Broadband and high sensitive time-of-flight diffraction ultrasonic transducers based on PMNT/epoxy 1-3 piezoelectric composite

Dongxu Liu; Qingwen Yue; Ji Deng; Di Lin; Xiaobing Li; Wenning Di; Xi'an Wang; Xiangyong Zhao; Haosu Luo

doi:10.3390/s150306807

Broadband and high sensitive time-of-flight diffraction ultrasonic transducers based on PMNT/epoxy 1-3 piezoelectric composite

Sensors (Basel). 2015 Mar 19;15(3):6807-17. doi: 10.3390/s150306807.

Authors

Dongxu Liu^{1

2}, Qingwen Yue^{3

4}, Ji Deng^{5

6}, Di Lin¹, Xiaobing Li⁷, Wenning Di⁸, Xi'an Wang⁹, Xiangyong Zhao¹⁰, Haosu Luo¹¹

Affiliations

¹ Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, University of Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800, China. liudxu@outlook.com.
² University of Chinese Academy of Sciences, Beijing 100049, China. liudxu@outlook.com.
³ Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, University of Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800, China. yue.qingwen@student.sic.ac.cn.
⁴ University of Chinese Academy of Sciences, Beijing 100049, China. yue.qingwen@student.sic.ac.cn.
⁵ Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, University of Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800, China. dengjie@student.sic.ac.cn.
⁶ University of Chinese Academy of Sciences, Beijing 100049, China. dengjie@student.sic.ac.cn.
⁷ Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, University of Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800, China. lxbing@mail.sic.ac.cn.
⁸ Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, University of Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800, China. dwn@mail.sic.ac.cn.
⁹ Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, University of Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800, China. wang1972wang@hotmail.com.
¹⁰ Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, University of Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800, China. xyzhao@mail.sic.ac.cn.
¹¹ Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, University of Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800, China. hsluo@mail.sic.ac.cn.

Abstract

5-6 MHz PMNT/epoxy 1-3 composites were prepared by a modified dice-and-fill method. They exhibit excellent properties for ultrasonic transducer applications, such as ultrahigh thickness electromechanical coupling coefficient k(t) (85.7%), large piezoelectric coefficient d33 (1209 pC/N), and relatively low acoustic impedance Z (1.82 × 107 kg/(m2·s)). Besides, two types of Time-of-Flight Diffraction (TOFD) ultrasonic transducers have been designed, fabricated, and characterized, which have different matching layer schemes with the acoustic impedance of 4.8 and 5.7 × 106 kg/(m2·s), respectively. In the detection on a backwall of 12.7 mm polystyrene, the former exhibits higher detectivity, the relative pulse-echo sensitivity and -6 dB relative bandwidth are -21.93 dB and 102.7%, respectively, while the later exhibits broader bandwidth, the relative pulse-echo sensitivity and -6 dB relative bandwidth are -24.08 dB and 117.3%, respectively. These TOFD ultrasonic transducers based on PMNT/epoxy 1-3 composite exhibit considerably improved performance over the commercial PZT/epoxy 1-3 composite TOFD ultrasonic transducer.