{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T18:45:24Z","timestamp":1768416324480,"version":"3.49.0"},"reference-count":24,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2020,11,30]],"date-time":"2020-11-30T00:00:00Z","timestamp":1606694400000},"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":["11902280"],"award-info":[{"award-number":["11902280"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003392","name":"Natural Science Foundation of Fujian Province","doi-asserted-by":"publisher","award":["2018J05094"],"award-info":[{"award-number":["2018J05094"]}],"id":[{"id":"10.13039\/501100003392","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Bolted joints are the primary structures for the load transfer of large-scale structures. It is vital to monitor the process of bolt cracking for enduring structural safety. In this paper, a structural health monitoring technique based on the embedding eddy current sensing film has been proposed to quantify the crack parameters of bolt cracking. Two configurations of the sensing film containing one-dimensional circumferential coil array and two-dimensional coil array are designed and verified to have the ability to identify three crack parameters: the crack angle, the crack depth, and the crack location in the axial direction of the bolt. The finite element method has been employed not only to verify the capacity of the sensing film, but also to investigate the interaction between the crack and the eddy current\/magnetic field. It has been demonstrated that as the crack propagates, the variations of the induced voltage of the sensing coils are influenced by both eddy current effect and magnetic flux leakage, which play different roles in the different periods of the crack propagation. Experiments have been performed to verify the effectiveness and feasibility of the sensing film to quantify three crack parameters in the process of the bolt cracking.<\/jats:p>","DOI":"10.3390\/s20236843","type":"journal-article","created":{"date-parts":[[2020,11,30]],"date-time":"2020-11-30T10:26:12Z","timestamp":1606731972000},"page":"6843","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["An Eddy Current-Based Structural Health Monitoring Technique for Tracking Bolt Cracking"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4272-3552","authenticated-orcid":false,"given":"Hu","family":"Sun","sequence":"first","affiliation":[{"name":"School of Aerospace Engineering, Xiamen University, Xiamen 361005, China"}]},{"given":"Tao","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Aerospace Engineering, Xiamen University, Xiamen 361005, China"}]},{"given":"Dawei","family":"Lin","sequence":"additional","affiliation":[{"name":"School of Aerospace Engineering, Xiamen University, Xiamen 361005, China"}]},{"given":"Yishou","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Aerospace Engineering, Xiamen University, Xiamen 361005, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1189-3046","authenticated-orcid":false,"given":"Xinlin","family":"Qing","sequence":"additional","affiliation":[{"name":"School of Aerospace Engineering, Xiamen University, Xiamen 361005, China"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"243","DOI":"10.1016\/j.tws.2019.02.011","article-title":"Experimental study on fatigue performance of Q460 and Q690 steel bolted connections","volume":"138","author":"Guo","year":"2019","journal-title":"Thin-Walled Struct."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1016\/j.engfailanal.2012.10.015","article-title":"Validation of F-16 Wing Attachment Fitting bolts","volume":"35","author":"Wanhill","year":"2013","journal-title":"Eng. Fail. Anal."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"18","DOI":"10.1016\/S1369-7021(02)01138-0","article-title":"Why aircraft fail","volume":"5","author":"Findlay","year":"2002","journal-title":"Mater. Today"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"209","DOI":"10.1016\/j.engfailanal.2005.10.021","article-title":"Failure analysis of stress corrosion cracking in aircraft bolts","volume":"14","author":"Lee","year":"2007","journal-title":"Eng. Fail. Anal."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Qing, X., Li, W., Wang, Y., and Sun, H. (2019). Piezoelectric Transducer-Based Structural Health Monitoring for Aircraft Applications. Sensors, 19.","DOI":"10.3390\/s19030545"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"3245","DOI":"10.1016\/j.jsv.2011.01.023","article-title":"On the separation of internal and boundary damage in slender bars using longitudinal vibration frequencies and equivalent linearization of damaged bolted joint response","volume":"330","author":"Argatov","year":"2011","journal-title":"J. Sound Vib."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2793","DOI":"10.1016\/j.engstruct.2010.04.048","article-title":"Rupture and damage mechanism analysis of a bolted assembly using coupling techniques between A.E. and D.I.C.","volume":"32","author":"Hoang","year":"2010","journal-title":"Eng. Struct."