NiCr (Nickel-Chromium) and NiCrFe (Nickel-Chromium-Iron) alloys are renowned for their high electric resistance, excellent antioxidant properties, and high tensile strength under high temperatures. These alloys are highly formable and weldable, making them versatile materials for heating elements and resistors used in various industries, including metallurgy, household appliances, and machinery.
Key Characteristics of NiCr Alloys:
High Electric Resistance: NiCr alloys exhibit excellent electrical resistance properties, making them ideal for use in heating elements and resistors.
Oxidation Resistance: These alloys possess strong antioxidant properties, which ensure durability and longevity even in high-temperature environments.
High Tensile Strength at Elevated Temperatures: NiCr alloys can withstand high mechanical stress at elevated temperatures, making them suitable for demanding applications.
Good Formability and Weldability: NiCr alloys are easy to form and weld, ensuring flexibility in manufacturing processes.
Applications:
Metallurgy: Heating elements and resistors in high-temperature furnaces.
Household Electrical Appliances: Heating elements in ovens, toasters, and other electrical devices.
Machinery: Components for industrial machines requiring high resistance to heat and oxidation.
NiCr Alloy Technical Parameters
Property/Type | Cr20Ni80 | Cr30Ni70 | Cr15Ni60 | Cr20Ni35 | Cr20Ni30 |
Main Chemical Composition (%) | |||||
Ni | Balance | Rest | 55.0~61.0 | 34.0~37.0 | 30.0~34.0 |
Cr | 22.0~23.0 | 28.0~31.0 | 15.0~18.0 | 18.0~21.0 | 18.0~21.0 |
Fe | ≤1.0 | ≤1.0 | Balance | Balance | Rest |
Max Continuous Service Temp (°C) | 1200 | 1100 | 1000 | 1000 | 1000 |
Melting Point (°C) | 1400 | 1380 | 1390 | 1390 | 1390 |
Density (g/cm³) | 8.4 | 8.1 | 8.2 | 7.9 | 7.9 |
Resistivity (μΩ·m, 20°C) | 1.09±0.05 | 1.18±0.05 | 1.11±0.05 | 1.04±0.05 | 1.04±0.05 |
Elongation (%) | ≥20 | ≥20 | ≥20 | ≥20 | ≥20 |
Specific Heat Capacity at 20°C (J/g·°C) | 0.44 | 0.461 | 0.494 | 0.5 | 0.5 |
Thermal Conductivity (kJ/m·h·°C) | 60.3 | 45.2 | 45.2 | 43.8 | 43.8 |
Line Expansion Coefficient (a × 10⁻⁶/°C, 20~1000°C) | 18 | 17 | 17 | 19 | 19 |
Microstructure | Austenite | Austenite | Austenite | Austenite | Austenite |
Magnetic Properties | Non-magnetic | Non-magnetic | Non-magnetic | Non-magnetic | Non-magnetic |
NiCr Round Wire Diameter and Characteristics
NiCr wires are commonly available in various diameters and offer a range of electrical resistivity and mass characteristics, making them adaptable for different industrial applications. Below is a table detailing the wire diameter, corresponding cross-sectional area, and key properties of Cr20Ni80, Cr15Ni60, Cr20Ni35, and Cr20Ni30 alloys.
Diameter (mm) | Cross-sectional Area (mm²) | Cr20Ni80 (kg/m) | Cr20Ni80 (Ω/m, 20°C) | Cr15Ni60 (kg/m) | Cr15Ni60 (Ω/m, 20°C) | Cr20Ni35/Cr20Ni30 (kg/m) | Cr20Ni35/Cr20Ni30 (Ω/m, 20°C) |
0.1 | 0.007854 | 0.00006597 | 138.8 | 0.0000644 | 142.6 | 0.0000616 | 132.4 |
0.12 | 0.01131 | 0.000095 | 96.38 | 0.00009274 | 99.03 | 0.0000892 | 91.96 |
0.15 | 0.01767 | 0.0001484 | 61.68 | 0.0001449 | 63.38 | 0.00014 | 58.85 |
0.17 | 0.0227 | 0.0001907 | 48.02 | 0.0001861 | 49.34 | 0.000179 | 45.82 |
0.19 | 0.02835 | 0.0002382 | 38.44 | 0.0002325 | 39.5 | 0.000224 | 36.86 |
0.21 | 0.03464 | 0.0002909 | 31.47 | 0.000284 | 32.34 | 0.0003 | 27.36 |
0.25 | 0.04909 | 0.0004809 | 22.21 | 0.0004025 | 22.82 | 0.000388 | 21.19 |
0.27 | 0.05726 | 0.0005548 | 19.04 | 0.0004695 | 19.56 | 0.000487 | 16.89 |
0.29 | 0.06605 | 0.0004809 | 16.5 | 0.0005416 | 16.96 | 0.000558 | 14.71 |
0.31 | 0.07548 | 0.000634 | 14.44 | 0.0006189 | 14.84 | 0.000635 | 12.93 |
0.35 | 0.09621 | 0.0008082 | 11.33 | 0.0007889 | 11.64 | 0.00076 | 10.81 |
Conclusion:
NiCr and NiCrFe alloys are versatile, high-performance materials that meet the stringent demands of industrial heating elements and resistors. Their robust mechanical properties, high resistance, and excellent formability make them essential for applications in high-temperature environments. Whether in metallurgy, household appliances, or machinery, these alloys offer reliability and durability.