Alnico Magnets

Alnico Magnets are produced by casting or sintering processes.Anisotropic alnico magnets are oriented by heating above a critical temperature, and cooling in the presence of a magnetic field. Both isotropic and anisotropic alnico require proper heat treatment to develop optimum magnetic properties — without it alnico's coercivity is about 10 Oe, comparable to technical iron, which is a soft magnetic material. After the heat treatment alnico becomes a composite material, named "precipitation material"—it consists of iron and cobalt rich precipitates in rich-NiAl matrix.
  Alnico Magnets www.htma*** are widely used in industrial and consumer applications where strong permanent magnets are needed; examples are electric motors, electric guitar pickups, microphones, sensors, loudspeakers, traveling-wave tubes, and cow magnets. In many applications they are being superseded by rare earth magnets, whose stronger fields (Br) and larger energy products (BHmax) allow smaller size magnets to be used for a given application.Alnico's anisotropy is oriented along the desired magnetic axis by applying an external magnetic field to it during the precipitate particle nucleation, which occurs when cooling from 900 °C (1,650 °F) to 800 °C (1,470 °F), near the Curie point.