Computerized ultrasonic ray tracing in austenitic steel

A method of ray tracing for elastic waves in inhomogeneous anisotropic media is presented. An analytical solution of the wave equation in a general elastically anisotropic medium is used. Inhomogeneity is treated using numerical methods: discrete steps are taken in a ray path with matching of suitable boundary conditions across each step. We then discuss the validity of these methods and of the assumptions which have been made. We discuss briefly the set of Fortrn 77 programs, which we have called RAYTRAIM, used for this work. These programs can be applied to any three-dimensional geometry, composed of one or more different media whose structure can be defined in the form required by the input data. Finally, some preliminary results of this work are applied to the case of an austenitic V-butt weld, with a spatially varying grain structure, examined ultrasonically. The relevance of these results to ultrasonic non-destructive testing is discussed.