Abstract
In this thesis, composite functional materials have been studied. Composite functional materials are always composed of several substances, and combine their various advantages and disadvantages. For field-induced particles, such as calcium copper titanate (CCTO) with a huge dielectric constant and carbonyl iron (CI), nickel (Ni) and ferroferric oxide (Fe3O4) these magnetic particles, they could be easily excited or controlled by external field. As for membrane materials, usually the macromolecule, substances that are closed related to our daily life, for example, our commonly used plastic bags and plastic wrap are made by PE and PDMS often used in microuidic chips. Due to their structure and shape they have advantages of high specific strength, high insulation, high elasticity, corrosion and heat resistance, light weight and easy processing. And this thesis combine them to make different field induced nanoparticle-based membranes and explore the physical properties such as the microstructure, mechanical properties and electric/magnetic field properties of these composite functional materials, excite them through different fields, and apply their different physical properties to achieve different application scenarios. In my research, I manufactured porous CCTO-PDMS membanes to realize the ultra-sensitive wide-range small capacitive pressure sensor, as well as realizing a new type speaker using magnetic membranes as the diaphragm in a force field nonlinear coupling system, and discovering the acoustic metamaterials application using different magnetic field to control the excited patterns of magnetic membranes. It can be seen field-induced particle-based membrane is a new type material worthy of our continued exploration, which could empower many application scenarios.
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