The objective of this Phase I proposal is to gain sufficient information about the ultrasonic response as a function of surface roughness so that an instrument to measure surface roughness can be developed in the future. The basic concept of the ultrasonic technique is that the backscattered energy from an impinging ultrasonic wave decreases as the surface roughness increases. At the same time, the energy in the scattered radiation component increases. Both of these approaches will be investigated in an attempt to maximize the ultrasonic response to surface roughness. These results will lead to an improved understanding and a model that should provide insight for the development of an ultrasonic instrument for dynamic, in-process surface roughness measurement. If successful, a Phase II proposal is planned.
