Micromechanics and Inhomogeneity pp 1-15 | Cite as
An Inverse Problem in Nondestructive Inspection of a Crack in a Plate with an Inhomogeneity by Means of the Electrical Potential Method
Abstract
A method was presented for the nondestructive evaluation of a crack on the back wall of an infinite strip having an inhomogeneity. The weldment is a typical inhomogeneous region as far as the electrical resistivity is concerned. The method was based on the distribution of d.c. electrical potential. The inhomogeneity problem was solved to determine the location, size, and inclination of the crack in the following way. First, a homogeneity problem was solved for a cracked strip, where the crack was modeled as a continuous distribution of singularities of the electrical potential. Next, the potential difference distribution was found for a plate without crack. By combining these two results, the crack geometry in the inhomogeneous strip was determined.
Application examples showed agreement between the evaluation and the actual crack observed in the weldment, and verified the applicability of the present method.
Keywords
Electrical Resistivity Stress Corrosion Crack Nondestructive Inspection Potential Distribution Current InputPreview
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