Components of the core losses under low frequency magnetic field of the bulk Ni–Fe compacted powder material

Permalloy is the name of nickel–iron alloys, which after heat treatment have an initial permeability much larger than that one of pure iron and are produced usually in the form of thin sheet. Therefore it is logical to attempt to prepare such material in more “bulk” form, for example in the form of a cylinder or a ring, which would be more convenient for some industrial applications. The aim of this work was to investigate the influence of the powder size on ac and dc magnetic properties of the bulk samples prepared by a hot compaction of the powder. By analysis of the contributions of the hysteresis losses, the eddy current losses and the anomalous losses to the core losses we obtained that the fraction of all contributions strongly depends on the particle size of the powder used for preparation of the bulk material.

► Permalloy NiFe prepared by compaction exhibit very good soft magnetic properties.
► The role of the anomalous loss was confirmed to be very important in the core loss.
► The lowest value of losses exhibits the sample consisting of the largest particle.