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Defect width assessment based on the near-field magnetic flux leakage method

Lookup NU author(s): Xiaotian Chen



This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).


© 2021 by the authors. Licensee MDPI, Basel, Switzerland.Magnetic flux leakage (MFL) testing has been widely used as a non-destructive testing method for various materials. However, it is difficult to separate the influences of the defect geometrical parameters such as depth, width, and length on the received leakage signals. In this paper, a “near-field” MFL method is proposed to quantify defect widths. Both the finite element modelling (FEM) and experimental studies are carried out to investigate the performance of the proposed method. It is found that that the distance between two peaks of the “near-field” MFL is strongly related to the defect width and lift-off value, whereas it is slightly affected by the defect depth. Based on this phenomenon, a defect width assessment relying on the “near-field” MFL method is proposed. Results show that relative judging errors are less than 5%. In addition, the analytical expression of the “near-field” MFL is also developed.

Publication metadata

Author(s): Li E, Chen Y, Chen X, Wu J

Publication type: Article

Publication status: Published

Journal: Sensors

Year: 2021

Volume: 21

Issue: 16

Print publication date: 02/08/2021

Online publication date: 11/08/2021

Acceptance date: 05/08/2021

Date deposited: 25/08/2021

ISSN (electronic): 1424-8220

Publisher: MDPI AG


DOI: 10.3390/s21165424


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