A permanent magnetic perturbation testing sensor

A new PMP (permanent magnetic perturbation) testing sensor for NDT (nondestructive testing) was proposed for the first time based on the analysis of magnetic perturbation mechanism and PMP principle. Afterwards, the proposed PMP sensor was developed and its relevant structural parameter for design was analyzed by experiments. The comparisons among PMP, MFL (magnetic flux leakage) and ECT (eddy-current testing) sensor were carried out, which suggest that PMP is a new method. Finally, some practical engineering application cases of PMP sensor were presented, which further indicate that the proposed PMP sensor is of great practical value and the potential of wide industrial applications as a supplement of conventional NDT methods.