Magnetic materials. A review of progress

The development of the theory of ferromagnetism over the past two or three decades is briefly reviewed and some of the more outstanding relevant laboratory investigations are discussed, including work on the effect of impurities, the magnetic properties of single crystals, on hydrogen anealing and on heat-treatment in a magnetic field. The development and properties of the cold-rolled silicon steels for transformers are then reviewed, as well as advances in the hot-rolled steels. Cobalt-iron alloys with magnetic saturation values higher than for iron are discussed. Finally, the development of the nickel-iron alloys is traced, concluding with the most recent advance in this field.