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Introduction to
AlNiCo Magnets |
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AlNiCo magnets, are made up of a
composite of aluminum, nickel and cobalt with small amounts of other
elements, have good temperature stability, good resistance to
demagnetization, high residual induction, and relatively high
energies. By strength, they are much weaker than NdFeB magnets, SmCo
magnets and Ferrite magnets.
Alnico magnets are manufactured by using primarily two processes:
1. Cast alnico magnets that are made by pouring melted alnico into a mold. The solidified material is rough ground and then heat treated and cooled. The material is either anisotropic (treated in a magnetic field) or isotropic (treated outside a magnetic field). After treatment the material is ground to specific tolerances and magnetized.
2. Sintered alnico magnets are made from a powdered mixture of ingredients that are pressed into a die under tons of pressure. They are then sintered in a hydrogen atmosphere and cooled in an anisotropic or isotropic environment.
Alnico magnets are commonly used in applications such as instruments and meters that require very stable temperature properties. Electronic ignition systems, generators, vending machines, hand tools, magnetic reed switches, volt-amp meters and medical instruments are some of the commonly used applications of alnico magnets. |
