The feasibility of MFL inspection for omni-directional defects under a unidirectional magnetization

Issue title: Selected Papers from the 14th International Symposium on Applied Electromagnetics and Mechanics (ISEM 2009), Part II

Article type: Research Article

Authors: Sun, Yanhua^a | Kang, Yihua^{a; *}

Affiliations: [a] State Key Lab of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430074, China

Correspondence: [*] Corresponding author. E-mail: yhkang@263.net

Abstract: For the drawbacks of present MFL (magnetic flux leakage) testing of omni-directional defects using multidirectional magnetization, a new method of MFL inspection for omni-direction defects under a unidirectional magnetization is proposed. Then, its feasibility is verified by simulations and experiments, leading to a breakthrough of the conventional MFL theory which argues that there is little MFL produced by the defects parallel or nearly parallel to the magnetization direction. Additionally, a method for ensuring a uniform evaluation for the defects with same sizes but different directions is also presented. Finally, some good application cases of the proposed technology were shown.

Keywords: MFL (magnetic flux leakage), Unidirectional magnetization, Axial magnetization, Omni-directional defects

DOI: 10.3233/JAE-2010-1202

Journal: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 3-4, pp. 919-925, 2010