A non-destructive technique for the elastic characterization of thin isotropic plates

The paper presents a non-destructive technique for determining the dynamic elastic properties of isotropic thin square plates. It is based on the measurement of at least two of the first four resonant frequencies of the samples and allows to determine the elastic constants directly using polynomial interpolating functions. These functions are derived from suitable data obtained by means of finite element analyses. The procedure is tested on metallic and ceramic specimens. Samples are excited to vibrate by drivers with continuously variable frequency output or by impact. The effect of the different sources of error on the calculation of elastic properties is also discussed.