Common ferromagnetic materials

This article summarizes, in tabular form, the main electrical and magnetic properties of ferromagnetic and ferrimagnetic (in the case of ferrites) materials. These materials, which are widely used in industry, have both the electrical properties of all insulating materials and solid conductors, and the specific magnetic properties for which they are actually used.

After defining the magnetic characteristics of materials and reviewing those used in practice, whether hard magnetic materials (permanent magnets) or soft magnetic materials, this article gives more general ranges of known values for a given characteristic, in the case of each material.

Methods and means of measuring characteristics are not covered in this article, and the reader is referred to other articles in the Analysis and Characterization treatise. The same applies to the applications of the materials considered (permanent materials: loudspeakers, electric motors, etc.; soft ferromagnetic materials: magnetic circuits, etc.).

Every magnetic material is characterized by a particular hysteresis cycle represented by the curve B = f (H), i.e. the magnetic induction B of the material when subjected to an external electromagnetic field H. Figure 1 shows hysteresis cycles for hard and soft magnetic materials. In the case of hard magnetic materials, the demagnetization curve, i.e. the upper left-hand quarter of the curve, gives a good representation of the properties of these materials.