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The reversible ferroelectric-ferroelectric transition of morphotropic relaxor-ferroelectric lead zinc niobate-lead titanate and lead magnesium niobate-lead titanate single crystals as accessed by the mechanical compression is presented. Implications of the observation for sound projectors are presented.

A study of fabrication and characterization results of piezoelectric micromachined ultrasonic transducers (pMUTs) based on 2-micrometer thick Pb(Zro.53Tio.47O3) (PZT) thin films is described. A transmit-receive experiment with two quasi-identical pMUTs showed significant signal transmission up to a distance of 20cm in air and 2 cm in the test liquid.

A diaphragm-type piezoelectric micromachined ultrasonic transducer (pMUT), a composite coating technique based on chemical solution deposition and high-energy ball milled powder used to fabricate thick PZT films, and micromachining of the pMUTs using thick films is investigated. Results suggested that the fabricated pMUT has very good ultrasound-radiating performance and can be used to compose pMUT arrays for generating ultrasound beam with high directivity in numerous applications.

Usage of light diffraction tomography to measure the acoustic field of micromachined ultrasonic transducers (MUT) in cases in which standard methods like hydrophone and microphone measurements fail is demonstrated. The results reveal that the air-coupled MUTs in the frequency range of about 1MHz as well as the extreme near field of a miniaturized continuous wave 10 MHz water-loaded transducer were successfully characterized with light diffraction tomography.

Manganese modified (1-x)BiScO3-(x)PbTiO3 (BSPT) compositions near the morphotrophic phase boundary are investigated and the electrical behavior is characterized at high temperatures, and a full set of material constants is determined using the resonance method. Studies revealed that these data should provide a basis to perform future theoretical analysis as well as device design, the temperature of the properties and very high RC modifying BSPT as a new material for high temperature actuation and sensing applications.

A study is conducted to investigate the length extensional (33-mode) electromechanical properties and their stability for morphotropic (001) oriented and poled multidomain PMN-PT single crystals when driven by a large electric field under a combined DC bias field and compressive mechanical stress. It is found that the remarkable small signal length extensional coupling (K33 > 0.99) and other electromechanical properties of morphotropic PMN-PT single crystals prevail under large drive.

Improvements of the d(sub 33) co-efficient for thick-film lead zirconate titanate (PZT) layers are detailed. The combination of small and large particles does increase the d(sub 33) of the film and justifies the investigation and it is shown that the consistency of the results can be increased in comparison to the ball milled devices, although they are not as consistent as the attritor3 devices.