A Hemispherical Test Fixture for Measuring the Wave-Fields Generated in an Anisotropic Solid

The design and fabrication of an experimental system for measurement of wavefields in anisotropic materials are described. In the test fixture, a source transducer is affixed to the flat portion of a hemisphere of the anisotropic solid. A receiving transducer having a large field of view (FOV) is scanned over the surface of the hemisphere by a motorized C-arm, mapping out the wavefield generated in the specimen. The hemispherical shape of the test specimen permits scanning the wavefield over nearly a full 2π solid angle, an improvement over the limited angular range afforded by a flat panel of the anisotropic solid. The authors report the results of preliminary experiments designed to evaluate the fixture