Model for ultrasonic field analysis in solids*

In this paper a theoretical model is presented that can be used to evaluate analytically ultrasonic transducer longitudinal wave-generation characteristics in homogeneous isotropic solids. Comparisons with fluid-type solutions are also outlined. A continuous wave solution is determined first, from which particle displacement, particle velocity, and stress solutions for arbitrary pulse shapes are obtained. The ultrasonic field distributions resulting from several basic pulse shapes are presented along with the results of an experimentally obtained distribution. Nearfield and beam angle of - divergence for pulse output transducers are also discussed. In addition to developing data for ultrasonic field analysis in solids, the equations developed can be used for obtaining solutions to many other ultrasonics problems. For example, it now becomes possible to develop equations that can analyze the resulting stress and particle velocity distribution in a multilayer structure for materials subjected to either normal beam incidence or angle beam incidence. The work may also be extended to include many aspects of ultrasonic field measurement analysis for flaw characterization work.