Determination of the Deflection of a Cantilever Beam and Poisson's Ratio by Holographic Interferometry

Abstract

This paper discusses about the technique to determine the surface deflection of a cantilever beam subjected to a point load by using a double-exposure holographic interferometry. The computer generated holographic fringe pattern compares very well with the experimental result. The obtained fringe pattern represents both deflection and anticlastic behavior of the surface of the beam due to the three dimensional effect. Combining the anticlastic behavior with the beam theory we could get poisson's ratio of the material. Experimental result using aluminium alloy 6061-T6 as a cantilever beam indicates that its poisson's ratio is equal to 0.355 which agrees with the value in the published data to within 2.3%