Aperam Resistohm 70 Resistant Alloys-Nickel Chromium Alloys，1

### **Product Introduction: Aperam Resistohm® 70 - Nickel-Chromium Resistance Alloy** **Overview** Aperam Resistohm® 70 is a high-performance nickel-chromium electrical resistance alloy designed for medium to high-temperature heating applications. This alloy offers an optimal balance of electrical resistance, oxidation resistance, and mechanical properties, making it suitable for continuous operation at temperatures up to 1150°C (2100°F). With its reliable performance and cost-effectiveness, Resistohm 70 serves as an excellent choice for various industrial and commercial heating applications. --- #### **Chemical Composition (Typical % by Weight)** | Element | Content (%) | Role & Benefit | |---------|-------------|---------------| | **Nickel (Ni)** | 58.0 - 62.0 | Matrix element providing base resistivity and high-temperature stability | | **Chromium (Cr)** | 28.0 - 31.0 | Enhances oxidation resistance and forms protective chromium oxide layer | | **Iron (Fe)** | ≤ 3.0 | Controlled for cost optimization and mechanical properties | | **Silicon (Si)** | 0.50 - 1.50 | Improves oxidation resistance and scale adhesion | | **Manganese (Mn)** | ≤ 1.50 | Enhances hot workability and manufacturability | | **Carbon (C)** | ≤ 0.15 | Controlled for high-temperature performance | | **Aluminum (Al)** | ≤ 0.50 | Contributes to oxidation resistance | | **Copper (Cu)** | ≤ 0.50 | Residual element control | | **Sulfur (S)** | ≤ 0.015 | Minimized to prevent hot shortness | *Note: Resistohm is a registered trademark of Aperam. This alloy corresponds to NiCr 70/30 resistance heating alloy.* --- #### **Physical & Mechanical Properties** **Physical Properties:** - Density: 8.20 g/cm³ (0.296 lb/in³) - Melting Range: 1380-1420°C (2516-2588°F) - Thermal Expansion: 14.0 μm/m·°C @ 20-1000°C - Thermal Conductivity: 14.5 W/m·K @ 20°C - Specific Heat Capacity: 450 J/kg·K @ 20°C - Electrical Resistivity: 1.10 μΩ·m at 20°C **Mechanical Properties (Room Temperature):** - Tensile Strength: 750-900 MPa (109-131 ksi) - Yield Strength (0.2% Offset): 400-550 MPa (58-80 ksi) - Elongation: 25-40% - Hardness: HV 170-210 **High-Temperature Characteristics:** - Maximum Operating Temperature: 1150°C (2100°F) - Good resistance to thermal cycling - Stable electrical resistance characteristics - Moderate high-temperature strength --- #### **International Standards and Specifications** - **IEC 60240:** Dimensions and technical requirements for electric heating elements - **ASTM B344:** Electrical Heating Element Alloys - **DIN 17470:** Electrical resistance alloys - Technical delivery conditions - **EN 10095:** Heat resisting steels and nickel alloys - **JIS C2520:** Nickel-chromium and nickel-chromium-iron alloys for electrical heating - **GB/T 1234:** Chinese standard for high resistance alloys - **UL Standard 1030:** Heating, Cooling, and Fan-Grid Heating Elements --- #### **Product Applications** **Industrial Heating Systems:** - Industrial furnace heating elements - Heat treatment equipment - Ceramic and pottery kilns - Aluminum melting furnaces - Laboratory and research furnaces **Commercial and Domestic Appliances:** - Electric oven and range elements - Industrial toasters and food service equipment - Water heater elements - Space heating appliances - Hair care and beauty appliances **Specialized Electrical Applications:** - Power resistors and rheostats - Current limiting devices - Temperature control systems - Electrical heating cables - Automotive heating components --- #### **Key Advantages** 1. **Good Oxidation Resistance**: Reliable performance in air at temperatures up to 1150°C 2. **Stable Electrical Characteristics**: Consistent resistivity over extended service life 3. **Cost-Effective Performance**: Optimal balance of performance and cost 4. **Good Thermal Cycling Resistance**: Withstands repeated heating and cooling cycles 5. **Adequate High-Temperature Strength**: Maintains structural integrity at operating temperatures 6. **Excellent Formability**: Easy to coil, bend, and shape for various heating element designs 7. **Proven Reliability**: Established track record in diverse heating applications 8. **Wide Operating Range**: Suitable for both medium and high-temperature applications --- **Conclusion** Aperam Resistohm® 70 represents a reliable and cost-effective nickel-chromium resistance heating alloy that delivers consistent performance in medium to high-temperature electrical heating applications. Its well-balanced chemical composition ensures good oxidation resistance, stable electrical properties, and adequate mechanical strength, making it suitable for a wide range of industrial, commercial, and domestic heating applications. Supported by international standards and comprehensive quality assurance, Resistohm 70 provides an economical yet reliable solution for heating element manufacturers seeking optimal performance and durability in their products. The alloy's versatility and proven service history make it a preferred choice for diverse heating applications where consistent thermal performance and long service life are essential requirements.

Packing of Standard Packing: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 3427 gallon liquid totes Special package is available on request.