| Composed of magnetostrictive material and piezoelectric material, magnetoelectric composite film (MCF) is a kind of intelligent material which has advantages of large magnetostrictive effect and high curie temperature and it also can convert from one form to another among electric energy, magnetic energy, and mechanical energy. With the electric field or magnetic field input-controlled and output-monitored, it has sensing and actuating functions and has a promising application potential in MEMS and mechanical engineering.There are two main composite form for MCF, that is, compounding magnetoelectric films and piezoelectric films layer by layer, and either sintering magnetostrictive particles and piezoelectric particles together or bonding these two kinds of particles together with a matrix material. However, defects such as large stiffness, poor durability, and large dielectric loss lie in above two configurations of MCF, and greatly limit the application range of MCF. In this thesis, a novel 0-3 PVDF-Terfenol-D MCF is prepared and related systematically theoretical and experimental study is conducted as well, with main contents organized as follows:(1) Based on the principle of equivalent inclusion in micromechanics, a magnetostrictive constitutive model of MCF is developed with output electric displacement under different magnetic fields accounted.(2) The preparation method and polarization technics are groped. And effects of temperature, electric filed strength, etc., are explored. A series of optimum key operating conditions are found, such as concentration of solution, forming temperature, draw ratio, drawing temperature, polarization temperature.(3) Variations of dielectric constant and dielectric loss with measurement frequencies are investigated, and dielectric property is also compared between MCF and PVDF. Additionally, the effect of draw ratio on crystal structure is tested by using XRD and infrared absorption.
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