Common trade names NiCr 70/30, Resistohm 70, Nikrothal 70, Chromel 70/30, HAI-NiCr 70, Cronix 70, Inalloy 70, X30H70.
NiCr 70 30 (Werkstoff Nr 2.4658) is an austenitic Nickel-Chromium alloy for use at temperatures up to 1250°C. The 70/30 alloy is characterized by high resistivity and good oxidation resistance. It has good ductility after use and excellent weldability.
Chemical composition
Nickel Ni 67-70% | Chromium Cr 29-32% | Iron Fe 1.0% | Silicon Si 1.0-2.5% | Manganese Mn 1.0% | Copper Cu 0.5% | Carbon C 0.1% | Cupper Cu 0.4% | Aluminium Al 0.1% |
Physical properties
Density at Room°C |
Electrical Resistivity at 20°C |
Melting Point °C |
Max Continuous Operating Temperature in Air °C |
Magnetic Properties |
8.2 g/cm3 | 1.16(1.19)* microhm-m | 1380 | 1200 | The Material is Non-Magnetic |
*Electrical Resistivity 1.16 Ω mm2/m corresponds to an Oxidized Annealed condition Electrical Resistivity 1.19 Ω mm2/m corresponds to a Bright Annealed condition |
Mechanical properties
NiCr 80 20 Wire, mm |
Yield Strength Rp0.2 (MPa) |
Tensile Strength Rm (MPa) |
Elongation A % |
Hardness Hv |
1.0 | 420 | 810 | 30 | 180 |
4.0 | 300 | 725 | 30 | 160 |
Product forms
Product | Size (mm) | Condition of Supply |
Wire | 0.2 – 12.0 | Bright Annealed Oxidized |
Bar | 5.0 – 60.0 | Hot Finished Cold Finished Peeled Bright Turned Bright Annealed |
Strip | Thickness 2.5 – 5.0 Width 20 – 100 |
Cold Finished Bright Annealed |
Ribbon | Thickness 0.2 – 1.0 Width 2.0 – 4.5 |
Bright Annealed Flat Rolled |
Stranded Wire | 2.5 – 3.0 | Hard Annealed |
Application
NiCr 70-30 is used for corrosion resistant electric heating elements in industrial furnaces with reducing atmospheres. Nickel Chrome 70/30 is highly resistant to oxidation in air. Not recommend for use in MgO sheathed heating elements, or applications using nitrogen or carburizing atmospheres.
- Electrical parts and electronic components.
- Electric heating elements (home & industrial use).
- Industrial furnaces up to 1250°C.
- Heating cables, mats and cords.