Strong AlNiCo Multi Pole Rotor Magnet
Most Alnico magnets are manufactured using typical foundry casting techniques, where the molten alloy is poured into sand molds. Very small magnets, usually one ounce or less, are produced using press and sinter techniques. Sintered Alnico magnets have features that make them particularly effective in very small precision devices. Sintering magnets with small holes and intricate shapes is possible.
Physical Properties of Cast Alnico
Curie Temperature (℃)
Max. Operating Temperature (℃)
Relative Recoil Permeability (μrec)
Saturation Field Strength (kOe, kA/m)
Temperature Coefficient of Br (%/℃)
-0.025 ~ -0.02
Temperature Coefficient of iHc (%/℃)
+0.01 ~ +0.03
Strong AlNiCo Rotor Magnet
Sintered magnets are available in both isotropic and anisotropic form, with a broad range of unit properties. Their magnetic properties are similar but often slightly lower than cast magnets of equivalent grade.
Alnico magnets, cast and sintered, are finished ground using abrasive grinding to produce the final shape and tolerance. Once ground the material is a shiny metallic finish. These materials are brittle and cannot be machined or drilled.
Q1: How permanent is the strength of a magnet?
A1: If a magnet is stored away from power lines, other magnets, high temperatures and other factors that adversely affect the magnet, it will retain its magnetism essentially forever.
Q2: What might affect the strength of a magnet?
A2: Heat/Radiation/Strong electrical currents in close proximity/Other magnets in close proximity to the magnet/Neo magnets will corrode in high humidity environments unless they have a protective coating.
Q3: Can a magnet that has lost its magnetism be re-magnetized?
A3: Provided that the material has not been damaged by extreme heat, the magnet can be re-magnetized back to its original strength.