A POLYNOMIAL FIT FOR CALCULATING THE ELECTROMECHANICAL COUPLING-CONSTANTS OF PIEZOELECTRIC MATERIALS USING THE METHOD DESCRIBED

The usual methods for determining the electromechanical coupling constants of piezoelectric materials are described in the IEEE standard on piezoelectricity (IEEE Standard on Piezoelectricity 176-1987). When spurious resonances are present, the standard recommends the use of a method that involves the use of a numerical table of corresponding values. In order to allow for atuomation of this method, a polynomial function that gives a good fit to the numerical table has been found.