Biased lead zirconate titanate as a high-power transduction material

Abstract

High-power, underwater transducers utilizing polarized piezoelectric ceramic material are usually limited in drive amplitude so that depolarization does not occur, but application of a dc bias field in the polarization direction allows the use of higher ac drive fields. To demonstrate the feasibility of biased operation as a means of achieving higher power, a thin-walled, spherical-shell transducer was constructed of Channel 5800 and tested in NUWC's Acoustic Pressure Tank Facility at a hydrostatic pressure of 1400 psig ͑9.65 MPa͒. The transducer was successfully driven to 33 V/mil ͑1.3 MV/m͒ rms with an accompanying bias field of 31 V/mil ͑1.2 MV/m͒. The source level was 206 dB re: 1 Pa•m at 61 kHz, corresponding to a 10-dB improvement over the unbiased drive limit of 10 V/mil ͑0.4 MV/m͒ rms and 196 dB re: 1 Pa•m.

Electromechanical properties of high coupling single crystals under large electric drive and uniaxial compression

“…Therefore, high energy density transducer materials were required as alternatives to PZT. In the last few years, a number of new high power, active, sonar materials such as Terfenol [1], ceramic lead magnesium niobate-lead titanate (PMN-PT) [2], and biased PZT8 ceramics [3] have been developed with high 33-mode coupling and high strain. The resulting sonar transducers will exhibit increased bandwidth and energy density.…”

<title>Material challenges for transducer designers in the 21st century</title>

“…The cost of PMN is also an issue that may only be resolved with high volume production. Recent work on biased PZT 68,69 indicates that a minimum of 6 dB can be gained by biasing conventional PZT and that realization has somewhat dampened the enthusiasm over PMN. The most exciting development in electroactive material is the emergence of single crystal PMN-PT and PZN as high strain ceramic materials.…”

“…DC biasing of PZT piezoelectric ceramic permits considerably higher drive fields to be imposed on the material without damage and results in performance gains that are significant. Recent work by Moffett et al 3 heralded the performance improvements achievable in a sphere transducer and Penn State researchers demonstrated potential power gains 4 with a traditional tonpilz. To a limited extent, there have been prototype Terfenol-D tonpilz transducers fabricated and tested and with proper design they can be efficient and high powered.…”

Dielectric Loss Reduction of Ferroelectric Lead Magnesium Niobate-Lead Titanate Sound Projector Drivers

“…Therefore, high energy density transducer materials were required as alternatives to PZT. In the last few years a number of new high power active sonar materials such as Terfenol [1], ceramic PMN-PT [2], biased PZT8 ceramics [3], and single crystal PMN-PT [4] have been developed with high 33 mode coupling and high strain. The resulting sonar transducers will exhibit increased bandwidth and energy density.…”