{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T16:28:22Z","timestamp":1783009702157,"version":"3.54.5"},"reference-count":24,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2017,5,12]],"date-time":"2017-05-12T00:00:00Z","timestamp":1494547200000},"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>The low energy transition efficiency of electromagnetic ultrasonic transducer (EMAT) is a common problem in practical application. For the purpose of enhancing the amplitude of the received signal, an improved double-coil bulk wave EMAT is proposed for the thickness measurement of metallic block. This new configuration of magnets consists of a solid cylindrical magnet and a ring-shaped magnet encircling the outer side of the solid cylindrical one. A double-coil was applied instead of a single spiral-coil. Numerical simulations were performed to analyze and optimize the proposed configuration of the EMAT by the 2-D axisymmetric finite element model (FEM). The experiment effectively verifies the rationality of the new configuration and the feasibility of improving the signal strength.<\/jats:p>","DOI":"10.3390\/s17051106","type":"journal-article","created":{"date-parts":[[2017,5,12]],"date-time":"2017-05-12T11:03:53Z","timestamp":1494587033000},"page":"1106","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["An Improved Design of the Spiral-Coil EMAT for Enhancing the Signal Amplitude"],"prefix":"10.3390","volume":"17","author":[{"given":"Xiaojuan","family":"Jia","sequence":"first","affiliation":[{"name":"Institute of Smart Engineering, School of Automation, Chongqing University, Chongqing 400044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qi","family":"Ouyang","sequence":"additional","affiliation":[{"name":"Institute of Smart Engineering, School of Automation, Chongqing University, Chongqing 400044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xinglan","family":"Zhang","sequence":"additional","affiliation":[{"name":"Institute of Smart Engineering, School of Automation, Chongqing University, Chongqing 400044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,5,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"154","DOI":"10.1016\/j.ultras.2015.10.020","article-title":"Simulation of ultrasonic and EMAT arrays FEM and FDTD","volume":"66","author":"Xie","year":"2015","journal-title":"Ultrasonics"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"20","DOI":"10.1016\/j.ndteint.2016.03.002","article-title":"Focused Rayleigh wave EMAT for characterisation of surface-breaking defects","volume":"81","author":"Thring","year":"2016","journal-title":"NDT E Int."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"171","DOI":"10.1016\/j.ndteint.2009.10.009","article-title":"Initial tests for designing a high temperature EMAT with pulsed electromagnet","volume":"43","author":"Dixon","year":"2010","journal-title":"NDT E Int."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Kogia, M., Gan, T.H., Balachandran, W., Livadas, M., Kappatos, V., Szabo, I., Mohimi, A., and Round, A. 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