Nickel-Chromium Electrical Resistance Alloy Overview
Nickel-chromium (NiCr) electrical resistance alloys combine stable electrical resistivity with oxidation resistance, form stability and workable ductility. They are supplied as wire, strip and ribbon for heating elements and resistance components. Grade selection must consider element temperature, atmosphere, electrical load, dimensions, forming route and expected service life.
| Item |
Details |
| Product family |
Nickel-chromium and nickel-chromium-iron electrical resistance alloys |
| Main forms |
Round wire, flat wire, strip and ribbon |
| Typical standard |
ASTM B344 for drawn or rolled nickel-chromium and nickel-chromium-iron alloys used in electrical heating elements |
| Order basis |
Alloy grade, dimensions, resistance requirement, condition, quantity, testing and certificate |
Grades and Selection Direction
| Grade |
Procurement Guidance |
| Ni80Cr20 |
High-nickel Ni-Cr grade for electrical heating elements requiring oxidation resistance and stable resistance characteristics |
| Ni70Cr30 |
Higher-chromium Ni-Cr grade considered for demanding furnace atmospheres and elevated-temperature elements |
| Ni60Cr15 |
Ni-Cr-Fe resistance alloy balancing electrical performance, workability and cost |
| Ni35Cr20 / Ni30Cr20 |
Ni-Cr-Fe grades for resistance and heating applications selected according to design temperature and atmosphere |
| Selection note |
Maximum element temperature is not a universal design limit; it varies with wire size, surface loading, atmosphere, cycling and installation |
Typical Composition and Physical Properties
The following values preserve the existing product data as typical reference information. Final limits and acceptance criteria are confirmed against the ordered grade, applicable standard and material certificate.
| Property |
Ni80Cr20 |
Ni70Cr30 |
Ni60Cr15 |
Ni35Cr20 |
Ni30Cr20 |
| Nickel (wt.%) |
Balance |
Balance |
55.0-61.0 |
34.0-37.0 |
30.0-34.0 |
| Chromium (wt.%) |
20.0-23.0 |
28.0-31.0 |
15.0-18.0 |
18.0-21.0 |
18.0-21.0 |
| Iron (wt.%) |
≤1.0 |
≤1.0 |
Balance |
Balance |
Balance |
| Typical maximum service temperature |
1200°C |
1250°C |
1150°C |
1100°C |
1100°C |
| Melting point |
1400°C |
1380°C |
1390°C |
1390°C |
1390°C |
| Density |
8.40 g/cm3 |
8.10 g/cm3 |
8.20 g/cm3 |
7.90 g/cm3 |
7.90 g/cm3 |
| Electrical resistivity at 20°C |
1.09 µΩ·m |
1.18 µΩ·m |
1.12 µΩ·m |
1.00 µΩ·m |
1.04 µΩ·m |
| Elongation |
≥20% |
≥20% |
≥20% |
≥20% |
≥20% |
| Specific heat |
0.440 J/(g·°C) |
0.461 J/(g·°C) |
0.494 J/(g·°C) |
0.500 J/(g·°C) |
0.500 J/(g·°C) |
| Thermal conductivity |
60.3 kJ/(m·h·°C) |
45.2 kJ/(m·h·°C) |
45.2 kJ/(m·h·°C) |
43.8 kJ/(m·h·°C) |
43.8 kJ/(m·h·°C) |
| Linear expansion coefficient |
18.0 ×10-6/°C |
17.0 ×10-6/°C |
17.0 ×10-6/°C |
19.0 ×10-6/°C |
19.0 ×10-6/°C |
| Microstructure |
Austenitic |
Austenitic |
Austenitic |
Austenitic |
Austenitic |
| Magnetic property |
Nonmagnetic |
Nonmagnetic |
Nonmagnetic |
Nonmagnetic |
Nonmagnetic |
Supply Forms and Dimensional Control
| Item |
Details |
| Round wire |
Diameter, tolerance, coil or spool size, temper and surface condition specified with the inquiry |
| Flat wire / ribbon |
Thickness, width, edge condition, camber and coil configuration confirmed before production |
| Strip |
Thickness, width, slit edge, coil ID/OD and coil weight supplied to the agreed order specification |
| Condition |
Annealed, cold-drawn or customer-specified condition subject to grade and dimension |
| Electrical control |
Resistance or resistivity requirement, test temperature, gauge length and acceptance tolerance must be defined |
Discuss NiCr Grade, Dimensions and Resistance Requirements
Heating Element and Resistance Applications
| Item |
Details |
| Industrial furnaces |
Coiled or formed resistance elements for heat-treatment, ceramic, glass and general industrial furnace equipment |
| Domestic and commercial appliances |
Heating elements for water heating, irons, dryers, ovens and related equipment |
| Tubular and cartridge heaters |
Resistance wire used inside insulated metal-sheathed heating assemblies |
| Process equipment |
Heating and temperature-control components for plastics processing, sealing and thermal systems |
| Engineering note |
Final element design must account for watt density, support spacing, atmosphere, cycling and heat dissipation |
Quality Inspection and Documentation
| Item |
Details |
| Material identity |
Grade and heat or lot traceability controlled through production and packing |
| Chemical composition |
Verified against the ordered specification and reported when required |
| Dimensions |
Diameter or thickness/width, tolerance and coil configuration inspected |
| Electrical properties |
Resistance or resistivity tested using the agreed method and reference temperature |
| Surface and workmanship |
Visual inspection for surface condition, edge quality, winding and handling damage |
| Documents |
Material certificate, inspection report and additional third-party inspection available when specified before quotation |
Packaging and Export Delivery
| Item |
Details |
| Wire packaging |
Spools, coils or drums selected according to diameter, unit weight and feeding requirement |
| Strip and ribbon |
Coils protected against telescoping, edge damage, moisture and contamination |
| Identification |
Alloy grade, heat or lot number, dimensions, net weight and order reference marked |
| Export protection |
Moisture barrier and reinforced outer packing selected for route and handling conditions |
| Delivery review |
Unit weight, destination, lifting method and documentation confirmed before dispatch |
RFQ Confirmation Checklist
| Please Provide |
Required Detail |
| Alloy grade |
Ni80Cr20, Ni70Cr30, Ni60Cr15, Ni35Cr20, Ni30Cr20 or required equivalent |
| Product form |
Round wire, flat wire, strip or ribbon |
| Dimensions |
Diameter or thickness × width, tolerances and coil/spool details |
| Electrical requirement |
Target resistance/resistivity, reference temperature, tolerance and test method |
| Service conditions |
Element temperature, atmosphere, watt density, cycling and expected life |
| Condition and processing |
Temper, surface, edge, forming or welding requirements |
| Quality and delivery |
Quantity, certificate, inspection, packing, destination and required date |
Request a Nickel-Chromium Resistance Alloy Quote
Values shown are typical reference data and do not replace the applicable material standard, purchase specification or engineering design review.
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