Application of Digital Shearography for Non Destructive Testing of material with Thermal Loading

Shearography has proved to be a highly effective nondestructive testing (NDT) method، especially when it comes to composite and polymer materials used in automotive، aerospace engineering، nuclear and oil industries. Although its application in material testing and material research already has achieved acceptance in research، its applications need a highly considerations in limitations and its parameters. In this paper the application of digital shearography in the defect detection of polymer materials is studied. In this regard، a proper set-up of shearography is presented. A polyethylene plate with several defects in different sizes and depths have been made and tested with the presented set-up. The shearograms then have been compared to evaluate the shearographic system in defect detection. The effects of shear size and system of thermal loading have also been studied.