Application of an extended hysteresis model to quantitative evaluation of surface-modified magnetic materials

In this study, we developed a model-based approach for determining case depths of surface hardened steels from hysteresis data. A magnetic hysteresis model was extended to simulate the observed two-stage magnetization reversal process which took place in the core and case regions of hardened samples under different applied fields. Case depths were estimated by modeling the hysteresis loop as a weighed sum of signals from the case and the core. The results were found to agree with the values measured from the hardness depth profiles.