CRACK INTERACTION IN NDE OF MULTIPLE CRACKS BY MEANS OF POTENTIAL DROP TECHNIQUE

Abstract A method is developed to evaluate crack interaction in NDE of multiple cracks by d.c. potential drop technique. A subregion containing m(=1,3,5,…) cracks are considered. The potential drop of the middle crack for each subregion are considered for two successive cases (m and m+2) and compared. The ratio of these two potential drops shows the effect of the first and last cracks of the subregion on the potential drop of the middle crack. Comparison of the potential drop of the middle crack with the potential drop of a single crack with the same depth and the same positions of potential probes shows the crack interaction. The method is based on the FEM. Experimental data verify the numerical results.