Acoustic Emission Determination of Deformation Mechanisms Leading to Failure of Naval Alloys. Volume 2
Final rept. 27 Dec 1979-27 Dec 1982,
JOHNS HOPKINS UNIV BALTIMORE MD DEPT OF MATERIALS SCIENCE AND ENGINEERING
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An experimental investigation was conducted in order to determine the degree of acoustic emission signal modification due to propagation through specimens of different geometries. Initial efforts were directed at comparison of a number of acoustic emission probes in order to determine their sensitivity and their ability to detect an unmodified reproducible theoretically predicted waveform. The results of these tests showed that an optical interferometric probe possessed the largest frequency bandwidth and a National Bureau of Standards conical piezoelectric transducer possessed the best waveform detection sensitivity. These two probes were therefore selected to make measurements of the surface displacements due to a reproducible acoustic emission source as a function of distance from the source for several different geometrically shaped objects. Long test specimens in the form of a right circular cylinder, a rectangular cross-section bar, a moderately thin-walled pipe, and an I-beam were used for these propagation measurements.
- Marine Engineering