Guided Wave Scattering by a Cylindrical Flaw

Abstract

The evaluation of adhesive bonds involves the detection of the continuity of the adhesive and also its effective elastic properties. There are several advantages in employing guided waves for interface testing: the intensification of the measured effects along the path of the wave propagation, the possibility of testing very thin adhesive layers, only one dimensional scanning is necessary and they are less sensitive to the variations in the properties of the adherends relative to the method of ordinary bulk ultrasonic wave. The impinging guided ultrasonic wave is scattered by flaws embedded inside the adhesive layer. By examining the characteristics of the scattered field from the flaw, it is possible to extract useful information about the flaw location and its dimension. This study presents a computational solution to the ultrasonic scattering of guided waves, in an adhesive layer, by a cylindrical flaw. The scattering field contains information about the integrity of the adhesive layer. We consider the case of an adherend-adhesive-adherend sandwich. The adhesion strength is assumed to be good and uniform.