{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T16:12:06Z","timestamp":1789661526831,"version":"4.0.1"},"reference-count":35,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2023,11,29]],"date-time":"2023-11-29T00:00:00Z","timestamp":1701216000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper proposes a flexible eddy current TMR (FEC-TMR) sensor to monitor the internal crack of metal joint structures. First, the finite element model of the FEC-TMR sensor is established to analyze the influence of the sensor\u2019s crack identification sensitivity with internal crack propagation at different depths and determine the optimal location and exciting frequency of the sensor. Then, the optimal longitudinal spacing and exciting frequency of the sensor are tested by experiment. The experimental results are consistent with the simulation results, which verify the correctness of the simulation model. Finally, the experiment is carried out for internal cracks of different depths to verify that the sensor can monitor internal cracks, and the crack identification sensitivity gradually decreases with the increase in the depth of the crack from the surface.<\/jats:p>","DOI":"10.3390\/s23239507","type":"journal-article","created":{"date-parts":[[2023,11,30]],"date-time":"2023-11-30T00:34:10Z","timestamp":1701304450000},"page":"9507","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["A Flexible Eddy Current TMR Sensor for Monitoring Internal Fatigue Crack"],"prefix":"10.3390","volume":"23","author":[{"given":"Fei","family":"Yang","sequence":"first","affiliation":[{"name":"Aviation Engineering School, Air Force Engineering University, Xi\u2019an 710038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuting","family":"He","sequence":"additional","affiliation":[{"name":"Aviation Engineering School, Air Force Engineering University, Xi\u2019an 710038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xianghong","family":"Fan","sequence":"additional","affiliation":[{"name":"Aviation Engineering School, Air Force Engineering University, Xi\u2019an 710038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tao","family":"Chen","sequence":"additional","affiliation":[{"name":"Aviation Engineering School, Air Force Engineering University, Xi\u2019an 710038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Teng","family":"Zhang","sequence":"additional","affiliation":[{"name":"Aviation Engineering School, Air Force Engineering University, Xi\u2019an 710038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Binlin","family":"Ma","sequence":"additional","affiliation":[{"name":"Aviation Engineering School, Air Force Engineering University, Xi\u2019an 710038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,11,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8088","DOI":"10.3390\/s150408088","article-title":"Detection of steel fatigue cracks with strain sensing sheets based on large area electronics","volume":"15","author":"Yao","year":"2015","journal-title":"Sensors"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1513","DOI":"10.1109\/JPROC.2016.2573238","article-title":"Strain Sensing Sheets for Structural Health Monitoring Based on Large-Area Electronics and Integrated Circuits","volume":"104","author":"Glisic","year":"2016","journal-title":"Proc. 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