Laser Photoacoustic Technique for NDE
نویسندگان
چکیده
The technique of laser photoacoustic spectroscopy is applied to the studies of surface and sub-surface structures of solids in a nondestructive fashion. In the present case, special attention is focused on reaction-bonded Si N ceramics, which are used for the manufacturing of turbine blades. Good correlation is obtained betwee~ fhe observed photoacoustic signal and surface microstructures. In addition, the photoacoustic signal reveals inhomogeneities that are not visually detected under a microscope.
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