Excellent temperature stability, high residual induction and relatively high energy characterises the Alnico materials, which are composed primarily of alloys of Aluminium, Nickel, and Cobalt. They are manufactured through either a casting or sintering process. Cast magnets may be manufactured in complex shapes, such as horseshoes etc. Sintered Alnico offer slightly lower magnetic properties but better mechanical characteristics than cast Alnico.

Cast Alnico 5 is the most commonly used of all the cast Alnico magnets. This material is used extensively in rotating machinery, meters, instruments, sensing devices, and holding applications, to name but a few.

Alnico is hard and brittle and cannot be machined or drilled.  Holes are usually cored in at the foundry, and magnets are cast close to final size and then finished by grinding to close tolerances.

Alnico has a low coercive force, and is easily demagnetized if not handled with care.  For optimum performance of Alnico 5, the magnetic length should be approximately 5 times the pole diameter or equivalent diameter.  For example, a 0.250" diameter magnet should be about 1.00" long.

Because of its higher coercivity, Alnico 8 may be used in shorter lengths and in disc shapes.