This article provides a comparison of Magnetics powder and ferrite cores when used in inductors, including small and large DC inductors and large AC inductors.
These results clearly show a minimum in the core losses, for both high and low frequencies in both lubrication systems, with around 30-40 wt% FeSi added in the mixture, indicating that this addition renders the optimum composition for this material.
Molding power inductors are made by the uniaxial compaction of a mixture of magnetic alloy powder and organic resin. Internal strain in magnetic powders is generated by high molding compaction, resulting in decreased permeability, coercivity, and saturation magnetization [ 13 ].
[ Google Scholar] Hsiang, H.I.; Chuang, K.H.; Lee, W.H. FeSiCr alloy powder to carbonyl iron powder mixing ratio effects on the magnetic properties of the iron-based alloy powder cores prepared using screen printing.
Compared to pure Fe-6.5% Si, the advantages of this new material arehigher magnetic saturation and high component density similar to that of pure Somaloy 110i 5P, as well as easy manufacturing procedures, i.e., the compaction pressure is low or moderate (800-1200 MPa vs. 1200-2000 MPa for pure FeSi) which reduces production costs.
Power inductors require the presence of an air gap within the core structure. The purpose of the gap is to store the energy, and to prevent the core from saturating under load. Another way to express the function of the air gap is to say that it reduces and controls the effective permeability of the magnetic structure.