EXPRESS METHOD OF COMPARATIVE ASSESSMENT OF LOSSES IN SOFT FERROMAGNETIC MATERIALS

Magnetic materials play an important role in many fields of science and technology. They are used for the manufacturing of magnetic conductors, transformers, relay cores, amplifiers, etc. The use of pure iron in electrical engineering is due to its high saturation magnetization, satisfactory magnetic permeability, and low coercive force. From an economic point of view, this is a cheap magnetic material. However, to achieve high indicators of magnetic properties, a high degree of purity and a homogeneous structure of the metal, which excludes crystal lattice defects are necessary. Application of powder metallurgy methods made it possible not only to create new types of magnetic materials, but also to eliminate such disadvantages of cast materials as shrink cavity and coarse-grained structure. They also make it possible to prepare magnetic materials with a given chemical composition and structure. At the same time, a significant saving of material is achieved, which reduces its resistance by 30–60 % compared to cast analogues. The paper proposes a method of express analysis of the quality of a ferromagnetic material operating in alternating magnetic field. The method is based on a comparative assessment of the electrical energy consumed by a coil with a magnetic conductor containing a sample of the material under study. An example of the use of the proposed method for studying the effect of an additive to the iron powder in the capsulator (organosilicon varnish was used) on the active power consumed by the coil is given. The determined optimal content of the capsulator in the iron powder, which corresponds to the minimum power losses on the coil with the magnetic conductor, was about 0.9 % by mass. Bibl. 18, Fig. 3.