BCHT lead-free piezoelectric ceramics preparation and ultrasonic transducer fabrication via powder injection molding using simple binder

摘要

(Ba0.85Ca0.15) (Hf0.10Ti0.90)O3(BCHT) ceramics were prepared via the powder injection molding process using paraffin as simple injection binder. Rather pure perovskite BCHT ceramics are obtained sintered at different temperatures, and complex multi-ferroelectric phases coexistence is confirmed by XRD measurement. Although the relative density is around 90%, well densified microstructural morphology is obtained without detectable gas pores. Curie temperature (TC) and dielectric constant maximum (εm) change irregularly with sintering temperature, and the BCHT ceramics present complex ferroelectric nature. All the ceramics show easy polarization characteristic, and the 1540?°C sintered BCHT ceramics present the largest piezoelectric constant d33?=?554.6?pC/N. Thickness mode ultrasonic transducer was fabricated based on the 1450?°C sintered BCHT ceramics, where the bandwidth @-6?dB (BW-6 dB) is 56.25% and sensitivity is ?31.867?dB. PiezoCAD software simulation data present good agreement with the experimental results, showing promising applications for non-destructive testing using the BCHT lead-free ceramics.