118 | 0.0422 | 0.0764 | 5.00 |
| 0.05x0.3 | 79 | 0.0886 | 0.115 | 7.00 |
| 0.05x0.4 | 59.2 | 0.152 | 0.153 | 9.00 |
| 0.05x0.5 | 47.4 | 0.232 | 0.191 | 11.00 |
| 0.05x0.6 | 39.5 | 0.329 | 0.229 | 13.00 |
| 0.05x0.7 | 33.9 | 0.443 | 0.267 | 15.0 |
| 0.05x0.8 | 29.6 | 0.574 | 0.305 | 17.0 |
| 0.05x0.9 | 16.3 | 0.722 | 0.344 | 19.0 |
| 0.05x1.0 | 23.7 | 0.886 | 0.382 | 21.0 |
| Ribbon is rolled by the wire, the actual cross-sectional area of
the ribbon is smaller 8％ than calculated by the rectangular. |
