Shape reconstruction of flaws in inhomogeneous cylinders

In this article, three dimensional Kirchhoff inverse scattering method is modified to convenient form for two cylindrical specimens that include three dimensional defects. Two inhomogeneous cylinders with flaw models are prepared and ultrasonic measurements are carried out. The measurement area in the modified methods is restricted in the plane perpendicular to the axis of cylindrical specimen. That´s to say that the method is modified to convenient form to use measured waveforms in the x1-x2 plane. The measured wave data are fed into the inversion method and cross-sectional images are obtained. From the experimental research for two kinds of defects, it is verified that the Kirchhoff inversion works well for both volumetric defects and surface defects.