So, what is nichrome made of? Nichrome wire is constructed from an alloy made from nickel (Ni), chromium (Cr), and often iron, primarily it is used as a resistance wire.
Typical composition:
NiCrA – Ni (80%) and Cr (20%) or
NiCrC – Ni (60%) and Cr (15%) and Fe (25%)
Ideally suited as a resistance wire heating alloy due to its high electrical resistivity, high melting point and resistance to high temperature oxidation (as a result of forming a protective layer of chromium oxide which makes it highly stable in air at high temperature) it was patented (as Chromel) around 1906 as a result of the collaboration between metallurgist Albert Leroy Marsh and his then employer William Hoskins of the Hoskins Manufacturing Company. The alloy, historically, and still today is generally marketed as Nichrome.
By far the most common use of Nichrome is when wound in coils and used as a heating element in electrical appliances like cookers, toasters, kilns and electric fires although it does have a number of specialist uses:
- The fireworks and explosives industry often use Nichrome as an electrical ignition systems where it forms the bridge wire.
- For ‘hot wire’ foam/polystyrene cutting applications.
- As the positive electrode in thermocouples. Generally nichrome/alumel or nichrome/constantan which can be used to monitor temperatures up to 1110 °C
- As a support structure for clay products whilst being fired.
- More recently, nichrome has become popular for use in electronic cigarettes (e-cig or e-cigarette), personal vaporizer (PV) or electronic nicotine delivery system (ENDS) as an alternative to Kanthal