Vector Fields

Magnetic particle inspection (MPI) is one of the oldest NDT techniques and it is the most common method used to detect surface defects in ferromagnetic materials. But since the beginning MPI has been based on experiments, experience and on subjective judgements. This. contribution shows for the first time how MPI of complex shaped parts can be designed objectively by applying Maxwell equations and finite element calculations. The comparison between modelling and measurement shows substantial agreement. Results are given and discussed especially for automotive components like crankshaft and hub under DC- as well as AC-magnetization using coils and yokes. INTRODUC TI ON Magnetic particle inspec tion has been used for about 70 years /1/. \\i.thout doubt it is for ferromagnetic materials the most sensitive NDT t echnique r ef. to surface de fec t detection and the least sensitive technique as far as disturbing boundary conditions are concerned