Analysis of Interaction of Multiple Cracks in a Direct Current Field and Nondestructive Evaluation

Abstract

A method of analysis is proposed for nondestructive evaluation of multiple cracks by means of the d.c. (direct current) potential drop technique. Two and three-dimensional multiple cracks are treated. A methodology for considering interaction of cracks based on the equation for an isolated crack is given to calculate the potential drop between both sides of a crack in multiple cracking in a plate. The inverse problem to evaluate the crack depth is analyzed by comparing the potential drop calculated in this way with the measurement. It is shown that the evaluated crack depth is in good agreement with the actual one.