Showing papers by "William H. Prosser published in 1991"

Harmonic Generation Measurements in Unidirectional Graphite/Epoxy Composites

Abstract: A consideration of nonlinearity is essential for describing many important physical phenomena and processes in solids. The determination of nonlinearity is of importance for the characterization of materials, especially the newly developed ones. The existing techniques for measurements of the nonlinearity can be divided into two main categories. One is the measurements of strain dependence of the ultrasonic velocity (induced by stress, temperature, etc.). The other is the measurements of the harmonic generation in the solids.

Methods of determining loads and fiber orientations in anisotropic non-crystalline materials using energy flux deviation

Abstract: An ultrasonic wave is applied to an anisotropic sample material in an initial direction and an angle of flux deviation of the ultrasonic wave front is measured from this initial direction. This flux deviation angle is induced by the unknown applied load. The flux shift is determined between this flux deviation angle and a previously determined angle of flux deviation of an ultrasonic wave applied to a similar anisotropic reference material under an initial known load condition. This determined flux shift is then compared to a plurality of flux shifts of a similarly tested, similar anisotropic reference material under a plurality of respective, known load conditions, whereby the load applied to the particular anisotropic sample material is determined. A related method is disclosed for determining the fiber orientation from known loads and a determined flux shift.