The traditional [0/90]T laminate has two stable equilibrium shapes, and it is possible to go from one shape to the other by means of an external force. In the past, researchers have attempted to obtain the snap-through between the two equilibrium states using smart actuators like shape memory alloy (SMA) wires and macro-fiber composite (MFC) patches. The integration of these actuators adds several complications. Moreover these smart actuators are generally attached to the surface of the laminate hence influencing the structural performance substantially. Recently, non contact magnetic actuation was experimentally demonstrated to be a viable method of reversible snap-through. A non-contact actuation using magnetic fields provides an elegant means of achieving reversible snapping without affecting the bistability characteristics of the laminate. In this work, a numerical model has been developed to aid the design of non-contact systems comprising of a ferromagnetic material actuated by a solenoid. The developed model uses a Rayleigh-Ritz based potential minimization to capture the magnetic snap-through of a hybrid [Fe/0/90/Fe]T laminate. The model accurately captures the bistability of the multi-sectioned hybrid layup and can be used for the design of coils to provide the necessary actuation currents.
Magnetoelectric (ME) materials have presented themselves appealing towards sensing and energy harvesting applications. Comprehensive studies under linear and nonlinear material behavior have been performed on symmetric ME laminates subjected to homogeneous deformations. However, studies on unsymmetric laminates working under bending action are sparse, despite their advantages like low resonant frequencies. A finite element (FE) model is thus developed in this work based on Mindlin plate theory to quantify the ME coupling under an applied magnetic loading in quasi-static and resonant conditions. Due emphasis has been given to the material nonlinearity of the ferromagnetic phase and the resulting ME coupling in bending and axial as well as torsional modes has been studied. The influence of the frequency of applied AC magnetic field, the magnitude of the bias field and their orientation relative to the plate axes and the effect of plate width are explored for free-free and cantilever conditions. The developed model is also validated against data available in literature. The results illustrate that the cantilever configuration offers a two-fold advantage of high ME coupling and low resonant frequency.