Modeling of Sound Fields through Austenitic Welds

The propagation paths of ultrasonic waves through austenitic weld material are difficult to predict due to the anisotropic and inhomogeneous structure of the weld. To support an NDT-inspector a ray tracing algorithm has been developed to follow longitudinal, horizontal and vertical polarized shear wave propagation starting from the basic material through the anisotropic weld to the opposite side in forward or in backward direction. Grain orientation, elastic constants, insonification direction, mode conversions and probe sizes are entered into the program according to the experimental reults. The algorithm allows to model and visualize the effect of the transversely homogeneous modeled weld and to optimize the experimental set up to obtain as much information from a weld seam defect back to the probe as possible