Development of amorphous Fe-B based alloys for choke and inductor applications

This paper describes a method of obtaining linear permeability characteristics from Fe-B based amorphous alloys, suitable for choke and inductor applications. The properties are developed by heat treatment at temperatures above those conventionally used to develop the optimum low or high frequency magnetic properties in these alloys. Within a narrow heat treatment temperature range it is possible to develop permeabilities of between 200 and 700, linear up to high flux density levels. D.C. Energy Storage Curves are presented for Fe77.5B13Si9.5alloy, toroidal tape wound cores, heat treated in this manner. These curves indicate the potential advantages of these cores over powder cores and gapped ferrites in D.C. choke applications.