Article

High electromechanical coupling piezoelectrics: relaxor and normal ferroelectric solid solutions

International Center for Actuators and Transducers, Materials Research Laboratory, The Pennsylvania State University, University Park, PA 16802, USA
Solid State Ionics 01/1998; DOI: 10.1016/S0167-2738(98)00017-4

ABSTRACT A new category of piezoelectric ceramics with very high electromechanical coupling was discovered in a lead zinc niobate–lead titanate solid solution in a single crystal form. The maximum coupling factor k33 reaches 95%, which corresponds to the energy conversion rate twice as high as the conventional lead zirconate titanate ceramics. This paper reviews the previous studies on superior piezoelectricity in relaxor ferroelectric: lead titanate solid solutions and on the possible mechanisms of this high electromechanical coupling.

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