An improved resonator method for the determination of piezoelectric material constants

This paper presents an improved resonator method for the determination of piezoelectric material constants. The improved method addresses a fundamental limitation of the measurement methods recommended in the current IEEE Standard on Piezoelectricity: the relations between vibrator response and material constants presented in the Standard are based upon the one-dimensional approximation of an essentially infinite flat plate with a uniform distribution of vibratory motion. The calculation or measurement of the vibrational amplitude distribution is a non-trivial task. The practical result is that the current IEEE 176-1987 resonator method recommendations are of limited usefulness in the determination of “intrinsic” piezoelectric material constants. The limitation can be, however, readily overcome using an improved measurement technique based on measurands unaffected by the vibrational amplitude distribution. Improved technique, the measurands of choice are the zero-mass-loading, fundamental mode, TE antiresonance or LE resonance frequencies