NiCr 70/30/Cronix 70/2.4658 1250C heating wire for electric
elements
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
| NickelNi67-70% | ChromiumCr29-32% | IronFe1.0% | SiliconSi1.0-2.5% | ManganeseMn1.0% | CopperCu0.5% | CarbonC0.1% | CupperCu0.4% | AluminiumAl0.1% |
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.
