Abstract
This thesis presents experimental results obtained by examining ultrasonic wave propagation through a layer of spherical lead inclusions embedded in a polyester matrix. Through transmission tests were conducted on several area fractions of inclusions with both periodic and random arrangements. Transducer sets having center frequencies of 0.25 MHz to 2.25 MHz were used for the tests. The rigid-body resonance of the particles was observed. The frequency of this resonance was found to be dependent on the area fraction of the layer. Similar results have been observed both theoretically and experimentally by other authors for particulate composites with a three dimensional dispersion of inclusions. A counter-intuitive result observed in this work is that the in-plane packing of the inclusions influences the out-of-plane resonance. Other resonances were also observed. A higher order particle resonance was detected in several specimens and a resonance due to the periodic dispersion of spheres was also seen.
Day, Nathan Allan (1994). Ultrasonic wave propagation through a layer of spherical inclusions with random of periodic arrangements. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -1994 -THESIS -D273.