{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T06:55:47Z","timestamp":1779346547858,"version":"3.51.4"},"reference-count":35,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2021,8,11]],"date-time":"2021-08-11T00:00:00Z","timestamp":1628640000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["51907131"],"award-info":[{"award-number":["51907131"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["52005510"],"award-info":[{"award-number":["52005510"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2060114"],"award-info":[{"award-number":["2060114"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100012542","name":"Sichuan Province Science and Technology Support Program","doi-asserted-by":"publisher","award":["2020JDRC0060"],"award-info":[{"award-number":["2020JDRC0060"]}],"id":[{"id":"10.13039\/100012542","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100012542","name":"Sichuan Province Science and Technology Support Program","doi-asserted-by":"publisher","award":["20ZDYF2964"],"award-info":[{"award-number":["20ZDYF2964"]}],"id":[{"id":"10.13039\/100012542","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100012542","name":"Sichuan Province Science and Technology Support Program","doi-asserted-by":"publisher","award":["2021YFG0203"],"award-info":[{"award-number":["2021YFG0203"]}],"id":[{"id":"10.13039\/100012542","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010013","name":"Science Foundation for Excellent Youth Scholars of Sichuan University","doi-asserted-by":"publisher","award":["2021SCU12145"],"award-info":[{"award-number":["2021SCU12145"]}],"id":[{"id":"10.13039\/501100010013","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>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 \u201cnear-field\u201d 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 \u201cnear-field\u201d 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 \u201cnear-field\u201d MFL method is proposed. Results show that relative judging errors are less than 5%. In addition, the analytical expression of the \u201cnear-field\u201d MFL is also developed.<\/jats:p>","DOI":"10.3390\/s21165424","type":"journal-article","created":{"date-parts":[[2021,8,11]],"date-time":"2021-08-11T08:35:52Z","timestamp":1628670952000},"page":"5424","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Defect Width Assessment Based on the Near-Field Magnetic Flux Leakage Method"],"prefix":"10.3390","volume":"21","author":[{"given":"Erlong","family":"Li","sequence":"first","affiliation":[{"name":"School of Mechanical Engineering, Sichuan University, Chengdu 610065, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yiming","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Sichuan University, Chengdu 610065, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaotian","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Electrical & Electronic Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jianbo","family":"Wu","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Sichuan University, Chengdu 610065, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Jin, Z., Mohd Noor Sam, M.A.I., Oogane, M., and Ando, Y. 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