Insights into the displacement field in magnetoelectric composites

The performance of strain-mediated magnetoelectric composite multiferroics hinges on the interface condition in both direct and converse coupling paradigms. The objective of this article is to report experimentally validated computational models of composite cylinder structure consisting of an outer piezoelectric cylinder mechanically attached to an inner magnetostrictive layer. Three contact conditions were computationally investigated, including bonding, no separation, and standard definitions from the used finite element package. The simulations were used to extract the harmonic, modal, and transient responses of the composite cylinder structure, which were compared to experimental work. Under the influence of an AC electric field, the in-plane and out-of-plane displacement maps were simultaneously measured using a noncontact interferometric technique. Results from the harmonic analysis were used to tune the material properties and boundary conditions used in all subsequent simulations, whereas the resonance frequency was in excellent agreement with the experiment. The modal analysis was validated by comparing a subset of the experimental and computational vibrational modes. Finally, the transient analysis was found to be in reasonable agreement with the experimental results with a focus on the response at the excitation frequency. The validated analysis framework can be used in the development of sensors and actuators based on composite multiferroics cylinder structures.