Three Dimensional Scattering of Elastic Waves by Surface Corrosion Pits

Elastic wave scattering by surface defects like cracks, corrosion induced pits, topographic irregularitieSv etc., is of interest for ultrasonic nondestructive evaluation and in seismology. Scattering by surface-breaking cracks has been studied by many authors in recent years. References to papers on scattering by surface-breaking cracks can be found in [1,2]. The corresponding problem of cavities at the surface and topographic irregularities has been studied in seismology (see, for example, [3,4]). Almost all the studies have dealt with two-dimensional problems (for references to some 3-D scattering see [5])