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This paper reports the most recent investigations on the detection of deep lying defects in nonmagnetic materials using Lorentz force eddy current testing (LET). Whereas classical eddy current testing techniques are limited due to the frequency dependent skin depth LET is expected to overcome this particular disadvantage by exploiting the induction of eddy currents by moving an electrical conductor in the vicinity of a permanent magnet. The detection of deep lying defects is examined at relatively high testing velocities and with high spatial resolution. Without target-oriented improvements defects in a depth of up to 6 mm under the surface can be detected and localized. Keywords: Lorentz force eddy current testing, deep Iying defect, permanent magnet, nondestructive testing

The primary aim of this work is to present a new 2D/3D numerical technique providing fast calculation of Lorentz forces acting on a permanent magnet moving relatively to a solid electrically conducting object. This specific field configuration represents a typical problem arising in novel Lorentz force eddy current testing applications. The proposed technique is based on several model simplifications which enable considerable reduction of the total simulation time while maintaining the accuracy oe the solution. For evaluation of the computational requirements and verification of the obtained results the wellestablished sliding mesh technique (SMT) has been used. The full paper will comprise the experimental validation of the obtained resuIts as weil. Index Terms - Eddy currents, finite element methods, Lorentz force, nondestructive testing