Alnico alloys are composed primarly of Cobalt, Nickel, and Aluminum with the addition of Iron, Copper, and sometimes Titanium that help make them become stronger permanent magnets. They can be magnetized to produce strong magnetic fields.
Alnico magnets produce magnetic fields with strength at their poles as high as 1500 gauss, or about 3000 times the strength of the earth's magnetic field.
Alnico magnets are manufactured through a casting or sintering process.
Cast
Alnico can be processed to be intricate and complex shapes to meet customer’s demand .Some types of
Alnico are isotropic, meaning they can be efficiently magnetized in any direction. Other types, such as
Alnico 5 and
Alnico 8 are anisotropic, meaning they have a preferred direction of magnetization, orientation. Anisotropic magnets generally have a greater magnetic capacity in their preferred orientation than isotropic. Anisotropic
Alnico magnets are oriented by heating them above a critical temperature, and cooling them in the presence of a magnetic field.
Unlike casted
Alnico magnets, sintered Alnico magnets offer lower magnetic properties but better mechanical characteristics. Mixes of metal powders are pressed to shape and size, and then sintered at 2300oF in a hydrogen atmosphere. The sintering process is well suited to large volume production, and results in parts that are structurally stronger than cast magnets. Relatively close tolerances can be achieved without grinding.
1. High energies and relatively low coercivity.
2. Excellent ability to withstand extreme temperatures stability (as high as 500oC, 930oF)
3. High magnetic flux density, and resistance to demagnetization from vibration and shock.
Widely used in instruments and meters that require very stable temperature properties.
. Electronic ignition systems . Watt bour meters
. Volt-amp meters . Medical instruments
. Industrial motors . Magnetic reed switches
. Generators . Hand tools
. Vending machines