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"104010","DOI":"10.1088\/1361-665X\/aa6e93","article-title":"A fractal contact theory based model for bolted connection looseness monitoring using piezoceramic transducers","volume":"26","author":"Huo","year":"2017","journal-title":"Smart Mater. Struct."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"125001","DOI":"10.1088\/0964-1726\/23\/12\/125001","article-title":"On-line updating Gaussian mixture model for aircraft wing spar damage evaluation under time-varying boundary condition","volume":"23","author":"Qiu","year":"2014","journal-title":"Smart Mater. Struct."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"130","DOI":"10.1016\/j.ijfatigue.2018.05.014","article-title":"Nonlinear ultrasonic modulation based failure warning for aluminum plates subject to fatigue loading","volume":"114","author":"Kim","year":"2018","journal-title":"Int. J. Fatigue"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"2294","DOI":"10.1177\/1045389X14551435","article-title":"Relative baseline features for impedance-based structural health monitoring","volume":"25","author":"Jung","year":"2014","journal-title":"J. Intell. Mater. Syst. Struct."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"057004","DOI":"10.1088\/1361-665X\/aa6a8e","article-title":"Impedance based bolt pre-load monitoring using piezoceramic smart washer","volume":"26","author":"Huo","year":"2017","journal-title":"Smart Mater. Struct."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"317","DOI":"10.12989\/sss.2009.5.4.317","article-title":"Real time crack detection using mountable comparative vacuum monitoring sensors","volume":"5","author":"Roach","year":"2009","journal-title":"Smart Struct. Syst."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"465","DOI":"10.1007\/s10483-015-1921-9","article-title":"Investigation on behavior of crack penetration\/deflection at interfaces in intelligent coating system","volume":"36","author":"Sun","year":"2015","journal-title":"Appl. Math. Mech."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"85","DOI":"10.1007\/s10921-019-0626-1","article-title":"A Modified Time Reversal Method for Guided Wave Based Bolt Loosening Monitoring in a Lap Joint","volume":"38","author":"Xu","year":"2019","journal-title":"J. Nondestruct. Eval."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"034503","DOI":"10.1115\/1.4026973","article-title":"Detecting Loosening of Bolted Connections in a Pipeline Using Changes in Natural Frequencies","volume":"136","author":"He","year":"2014","journal-title":"J. Vib. Acoust."},{"key":"ref_17","first-page":"603","article-title":"Early prediction of fracturing failure for bolted joints based on enhanced metal magnetic memory","volume":"61","author":"Qiu","year":"2019","journal-title":"Insight Non-Destr. Test. Cond. Monit."},{"key":"ref_18","first-page":"852","article-title":"Eddy Current Sensor Networks for Aircraft Fatigue Monitoring","volume":"61","author":"Goldfine","year":"2003","journal-title":"Mater. Eval."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1177\/1475921711429497","article-title":"A structural health monitoring fastener for tracking fatigue crack growth in bolted metallic joints","volume":"11","author":"Rakow","year":"2011","journal-title":"Struct. Health Monit."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"015018","DOI":"10.1088\/1361-665X\/aae54e","article-title":"A novel eddy current array sensing film for quantitatively monitoring hole-edge crack growth in bolted joints","volume":"28","author":"Sun","year":"2018","journal-title":"Smart Mater. Struct."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Sun, H., Wang, T., Liu, Q., Wang, Y., and Qing, X. (2019). A two-dimensional eddy current array\u2013based sensing film for estimating failure modes and tracking damage growth of bolted joints. Struct. Health Monit., 1475921719843062.","DOI":"10.1177\/1475921719843062"},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Liu, Q., Sun, H., Wang, T., and Qing, X. (2019). On-Site Health Monitoring of Composite Bolted Joint Using Built-In Distributed Eddy Current Sensor Network. Materials, 12.","DOI":"10.3390\/ma12172785"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1016\/0142-1123(84)90005-7","article-title":"A survey of serious aircraft accidents involving fatigue cracking","volume":"6","author":"Campbell","year":"1984","journal-title":"Int. J. Fatigue"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"31036","DOI":"10.3390\/s151229845","article-title":"Theory and Application of Magnetic Flux Leakage Pipeline Detection","volume":"15","author":"Shi","year":"2015","journal-title":"Sensors"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/23\/6843\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T10:39:34Z","timestamp":1760179174000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/23\/6843"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,11,30]]},"references-count":24,"journal-issue":{"issue":"23","published-online":{"date-parts":[[2020,12]]}},"alternative-id":["s20236843"],"URL":"https:\/\/doi.org\/10.3390\/s20236843","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,11,30]]}}}