Nichrome

From Wikipedia, the free encyclopedia

Nichrome is a brand name for nickel-chromium resistance wire, a non-magnetic alloy of nickel and chromium. A common alloy is 80% nickel and 20% chromium, but there are many others to accommodate various applications or lower cost. It is silvery-grey in colour, is corrosion resistant, and has a high melting point of about 1400 °C. Due to its relatively high resistivity and resistance to oxidation at high temperatures, it is widely used in heating elements, such as in hair dryers, electric ovens and toasters. Typically, Nichrome is wound in wire coils to a certain electrical resistance, and current passed through to produce heat.

Nichrome is used in the explosives and fireworks industry as a reliable ignition system, such as electric matches and model rocket igniters.

The alloy tends to be expensive due to its high chromium content. Distributor pricing is typically indexed to commodity market prices for chromium.

Another area of usage is motorcycle silencers.

[edit] Table of properties for Nichrome

The properties of Nichrome vary depending on its alloy. Figures given are representative of typical material.

Material property Value Units
Modulus of elasticity 2.2 × 1011 Pa
Specific gravity 8.4 None
Density 8400 kg/m3
Melting point 1400 °C
Electrical resistivity at room temperature 1.1 × 10-6[1] Ω·m
Specific heat 450 J/kg°C
Thermal conductivity 11.3 W/m/°C
Thermal expansion 4 × 10-6 m/m/°C
Standard ambient temperature and pressure
used unless otherwise noted.
  1. ^ http://www.goodfellow.com/csp/active/gfMaterialInfo.csp?MATID=NI05