Ultrasonic Inspection of Inhomogeneous Welds Simulated by Gaussian Beam Superposition

The presented Gaussian beam superposition technique allows for transducer field calculation in inhomogeneous anisotropic media. Due to the complex cuspidal shapes of the quasi-shear vertical (qSV) wavefronts in the austentic weld material, only qP- and SH-wave propagation has been addressed here. The approach uses a paraxial approximation, thus deviations from the exactly calculated field patterns only exist in the regions off the vicinity of the central ray [1,9]. The high computational efficiency of the method using a ten-term Gaussian beam solution is obvious: the calculation time for the results shown in Figs. 2 and 3 is about 20 seconds on a 233 MHz Pentium PC.