Abstract: Electronic shearography has emerged as a promising newtechnology for non-contacting, full-field opticalnondestructive evaluation. In particular, the`common-path' interferometric configuration that istypically used with shearography offers greaterimmunity to environmental disturbances as compared totraditional electronic speckle pattern interferometry(ESPI) or holographic interferometry. This advantagegives electronic shearography a potential edge fortesting applications in industrial environments. Thispaper presents results of recent experiments towardsevaluating the capability of electronic shearographyfor the inspection of aluminum airskin structures. Thedefect classifications targeted in this study includeddisbonds in adhesively bonded skins as well as fatiguecracks emanating from rivet holes. Selection of aneffective loading strategy to isolate the defectregions in the fringe patterns was a primaryconsideration in this study, as with any type ofinterferometric inspection. Vacuum stressing provedeffective locating disbonds while mechanical pointloading with vacuum grippers was used to identifyfatigue cracks. In each case, the resolution of theshearographic inspection technique was intrinsicallydependent on the size of the field of view. !8
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