Determination of elastic modulus of a beam by using electronic specklepattern interferometry

摘要

This paper proposes a sonic resonance test for an elastic modulus measurement which is based on theelectronic speckle pattern interferometry. Previous measurement technique of elastic constant has thelimitation of application for thin film or polymer material because contact to specimen affectsthe result. It has been developed as a non-contact optical measurement technique which can visualizeresonance vibration mode shapes with whole field. The maximum vibration amplitude at eachvibration mode shape is a clue to find the resonance frequencies. The dynamic elastic constant of testmaterial can be easily determined from vibration of a beam equation using the measured resonancefrequencies. The proposed technique is able to give high accurate elastic modulus of materials through asimple experimental set-up and analysis. The experimental result also compared to the theoreticalresult.