High Power Characteristics of Lead‐Free Piezoelectric Ceramics

Abstract

High power characteristics of lead‐free ( Bi , Na ) Ti O 3 ( BNT ) and Ba Ti O 3 ( BT )‐based piezoceramics were investigated and compared to commercial “hard” Pb ( Zr , Ti ) O 3 PZT materials. Acceptor‐modified BNT and BT ‐based ceramics showed typical “hardening” characteristics, exhibiting high mechanical quality factor Q m > 800 and low dielectric loss, <0.01, comparable to “hard” PZT ceramics. Of particular significance is that BNT ‐based ceramics were found to exhibit minimal variation of resonance frequency shift and high Q m under high level vibration velocity, being ~0.6% and ~800 at 0.25 m/s, respectively, due to the high domain stability associated with their high coercive fields, being on the order of 35 kV/cm.