Comparing infrared thermography and ESPI for NDE of aircraft composites

Infrared Thermography is gaining acceptance by industry as a suitable non destructive testing and evaluation (NDT/E) technique. Likewise Electronic Speckle Pattern Interferometry (ESPI) has also been shown to be suited for similar purposes, particularly for the inspection of composite materials. This paper presents the theory of the two inspection methods. Selected composite samples containing defects are subjected to identical inspection procedures using both techniques. The results are presented and compared with each other. From the results it is clear that both techniques are suited for the detection of the defects in the composite sample. The results also indicate that ESPI is a more sensitive inspection technique than IRT. Comparisons are drawn and the benefits of each technique discussed.