Isotropic Magnets
Isotropic magnets have a random direction of magnetization throughout the material. This means that the tiny magnetic domains within the magnet are not aligned in any particular direction.
Because of the random orientation, isotropic magnets tend to be weaker than anisotropic magnets.
Alnico 2 and Alnico 3 are isotropic magnets.
Anisotropic AlNiCo Magnets
Anisotropic magnets, on the other hand, have a preferred direction of magnetization. The magnetic domains within the material are aligned in a specific direction during the manufacturing process. This alignment is achieved by applying a strong magnetic field while the magnet is being formed.
Compared to isotropic magnets (without preferential direction), there is an additional production step for anisotropic magnets. When producing the raw magnet, an electromagnetic field is applied. As a result, the material is optimally aligned. Because of that, anisotropic magnets are stronger than isotropic ones, but they can then only be fully magnetised in the predetermined direction. Due to the additional production step, anisotropic magnets are slightly more expensive than isotropic ones.
Due to the alignment, anisotropic magnets are generally stronger than isotropic magnets.They are often made from rare earth elements, such as neodymium, dysprosium, and samarium
