Optimization of electrical-potential methods of measuring crack growth

Publisher Website
Google Scholar
Abstract
This paper describes an alternating-current electrical-potential system for measuring crack growth that is more sensitive than a corresponding direct-current system and which is capable of a discrimination in crack length of approximately 20 μm. It shows how the positions of the current supply and potential sensing leads can be optimized using two-dimensional finite-element and boundary integral equation methods. Both methods give calibrations which are in good agreement with optical measurements of crack growth and with measurements made using a graphitized electrical analogue paper technique. The boundary integral equation approach is shown to he the more efficient to use for a range of geometries, since it is only necessary to specify the shape of the boundary and redundant information at internal nodes need not be obtained.

This publication has 18 references indexed in Scilit: