Thermographic crack detection by eddy current excitation

Eddy current thermography is a new NDT-technique for the detection of cracks in electroconductive materials. It combines the well established inspection techniques eddy current testing and thermography. The advantage of this method is to use the high performance of eddy current testing without the known problem of the edge effect. Especially for components of complex geometry this is an important factor which may overcome the increased expense for inspection set-up. The principle of this technique and an algorithm to increase the sensitivity for small defects are described. Some inspection examples on aero engines parts are presented which show the potential of eddy current thermography.