Multiphysics computational analysis of multiferroic composite ring structures

Due to the importance of composite multiferroic structures in numerous applications including sensing, actuation, and communication, concerted analytical and experimental efforts have been afforded to these types of structures in pursuit of fundamental understanding of their behavior in the presence of different stimuli. In this study, a finite element-based Multiphysics computational framework was established to investigate a multiferroic composite ring structure consisting of an inner Terfenol-D magnetostrictive ring and an outer lead zirconate titanate (PZT) piezoelectric ring. In a precursor to the full composite investigation, the computational framework was applied to a standalone Terfenol-D magnetostrictive ring structure and was found to capture the intricacies of the interaction of the magnetic field and the geometry including magnetic shielding and shape anisotropy. When extended to the composite structure, the computational model continued to perform reasonably well in comparison to previous experimentally reported data. The forecasted converse magnetoelectric coefficient of a PZT/Terfenol-D concentric composite ring structure was found to be 357 mG/V, which is in excellent agreement with 334 mG/V experimentally reported coupling coefficient for the same geometry. Moreover, the measured and calculated mechanical strains were in reasonable agreement; given the underlying assumptions of the computational model. Future work should focus on further developing the computational model to include the nonlinear magnetostrictive and piezoelectric constitutive relationship as well as the time-dependence of the response to accelerating the development cycle of devices based on magnetoelectric composites.