Crack Detection Using EddyTherm

Abstract

The EddyTherm thermographic crack detection method uses brief pulsed eddy currents to heat metallic components under inspection. Cracks, if present, will disturb the current flow and so generate changes in the temperature profile in the crack area. These temperature changes are visualized using a thermographic camera. The advantages afforded by the method are its very brief inspection times, its ability to inspect complex geometries, its excellent flaw detection sensitivity and its ability to detect hidden, subsurface cracks. Simulation of inductive heating using FEM methods permits coils to be adjusted and inspection parameters optimized. The use of a robot to manipulate parts under inspection, a high‐frequency pulse generator for inductive heating and enhanced algorithms enabled a demonstrator to be set up for the fully automated crack inspection of engine compressor blades.