While the electromechanical coupling coefficient of piezoelectric crystals is commonly determined by measuring the resonant and ant resonant frequencies of the electrical impedance of the crystals, this method has had little use in evaluations of Kagnetostiictive material. To enable the advantages of this method to be exploited in Kagnetostiictive work, an analysis is presented in this report which shows the application of reso-nance-antiresonance measurements to Kagnetostiictive cylindrical-shell vibrators. Formulas are derived for the determination of the effective elec¬tromechanical coupling coefficient and mechanical Q, and the results are applied to the calculation of equivalent-circuit parameters. Dissipation is neglected in most of this analysis, but corrections are applied to leakage inductance. Formulas are presented for determining fundamental material constants from data for short, thin cylinders, and a comparison of the reso-nance-antiresonance method with the impedance-circle method is made. The results of this analysis are particularly useful for the evaluation of Kagnetostiictive ferrites.
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