Acoustic mixing in a dome-shaped chamber-based SAW (DC-SAW) device

A dome-shaped chamber device enables the maximizing of the effect of SAW transmitted at a Rayleigh angle.

EVALUATION OF SUB-SURFACE MATERIAL PROPERTIES USING MINIMUM REFLECTION PROFILES METHOD

Backscattered Rayleigh waves from the surface and/or sub-surface of specimens can be changed by scatterers such as micro-cracks, grain boundaries and surface roughness as well as by variations in material properties. In fact, rough surface generates higher energy of backscattered Rayleigh wave than smooth one. So, it is strongly needed to have a quantitative method to evaluate the variation of material properties only. To address such a need, we propose a new method, named as "minimum reflection profile" which measures energy variation of reflected waves from the surface of specimens as changing the angle of incident wave from normal to beyond Rayleigh angle in a pitch-catch immersion setup. Because of minimum reflection profile is less sensitive to roughness of surface than backward radiation profile. Also, we explore performance of the minimum reflection profiles by evaluating the sub-surface material properties of well known materials with various material properties.