Nichrome 80

About Nichrome 80

Nichrome 80 is a highly regarded nickel-chromium alloy, specifically composed of 80% nickel (Ni) and 20% chromium (Cr). It is the most commonly used variety of Nichrome due to its excellent balance of properties, making it ideal for a wide range of heating applications.

Available product forms: Wire, Rod, Bars, Strip, Heating Coil

Here’s a summary of its key properties and common uses:

Key Properties of Nichrome 80:

• High Electrical Resistivity: This is its most crucial feature. Nichrome 80 offers significant resistance to the flow of electricity, efficiently converting electrical energy into heat. This “Joule heating” effect is fundamental to its function as a heating element.
• Exceptional Oxidation Resistance at High Temperatures: When heated in air, Nichrome 80 forms a thin, dense, and tightly adhering layer of chromium oxide (Cr2​O3​) on its surface. This protective layer is highly stable and prevents further oxidation and corrosion of the underlying alloy, even when glowing red-hot. This is vital for its long service life.
• High Maximum Continuous Operating Temperature: Nichrome 80 can reliably operate in air at temperatures up to approximately 1177∘C (2150∘F) to 1200∘C (2192∘F).
• Good Mechanical Strength and Ductility: It retains its strength and form even at high temperatures, allowing it to be drawn into various wire gauges and shapes (like coils or ribbons) without becoming brittle or breaking.¹¹ It also maintains good ductility after extended use.
• Low Temperature Coefficient of Resistance: While its resistance does change with temperature, this change is relatively small and predictable, leading to consistent heating performance over its operating range.
• Good Corrosion Resistance: In general, it resists corrosion in various environments, though it can be susceptible to sulfur-containing atmospheres.

Physical Properties (Approximate Values):

• Melting Point: Approximately ²⁴1400∘C (²⁵2552∘F).
• Density: Around 8.31 g/cm3 to 8.41 g/cm3.
• Tensile Strength (annealed): Typically around 650 MPa to 800 MPa or more, depending on the form and temper.
• Elongation: Generally >20% (indicating good ductility).
• Coefficient of Thermal Expansion (20-1000∘C): Approximately 17×10−6/∘C to 18×10−6/∘C.
• Specific Heat Capacity: Around 0.44 kJ/kg⋅K at 20∘C.
• Thermal Conductivity: Approximately 11.3 W/m⋅K to 15 W/m⋅K at 20∘C.

Common Uses of Nichrome 80:

Due to these properties, Nichrome 80 is extensively used in applications where controlled heating and high-temperature stability are required:

• Heating Elements: This is its primary and most widespread application.¹⁹ You’ll find Nichrome 80 in:
  • Household Appliances: Toasters, hair dryers, electric ovens, electric kettles, soldering irons, electric blankets, water heaters, and more.
  • Industrial Furnaces: As heating elements in various types of industrial heating equipment.
  • Heat Guns: For tasks like stripping paint or shrinking tubing.
  • Electric Space Heaters and Baseboard Heaters.
• Hot Wire Cutters: For precise cutting of materials like foam, plastics, and rubber due to its ability to heat up quickly and cleanly slice through the material.
• Electronic Cigarette/Vape Coils: Its rapid heating response and stability make it a popular choice for vaporizing e-liquids.²⁴
• Laboratory Equipment: Used for flame testing (to identify elements by their characteristic flame color) and in various heating devices requiring precise temperature control.
• Explosives and Pyrotechnics: As a bridge wire in electric ignition systems for fireworks and model rocket igniters.
• Ceramics and Glassmaking: Used as an internal support structure for clay sculptures during firing in kilns because it can withstand the extreme temperatures without deforming.
• Resistors: In various electrical circuits where stable resistance at elevated temperatures is needed.

Nichrome 80’s combination of high electrical resistance, excellent high-temperature oxidation resistance, and good mechanical properties makes it an indispensable material for countless heating and thermal processing applications across consumer and industrial sectors.