We have developed a transducer which allows the benefits of Line Focus Beam (LFB) acoustic microscopy to be realized over large areas, using a conventional pulser-receiver. Experimental evidence is presented to show that the transducer is correctly modeled in detail by Green?s function theory, and that all relevant wave speeds can also be predicted using a much simpler geometrical ray model. Data obtained by simply rotating the transducer a fixed distance above the specimen are presented using grey-scale plots which establish the ease with which anisotropy can be revealed. Finally, a grey-scale plot of rotational-scan data recast in terms of velocity is shown to demonstrate the simultaneous detection of both surface and pseudo-surface waves in the same crystallographic orientation of a silicon specimen.
Proceedings Title: Proceedings of the First US-Japan Symposium on Advances in NDT
Conference Title: American Society for Nondestructive Testing
Pub Type: Conferences
Nondestructive evaluation, Ultrasonics