文献类型：期刊文献

英文题名：Fabrication and characterization of EMFi-Based Air-Coupled Ultrasonic Transducers

作者：Tong, Likun[1]; Zhu, Wujun[1]; Xiang, Yanxun[1]; Deng, Mingxi[2]; Pan, Jing[3]; Chen, Yingna[3]; Cheng, Qian[3]

机构：[1] School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai, 200237, China; [2] Logistics Engineering University, Chongqing, China; [3] Tongji University, Shanghai, 200092, China

年份：2017

卷号：32

期号：1

外文期刊名：Proceedings of Meetings on Acoustics

收录：EI(收录号：20182005200343)

语种：英文

外文关键词：Interferometers - Ultrasonic transducers - Fabrication - Laser interferometry - Polypropylenes

摘要：In this work, we developed, fabricated and characterized planar and spherically focused air-coupled ultrasonic transducers based on electromechanical film (EMFi) system, which contains two-sided Al electrodes and cellular polypropylene (cPP) ferroelectret films. Three devices have been fabricated and tested. The planar one has a 20 mm aperture. And one of the spherically focused transducers has a 20 mm aperture, 35 mm focus, another with a 30 mm aperture, 40 mm focus. These transducers have been characterized with a series of experiments. The bandwidth and resonance frequency of operation as transmitters were obtained using laser interferometer. As receiver, the pulse-echo frequency response in acoustic experiments can be compared with results of the interferometer test. Finally, the focused one with 20 mm diameter was selected to get scanning images of the polyethylene step wedge with a series of different diameter holes in pulse-echo mode. ? 2018 Acoustical Society of America.