Ultrasonic 2-D SH crack detection in anisotropic solids

A 2-D SH flaw scattering model in anisotropic media is developed in this paper. The situation to be simulated is the scattering of waves generated by a probe incident upon an infinite strip-like flaw between two different homogeneous anisotropic solids. The scattering problem is solved by combining a 2-D SH probe model with a 2-D SH scattering model for an incoming plane wave. The probe model is based upon the assumption that the traction is known at the probe interface and the flaw is modeled by the so called spring boundary conditions. The solution is obtained by means of Fourier methods. In addition to the displacement field, a probe signal response which is directly proportional to the voltage output in a pulse-echo experiment is calculated. Numerical examples are presented both in the frequency and the time domain for the total displacement field and in the time domain for the probe signal response for two fictitious material configurations. An example where the flaw is a surface-breaking crack is also given.