Multi-gradient eigenvalue-based magnetic barkhausen noise non-destructive testing method

Abstract

The present invention discloses a multi-gradient eigenvalue-based magnetic Barkhausen noise non-destructive testing method; including formulating multi frequency-band division rules according to the magnetic Barkhausen noise testing signals of different frequency-bands within different depth ranges, generated by a ferromagnetic test sample under the cyclic magnetization, to form different testing frequency-bands. One testing frequency-band corresponds to one testing gradient, and the signals of each testing gradient can independently be extracted the testing eigenvalues; thereby, achieving multi-gradient eigenvalue-based non-destructive testing. The new multi-gradient eigenvalue-based magnetic Barkhausen noise non-destructive testing method can increase the number of eigenvalues compared with an original testing method, and can improve the testing accuracy and effectiveness of the original testing method.