Grain boundary engineering of power inductor cores for MHz applications

In this article we present the latest trends in processing, composition, theory, and utility of spinel ferrites for use as power inductor cores for a wide range of applications including power generation, conversion, and conditioning at MHz frequencies. Furthermore, it is a principle goal of this article to examine state of the art approaches and innovative methodologies to engineer grain boundary regions in composition, structure, and electrical and magnetic properties that allow spinel ferrites to operate at frequencies well above the state of technology (i.e., f > 1 MHz) with low core power loss while concomitantly maintaining high efficiency, high permeability and saturation induction.