High-frequency ultrasonic transducer based on lead-free BSZT piezoceramics

This paper describes the fabrication and evaluation of a high-frequency (40 MHz) transducer based on lead-free piezoceramics for ultrasonic imaging. The transducer with an aperture size of 0.9 mm has been fabricated using barium strontium zirconate titanate ((Ba0.95Sr0.05)(Zr0.05Ti0.95)O3, abbreviated as BSZT) ceramics. The lead-free BSZT has a piezoelectric d33 coefficient of 300 pC/N and an electromechanical coupling factor kt of 0.45. High-frequency ultrasound transducers were fabricated and a bandwidth of 76.4% has been achieved with an insertion loss of −26 dB. Applications in high resolution biological and medical imaging could be possible with this lead-free material.

► A high frequency (40 MHz) lead-free BSZT transducer was fabricated and characterized. ► Comparable performance to lead-based transducers. ► −6 bandwidth of 76.4% and insertion loss of −26 dB. ► It is a promising candidate in the application of high-frequency transducers.