A finite plate technique for the determination of piezoelectricmaterial constants

摘要

An improved resonator method is presented for the determination ofnpiezoelectric material constants. The improved method addresses anfundamental limitation of the measurement methods recommended in thencurrent IEEE Standard on Piezoelectricity: the relations betweennvibrator response and material constants presented in this Standard arenbased upon the 1-D approximation of an essentially infinite flat platenwith a uniform distribution of vibratory motion. The calculation ornmeasurement of the effects due to the nonuniform vibrational amplitudendistribution in a laterally bounded plate is a nontrivial task. Thenpractical result is that the current IEEE 176-1987 resonator methodnrecommendations are of limited usefulness in the determination ofn“intrinsic” piezoelectric material constants. Thisnlimitation can, however, readily be overcome using an improvednmeasurement technique based on measurands unaffected by the vibrationalnamplitude distribution. In the improved technique, the measurands ofnchoice are the zero-mass-loading, fundamental mode, thickness-fieldnexcitation (TE) antiresonance, or lateral-field excitation (LE)nresonance frequencies. A recommended experimental procedure, using thenpreferred measurands, is presented