ELASTIC AND PIEZOELECTRIC CONSTANTS OF BA2NANB5O15

The elastic, piezoelectric, and dielectric constants of Ba 2NaNb5O15 have been measured. The experimental techniques used involve mostly thickness-mode measurements made on small plate-shaped samples of various crystallographic orientations. As reported previously, the z-cut plate has a thickness longitudinal mode coupling factor of 0.57, which makes this material attractive for application as a high-frequency longitudinal mode transducer. However, from the measured constants and the theory of piezoelectric plate vibrations, it is determined that no crystallographic orientation other than the z-cut has properties suitable for ultrasonic transducer applications. © 1969 The American Institute of Physics.