Ultrasonic transducer with BiScO3-PbTiO3-based ceramics of operating temperature over 400°C

Ultrasonic transducers are widely employed in many fields such as non-destructive testing (NDT), petrochemical refineries, aerospace field, etc., in which high temperature ultrasonic transducers are necessary because many measurements must be done at elevated temperature. In this work, 4.5 MHz high temperature ultrasonic transducers with delay line were designed and fabricated based on BiScO3-Pb(Ti0.99Zn0.01)O-3 (BS-0.01PZnT) piezoelectric ceramics possessing excellent temperature stability and high Curie temperature. The experimental results revealed that-6 dB bandwidth and the center frequency of high temperature ultrasonic transducers are around 129% and 4.5 MHz, respectively, which are almost stable from room temperature to 400 degrees C. The peak-to peak values (V-pp) is as large as 1.5 V at RT, indicating very high sensitivity. More importantly, the ultrasonic transducers with customized BS-0.01PZnT ceramics can work reliably at high temperature of 380 degrees C and 450 degrees C by in-situ measurement at elevated temperatures. This work verifies the great potential application values of ultrasonic transducers with BS-0.01PZnT ceramics in high temperature applications.