Evaluation of Magnetic-Mechanical Coupling Behavior of Multiphase Magnetostrictive Materials

An online control by the magnetic method is considered as a nondestructive evaluation approach to detect the variation of the microstructure. The magnetic model used for each phase is based on a magneto-mechanical coupling model, which is characterized, on the one hand, by the influence of applied field on the magnetic susceptibility and magnetostriction; on the other hand, it is characterized by the effect of mechanical stress on magnetization of a material. In order to predict the macroscopic behavior correctly, this model takes not only account for the multiphased state of dual-phase steels for each phase separately but also for the heterogeneity of stress and magnetic field through a self-consistent localization-homogenization scheme. The proposed multiscale approach is based on the hypothesis of domain energy balance, including the localization step, the local constitutive law application, evaluation of the volumetric fraction of martensite, and the homogenization step. Results are discussed and compared with experimental data from the literature.