Vibration Method for the Elastic Constants of Small Plates

A method is described in which a clamped mode of vibration is used in order that the driving force may exceed the weight of the specimen. A supported cantilever plate is vibrated in flexural and torsional modes by driving the support. An approximate solution of the vibration equation is used to calculate the elastic constants from the resonant frequencies. The solution is expressed in terms of the ratio of the resonant frequency of the unknown specimen to that of a standard of the same length and width, to reduce the precision required in specification of the support location. This method was applied in a radiation effects study to measure the Young's moduli of small ceramic plates within 3–5%. The accuracy was limited in this instance by the dimensional tolerances of the specimens.