The use of AC-held measurem ents for crack detection and sizing in air and underwater

Abstract

The use of AC-field measurements for crack sizing and detection is now common in many industries. It has been shown to be a simple and rapid method of sizing surface cracks, both in air and under water. Associated with the development of the Crack Microgauge has been the formulation of mathematical models of the electromagnetic fields, which has removed the need for calibration in many practical applications. This work is reviewed briefly. New versions of the instrument have recently been produced and novel applications are described.