{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T18:26:05Z","timestamp":1785522365455,"version":"3.56.0"},"reference-count":21,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,1,13]],"date-time":"2022-01-13T00:00:00Z","timestamp":1642032000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Key science and technology projects of Chongqing Education Commission","award":["KJZD-K202101402"],"award-info":[{"award-number":["KJZD-K202101402"]}]},{"name":"Chongqing Natural Science Foundation General Project","award":["cstc2020jcyj-msxmX0783"],"award-info":[{"award-number":["cstc2020jcyj-msxmX0783"]}]},{"name":"Chongqing Natural Science Foundation General Project","award":["cstc2020jcyj-msxmX0109"],"award-info":[{"award-number":["cstc2020jcyj-msxmX0109"]}]},{"DOI":"10.13039\/100012494","name":"Chongqing Municipal Education Commission Foundation","doi-asserted-by":"publisher","award":["KJQN201901442"],"award-info":[{"award-number":["KJQN201901442"]}],"id":[{"id":"10.13039\/100012494","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The pulsed eddy current (PEC) inspection is considered a versatile non-destructive evaluation technique, and it is widely used in metal thickness quantifications for structural health monitoring and target recognition. However, for non-ferromagnetic conductors covered with non-uniform thick insulating layers, there are still deficiencies in the current schemes. The main purpose of this study is to find an effective feature, to measure wall thinning under the large lift-off variations, and further expand application of the PEC technology. Therefore, a novel method named the dynamic apparent time constant (D-ATC) is proposed based on the coil-coupling model. It associates the dynamic behavior of the induced eddy current with the geometric dimensions of the non-ferromagnetic metallic component by the time and amplitude features of the D-ATC curve. Numeral calculations and experiments show that the time signature is immune to large lift-off variations.<\/jats:p>","DOI":"10.3390\/s22020614","type":"journal-article","created":{"date-parts":[[2022,1,14]],"date-time":"2022-01-14T03:14:56Z","timestamp":1642130096000},"page":"614","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["A Novel Pulsed Eddy Current Criterion for Non-Ferromagnetic Metal Thickness Quantifications under Large Liftoff"],"prefix":"10.3390","volume":"22","author":[{"given":"Haowen","family":"Wang","sequence":"first","affiliation":[{"name":"School of Robot Engineering, Yangtze Normal University, Chongqing 408100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiangbo","family":"Huang","sequence":"additional","affiliation":[{"name":"School of Robot Engineering, Yangtze Normal University, Chongqing 408100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Longhuan","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering, Chongqing University, Chongqing 400044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shanqiang","family":"Qin","sequence":"additional","affiliation":[{"name":"School of Robot Engineering, Yangtze Normal University, Chongqing 408100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhihong","family":"Fu","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering, Chongqing University, Chongqing 400044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3965","DOI":"10.1063\/1.1147300","article-title":"Thickness and conductivity of metallic layers from pulsed eddy-current measurements","volume":"67","author":"Tai","year":"1996","journal-title":"Rev. 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