Application of Electroless-Plated Magnetic Coating to Reduce Core Loss of Electrical Steel

A possibility to reduce core loss in non-oriented (NO) electrical steel by applying magnetic coating has been investigated. This technique involves electroless plating of magnetic coating onto the surface of electrical steel. The material system was NiCoP coatings with different thicknesses (1, 5, and 10 ?m) deposited onto the surface of commercially available Fe-3%Si NO electrical steel. Characterization of deposited NiCoP coating was carried out using X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive X-ray (EDX) spectrometer. The deposited Ni-Co-P coatings were amorphous/nanocrystalline and composed of 56-59% Ni, 32-35% Co and 8-10% P by mass. Effect of coatings on core loss of the electrical steel was determined using a single sheet test. A core loss reduction was achieved with the NiCoP coating with a thickness of 1 ?m magnetized at a magnetic flux density of 0.3T.