Short-fiber piezocomposite and its bandwidth enhancement for high-frequency medical ultrasound transducer

High performance 1–3 piezocomposite is crucial to high-frequency medical ultrasound imaging as its performance enhancement to an ultrasound transducer. A bandwidth enhancement effect had been found when a novel PZT-based short-fiber piezocomposite was fabricated and applied in the transducer. The electromechanical coupling coefficient k t of the short-fiber piezocomposite was as high as 63% at high frequency. An ultra-high bandwidth of the ultrasound transducer obtained to be 131.6% @-6 dB. The high performances of the piezocomposite were owing to the longitudinal vibration enhancement and lateral vibrations depression which were derived from the shape and randomized distribution of the ceramic pillars, respectively. It indicates that the PZT short-fiber piezocomposite is a promising candidate for commercial high-frequency medical ultrasound transducers.