Efficient Deperming Protocols Based on the Magnetic Properties in Demagnetization Process

Recently developed magnetic materials have high coercive force and high squareness ratios to meet the industrial demand. In the electric and electronics industries and in defense development, a deperming procedure is needed to reduce residual magnetization to zero. But the conventional deperming has a limitation of not considering the magnetic hysteresis. To research an efficient and reliable deperming current, this paper proposes a deperming analysis process using the Preisach modeling combined with the finite-elements method, which is verified by magnetic treatment facility experiments. By analyzing the trace on the Preisach plane, flash-D deperm, which leaves a lot of trace remaining on the high-density coercive force, was found to be more effective. Therefore, a method to formulate a flash-D deperm current using Preisach modeling is proposed. Finally, it is expected to obtain the most efficient flash-D deperm current according to the magnetic hysteresis of each ferromagnetic material.