Alnico is a type of alloy commonly used to create permanent magnets for use in industry. The name is derived from its primary components: Aluminium, Nickel and Cobalt. It is one of the older alloys in use and contains relatively common elements and is, as such, generally cheaper to use than other, more exotic magnetic alloys. This, in conjunction with Alnico's relative resistance to temperature induced magnetic field fluctuation or degradation, means that it is commonly used throughout industry in sensors, loudspeakers, magnetos, motors, meters, holding devices and any other device applications where a cheap, mechanically strong and resilient permanent magnet is required.
Several grades of this material are available, tailored to both magnetic output, mechanical strength and heat resistance required for that application.
Lower grades of this material exhibit unoriented or isotropic structure, resulting in relatively low magnetic output. Higher grades have an anisotropic structure and have a higher magnetic output, though only along a single axis.
Magnets made using this alloy may be either cast or sintered. Cast Alnico can be made into intricate shapes that may not be possible with other materials.
Sintered Alnico, while slightly weaker than cast material, exhibits superior mechanical characteristics. This type of magnet is manufactured using a powder metallurgy process which uses controlled atmosphere, high temperature sintering to produce near net shape parts.
Alnico material can be easily demagnetized due to its low coercive force and must therefore be handled properly.