Evaluation of Nanocrystalline Materials, Amorphous Alloys and Ferrites for Repetitive-Magnetic Pulse Compression Applications

Recent advances in nanocrystalline magnetic materials and core insulation techniques are believed to be superior to the current magnetic cores that are employed as saturable switches in solid-state, repetitive magnetic pulse compressors. Accordingly, a magnetic pulse compressor test stand has been constructed at the University of Missouri-Columbia (UMC) to evaluate the switching properties of candidate magnetic materials and insulation schemes that cover the wide parameter space requisite to magnetic modulators. Experimental measurements were utilized to analyze and compare a wide variety of magnetic materials consisting of nanocrystalline cores, amorphous metal alloys and ferrites. The dependence of the insulating material and the core construction techniques, e.g., type and thickness of the insulation and ferromagnetic material were included in a model along with the magnetic core loss measurements. An advanced figure of merit was utilized to down-select the cores for a particular application based on the measurements and the UMC database. Final test results were analyzed to determine which core material had the best switching properties for a specific operational regime. The test stand, data acquisition equipment and methods, data processing, magnetic core materials under examination and final test results are discussed.