Holographic quantitative nondestructive evaluation

The efficacy of holography for quantitative NDE was shown for low modulus materials [1,2]. Due to their inherent damping property, rigid body disturbances during holography are minimal or absent. However these disturbances invariably occur for general materials affecting the sensitivity of the technique in addition to making the evaluation process difficult. It is shown that the second derivatives of fringe order (with respect to distance) provides data related to strains. The strains are not affected by rigid body movements and provide quantitative data on the effect of the defects present and the structural integrity. Demonstrative experimental data is provided for this.