Experimental Verification of a Simulation Model for Partial Demagnetization of Permanent Magnets

This paper aims to verify a finite element method simulation model for demagnetization of permanent magnets (PMs). The model is designed to determine the remaining magnetization within the PM after it has been exposed to high demagnetizing fields and/or temperature. An experimental setup was built and a PM of SmCo type was experimentally tested. Good agreement is shown between the simulation and experimental results. A maximal deviation of 3% of the simulation results in relative to the experimental results were achieved for most part of the magnet. During the calibration of the simulation model, it was found that the coercivity had to be significantly more negative compared with the PMs reference value to match simulation results to the experimental results.

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