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160824-N-N0204-001.JPG Photo By: Daniel Parry

WASHINGTON, D.C. - Crack detection in riveted lap joints with fiber laser acoustic emission sensors: The graphic shows the initiation and growth of cracks between rivets in a lap joint in the top left. A fiber laser sensor (illustrated in the top right inset), adhered to the structures, measures the acoustic emission signals generated by the cracks and software records them as acoustic events (AE). A typical AE event is shown in the lower right plot. The amplitude of the AE events as a function of time is shown in the lower left plot. Large increases in AE event amplitude are seen when the cracks grow. (U.S. Naval Research Laboratory) RELEASED


This photograph is considered public domain and has been cleared for release. If you would like to republish please give the photographer appropriate credit.

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