Influence of Mechanical Milling Intensity and Powder Surface Treatment on Energy Losses of Fe Compacts

The soft magnetic compacted powdered materials are used in a variety of electromagnetic applications such as electromotors, magnetic circuits of valves, cores for various inductors in computers, relays, disk drives, printers, hearing aid devices and others. These materials are used due to their relatively easy magnetization and demagnetization, maximum permeability, high magnetic saturation induction, low coercivity, low core losses. Soft magnetic compacted powder materials have high application potential based also on isotropic 3D behaviour, mechanical stability, low-cost production and they offer possibility for environmentally friendly recycling. This work focuses on the detailed description of the energy loss separation for dc and ac low frequency magnetic fields of Fe-based compacted powder. We analyzed magnetic losses of the soft magnetic materials consisting of insulated iron particles according to Bertotti’s theories. The surfaces of the iron poder particles were mechanically smoothed and the ring-shaped compacts were prepared by the high-pressure compaction. The analyze of total energy losses revealed the best magnetic properties of the material with mechanically smoothed surgaces of powder particles. Particular attention was paid to the processes of mechanical surface treatment of powder particles, coating and pressing, which have a major influence on the final properties of the materials. It is expected that optimization of these processes can significantly reduce energy losses and improve the magnetic properties of the materials.