Laser Ultrasonic Imaging of Structural Microcracks
نویسنده
چکیده
Lasers provide a non-contact and remote inspection method with high resolution and sensitivity. As a crack detection tool, laser ultrasonics can be used to image surface-breaking cracks with microscopic precision. By monitoring the local elastic scattering conditions and dynamic motion fields present in the immediate vicinity of a surface-breaking crack site, the local crack morphology can be mapped out in significant detail. Several crack imaging examples are provided for imaging and characterizing microscopic, surface-breaking cracks in aerospace superalloys. Brief overviews of laser probe methods, displacement-field imaging, and crack imaging are discussed.
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