Fabrication and Characterization of Lead-Free BNT-6BT Ultrasonic Transducers Designed by an Intelligent Optimization Algorithm

• Published in: Crystals (Basel) Vol. 12; no. 8; p. 1181
• Main Authors: Zhang, Junshan, Zhao, Jianxin, Quan, Yi, He, Jingrong, Li, Yi, Wang, Zhe, Zheng, Kun, Zhuang, Jian, Jiang, Zhishui, Wen, Li, Ren, Wei
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.08.2022
• Subjects: Accuracy; acoustic tweezer; Acoustics; Back propagation networks; Bandwidths; Biomedical materials; BNT-6BT lead-free ceramics; Circuit design; Design optimization; Design techniques; Efficiency; Electric fields; Equivalent circuits; Genetic algorithms; Lead free; Morphology; Neural networks; Optimization algorithms; particle swarm optimization algorithm; Piezoelectric ceramics; Polystyrene resins; Software; Testing; Transducers; ultrasonic transducer; Ultrasonic transducers; China; United States > US
• ISSN: 2073-4352; 2073-4352
• DOI: 10.3390/cryst12081181

Lead-free piezoelectric material-based ultrasonic transducers have been researched for several years, but the inefficient properties and design difficulties have troubled lead-free ultrasonic transducers for a long time. To improve the performance and design efficiency of lead-free ultrasonic transducers, in this work, an equivalent circuit model and intelligent optimization algorithm were combined for use in a transducer design. Firstly, 0.94(Bi0.5Na0.5)TiO3-0.06BaTiO3(BNT-6BT) lead-free piezoelectric ceramics were prepared and characterized. Then, BNT-6BT ceramics were used to fabricate the ultrasonic transducers. An equivalent circuit model-based software, PiezoCAD, and a genetic algorithm-based back-propagation neural network were used to optimize the design of the transducers. A 3.03 MHz center frequency and 60.3% −6 dB bandwidth of the optimized transducers were achieved, which were consistent with the neural networks optimization results. To verify the application potential of the lead-free transducers, tungsten rods phantom imaging and polystyrene spheres with 300 μm diameter manipulation were completed by the transducers, and the experiment results indicate that the BNT-6BT lead-free transducers have great potential in further biological and biomedical applications.