Nonlinear modeling of bending-mode magnetoelectric coupling in asymmetric composite structures with magnetization-graded ferromagnetic materials

The bending-mode magnetoelectric (ME) coupling in the asymmetric laminate composite with a magnetization-graded ferromagnetic material has been investigated in this paper. Based on the nonlinear constitutive relationships of the magnetostrictive material, the dynamic piezomagnetic models have been presented for magnetostrictive materials after considering the remanence, demagnetization, and flux concentration effects. In addition, the bending-mode resonant ME coupling model is developed based on the proposed dynamic piezomagnetic model, the motion equation of the ME composite, and the ME equivalent circuit method. The composite structures FeCuNbSiB/Ni/PZT with negative magnetostrictive Ni and FeCuNbSiB/FeNi/PZT with positive magnetostrictive FeNi have been used to confirm the validity and reliability of the theoretical model. The theoretical results show that the bending-resonant ME coefficients reasonably agree with the experimental results. This theoretical model is of importance for understanding the bending-mode ME response of the asymmetric structure with magnetization-graded ferromagnetic materials and designing the ME devices.