IEE Colloquium on New Magnetic Materials - Bonded Iron, Lamination Steels, Sintered Iron and Permanent Magnets (Digest No.1998/259)

Bonded iron, also known as composite iron, is an improved technology initially used in car ignition coils. It is now being considered for use in rotating machines. Whereas laminations limit AC flux to 2 dimensions, bonded iron being isotropic allows flux in 3 dimensions. New machine topologies are therefore possible. These materials have lower permeability but benefit from lower losses at higher frequencies. Comparison with the latest improvements in lamination steels are therefore also covered. New high density sintered iron materials for DC magnetic circuits also offer improved properties. The colloquium covers these topics and also developments in rare earth permanent magnet materials, bonded and fully dense