In-Situ NDE of Navy Sonar Domes Via X-Ray Backscatter Tomography

Underwater X-Ray Tomography Using Compton Backscatter Imaging

“…It can be shown, by algebraic manipulation of equations for the three stages [3], that the signal intensity corresponding to a point Pis (2) where: k is a system parameter encompassing all parameters constant in a given inspection set-up; pep) is the physical density at point P; x and x' are the path lengths of the primary and scattered rays. According to (2) we can expect an unambiguous interpretation of the signal as a function of the material density. This is in fact our experience with homogeneous materials.…”

“…The current method, radiography, requires not only costly drydocking but also dome removal from the ship. Previously, we have reported on our feasibility study and our development of a prototype dome inspection system leading to the successful demonstration of in-situ dome inspection in drydock [1,2]. Since then, we have developed and demonstrated an underwater system.…”

X-Ray Backscatter Evaluation of Porosity Distribution in Low Density Porous Magnesium

“…This niakes x-ray tomography possible in applications where computed tomography (CT) is precluded by the object's inaccessibility, size, or aspect ratio. In the course of developing an XBT system for the underwater inspection of naval sonar domes [3], we have investigated other applications that exploit this capability. One such application is the evaluation of porosity distribution in porous metal plates.…”

A Practical Algorithm for Reconstruction From X-Ray Backscatter Data

“…Although numerous applications of x-ray backscatter tomography (XBT) have been demonstrated, only a few have been fully developed to practical implementation [1][2][3][4][5]. In some applications the images produced by direct data acquisition and display methods are plagued with superposition artifacts that can interfere with interpretation [6].…”