Cunife is analloy ofcopper (Cu),nickel (Ni),iron (Fe), and in some casescobalt (Co). The alloy has the same linearcoefficient of expansion as certain types of glass, and thus makes an ideal material for the lead out wires in light bulbs andthermionic valves.Fernico exhibits a similar property. It is amagnetic alloy and can be used for makingmagnets.
Cunife has a magneticcoercivity of several hundredoersteds. Unlike most high coercivity magnetic materials which are hard and brittle and need to becast into shape, cunife can bedrawn into thin wires. Wires as thin as fivethou can be produced this way.[1] Thicker rods of the material can bethreaded which is also something that is not possible with the more commonly used magnetic materials.[2]
In the early 1970s,Fender Musical Instruments Corporation used Cunife magnets in theirWide Rangehumbuckerpickups, however they discontinued use, due to Cunife being hard to source. Fender began producing cunife pickups again in 2020.[3]
Given in weight %
| Cu | Ni | Fe | Co | |
|---|---|---|---|---|
| Cunife 1 | 60% | 20% | 20% | - |
| Cunife 2 | 60% | 20% | 17.5% | 2.5% |