Cr30Ni70 Nickel-Chromium Resistance Wire
Also Known As: Nikrothal 70, Chromel 70/30, N7, Hytemco, HAI-NiCr 70, Balco, Tophet 30, Resistohm 70, Cronix 70, Stablohm 710,70/30 Nichrome, NiCr70/30
Max. 1250°C| Chemical Composition (%) | |
|---|---|
| Element | Value |
| C | ≤0.08 |
| P | ≤0.02 |
| S | ≤0.015 |
| Mn | ≤0.6 |
| Si | 0.75~1.6 |
| Cr | 28.0~31.0 |
| Ni | Remainder |
| Al | ≤0.5 |
| Fe | ≤1.0 |
| Physical Properties | |
| Max. Operating Temp. | 1250°C |
| Resistivity at 20°C (μΩ·m) | <0.50mm: 1.18±0.05; ≥0.50mm: 1.20±0.05 |
| Density | 8.10 g/cm³ |
| Thermal Conductivity (20°C) | 14 W/(m·K) |
| Linear Expansion Coeff. (20–1000°C) | 17.0×10-6/K |
| Specific Heat Capacity | 0.46 J/(g·K) |
| Approx. Melting Point | 1380°C |
| Elongation (A/%) | ≤3.0mm: ≥20%; >3.0mm: ≥25% |
| Tensile Strength (Rm) | ≥650 MPa |
| Accelerated Life Test | ≥50h/1250°C |
| Microstructure | Austenite |
| Magnetic Properties | Nonmagnetic |
| Available Forms | |
| Form | Size |
| Bright & Soft Annealed Wire | 0.025–1.6mm |
| Acid-Pickled Wire | 1.0–12.0mm |
| Rods | 6.0–150.0mm |
| Flat Wires | Width 0.2–6.0mm, Thickness 0.08–1.0mm |
| Strips | Width 5.0–300mm, Thickness 0.05–4.0mm |
Product Overview
Cr30Ni70 is a high-performance nickel-chromium resistance alloy with increased chromium content compared to Cr20Ni80. The higher chromium proportion delivers enhanced oxidation resistance, making it ideal for demanding high-temperature environments where extended service life is critical. It is widely used in industrial furnaces, heat treatment equipment, and high-temperature processing applications.
Key Advantages
- Superior oxidation resistance at temperatures up to 1250°C
- Higher chromium content for improved surface oxide layer stability
- Excellent long-term creep strength at elevated temperatures
- Reliable performance in oxidizing atmospheres
Typical Applications
- High-temperature industrial furnace elements
- Heat treatment equipment and annealing furnaces
- Ceramic kiln heating elements
- Glass processing and tempering equipment
- Semiconductor manufacturing heating systems
Standards & Compliance
GB/T 1234-2012
High Resistance Alloys
DIN 17471
Resistance Heating Alloys (German Standard)
ASTM B344
Nickel-Chromium and Nickel-Chromium-Iron Alloys for Electrical Heating Elements (US Standard)
ASTM B603
Iron-Chromium-Aluminum Alloys for Electrical Heating Elements (US Standard)
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