Driving Electric Field Effects on Piezoelectric Transducers

Electromechanical properties for lead zirconate-titanate Pb(Zr x Ti 1- x )O 3 (PZT) based ceramic and lithium niobate LiNbO 3 (LN) crystal piezoelectric transducers were studied from a driving electric field viewpoint. The vibration velocity linearly increases with the driving field for a 128°-rotated Y-cut LN transducer and its maximum vibration velocity which can be used is 2.7 m/s when driven with the driving field of 7 ×10 2 V/m. The transducer is mechanically broken when driven with a higher field. The vibration velocity for the PZT based ceramic transducer initially increases with an increasing field and then gradually converges onto a certain value accompanied by heat generation. These phenomena are caused by the decrease in the mechanical quality factor with an increasing field. The 0.45PbZrO 3 –0.45PbTiO 3 –0.10Pb(Mn 1/3 Sb 2/3 )O 3 ceramic transducer is capable of generating 0.68 m/s with 5.5 ×10 3 V/m.