Enhancement of permeability of Co-based amorphous alloy by two-step cooling method

Abstract The soft magnetic properties of Co-based amorphous alloy have been investigated as a function of cooling condition followed by high-temperature annealing. Furnace cooling to the Curie temperature and subsequent water quenching (F&W method) considerably increased the initial permeability by 60% and 100% higher than those of the furnace-cooled and water-quenched samples, respectively. The F&W sample also showed superior high-frequency characteristics. This phenomenon was analyzed in terms of internal thermal strees and the magnetic ordering. We confirmed the alloy annealed by F&W shows better shielding effectiveness