Grant Jesse, Wang Yiming, Roth Alexander, Liu Yangfan, Rahimi Rahim, Song Guochenhao, Cakmak Mukerrem
School of Materials Engineering, Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, United States.
School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907, United States.
ACS Appl Mater Interfaces. 2024 Nov 6;16(44):60749-60761. doi: 10.1021/acsami.4c10260. Epub 2024 Oct 24.
Highly anisotropic piezoelectric composites promise to progress electroacoustic devices as a class by combining the advantages of both piezoceramics and polymers. Fundamentally, piezoelectric loudspeakers employ the converse piezoelectric effect to convert electrical to mechanical energy. Quasi-1-3 piezoceramic/polymer composites enable flat-panel loudspeakers that are tunable in elastic modulus, with opportunities for mechanical flexibility, optical transparency, and large-area coverage. Their processing route enables relatively flexible design parameters, such as the particle loading, polymer-matrix modulus, film thickness, film size, and electrode-material stiffness. Alternative processing routes of electric field (E-field) aligned-piezoelectric composites are demonstrated, including using the relaxor ferroelectric lead magnesium niobate-lead titanate (PMN-PT) to enhance the acoustic performance and photocurable resins to accelerate the materials processing. Material properties critical for dielectrophoresis are characterized, and loudspeakers were fabricated based on the optimal processing conditions. Subsequently, electroacoustic characterization explores the effect of loudspeaker size, substrate stiffness, the microphone distance, the piezoceramic material, and the matrix modulus. Finally, finite-element (FE) modeling of the electromechanical behavior validates the natural frequencies and modes shapes of the loudspeakers via the analytical solution and frequency response to electrical and mechanical excitation. Good correspondence between the predicted electroacoustic performance and experimentally validated model is observed.
高度各向异性的压电复合材料有望通过结合压电陶瓷和聚合物的优点，推动电声器件作为一类产品取得进展。从根本上讲，压电扬声器利用逆压电效应将电能转换为机械能。准1-3型压电陶瓷/聚合物复合材料可实现弹性模量可调的平板扬声器，具有机械柔韧性、光学透明性和大面积覆盖的潜力。其加工路线允许采用相对灵活的设计参数，如颗粒负载量、聚合物基体模量、薄膜厚度、薄膜尺寸和电极材料刚度。展示了电场（E场）取向压电复合材料的替代加工路线，包括使用弛豫铁电体铌镁酸铅-钛酸铅（PMN-PT）来提高声学性能，以及使用光固化树脂来加速材料加工。对介电泳至关重要的材料特性进行了表征，并基于最佳加工条件制造了扬声器。随后，电声表征研究了扬声器尺寸、基板刚度、麦克风距离、压电陶瓷材料和基体模量的影响。最后，通过解析解以及对电激励和机械激励的频率响应，对机电行为进行有限元（FE）建模，验证了扬声器的固有频率和振型。观察到预测的电声性能与经过实验验证的模型之间具有良好的一致性。
