Preparation and characterization of acoustic transducers based on lead-free ceramics

The driving force for developments of lead-free piezoceramics results from environmental concerns and issued regulations by the EU. Strong support of R&D activities during the recent years resulted in a significant step forward in the development of lead-free alternatives with KNN based ceramics as one of the most promising candidates. In our work we studied possible benefits for ultrasonic transducer applications that may arise from much lower acoustic impedance of KNN based piezoceramics, compared to conventional PZT materials. According to our results, KNN based ultrasound transducers are expected to have high potential for high frequency, wide band applications especially for objects with low acoustic impedance.