{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,4]],"date-time":"2026-02-04T18:43:45Z","timestamp":1770230625839,"version":"3.49.0"},"reference-count":17,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2012,9,5]],"date-time":"2012-09-05T00:00:00Z","timestamp":1346803200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>GMR sensors are widely used in many industrial segments such as information technology, automotive, automation and production, and safety applications. Each area requires an adaption of the sensor arrangement in terms of size adaption and alignment with respect to the field source involved. This paper deals with an analysis of geometric sensor parameters and the arrangement of GMR sensors providing a design roadmap for non-destructive testing (NDT) applications. For this purpose we use an analytical model simulating the magnetic flux leakage (MFL) distribution of surface breaking defects and investigate the flux leakage signal as a function of various sensor parameters. Our calculations show both the influence of sensor length and height and that when detecting the magnetic flux leakage of \u00b5m sized defects a gradiometer base line of 250 \u00b5m leads to a signal strength loss of less than 10% in comparison with a magnetometer response. To validate the simulation results we finally performed measurements with a GMR magnetometer sensor on a test plate with artificial \u00b5m-range cracks. The differences between simulation and measurement are below 6%. We report on the routes for a GMR gradiometer design as a basis for the fabrication of NDT-adapted sensor arrays. The results are also helpful for the use of GMR in other application when it comes to measure positions, lengths, angles or electrical currents.<\/jats:p>","DOI":"10.3390\/s120912169","type":"journal-article","created":{"date-parts":[[2012,9,5]],"date-time":"2012-09-05T11:40:07Z","timestamp":1346845207000},"page":"12169-12183","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":33,"title":["Routes for GMR-Sensor Design in Non-Destructive Testing"],"prefix":"10.3390","volume":"12","author":[{"given":"Matthias","family":"Pelkner","sequence":"first","affiliation":[{"name":"BAM Federal Institute for Materials Research and Testing, Berlin 12200, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andreas","family":"Neubauer","sequence":"additional","affiliation":[{"name":"BAM Federal Institute for Materials Research and Testing, Berlin 12200, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Verena","family":"Reimund","sequence":"additional","affiliation":[{"name":"BAM Federal Institute for Materials Research and Testing, Berlin 12200, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marc","family":"Kreutzbruck","sequence":"additional","affiliation":[{"name":"BAM Federal Institute for Materials Research and Testing, Berlin 12200, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andreas","family":"Sch\u00fctze","sequence":"additional","affiliation":[{"name":"Laboratory for Measurement Technology, Saarland University, Saarbr\u00fccken 66123, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2012,9,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2472","DOI":"10.1103\/PhysRevLett.61.2472","article-title":"Giant magnetoresistance of (001)Fe\/(001)Cr magnetic superlattices","volume":"66","author":"Baibich","year":"1988","journal-title":"Phys. Rev. Lett."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"4828","DOI":"10.1103\/PhysRevB.39.4828","article-title":"Enhanced magnetoresistance in layered magnetic structures with antiferromagnetic interlayer exchange","volume":"57","author":"Binasch","year":"1989","journal-title":"Phys. Rev. B"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"334","DOI":"10.1016\/S0304-8853(98)00376-X","article-title":"GMR applications","volume":"192","author":"Daughton","year":"1999","journal-title":"J. Magn. Mater."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"107","DOI":"10.1016\/j.pmatsci.2009.07.001","article-title":"Electrodeposited multilayer films with giant magnetoresistance (GMR): Progress and problems","volume":"55","author":"Bakonyi","year":"2010","journal-title":"Prog. Mater. Sci."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"243","DOI":"10.1016\/S0924-4247(03)00176-6","article-title":"Fast magnetic field mapping of permanent magnets with GMR bridge and hall-probe sensors","volume":"106","author":"Christides","year":"2003","journal-title":"Sens. Actuators A: Phys."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"47","DOI":"10.3233\/JAE-2002-427","article-title":"Application of GMR line sensor to detect the magnetic flux distribution for nondestructive testing","volume":"15","author":"Kataoka","year":"2001\/2002","journal-title":"Int. J. Appl. Electromagn. Mech."},{"key":"ref_7","unstructured":"Pelkner, M., Neubauer, A., Blome, M., Reimund, V., Thomas, H.-M., and Kreutzbruck, M. (2011). In Studies in Applied Electromagnetics and Mechanics, IOP Press."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"299","DOI":"10.3233\/JAE-2009-1030","article-title":"Inverse algorithm for electromagnetic wire inspection based on GMR-Sensor arrays","volume":"30","author":"Kreutzbruck","year":"2009","journal-title":"Int. J. Appl. Electromagn. Mech."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1511","DOI":"10.1109\/JSEN.2006.883095","article-title":"Performance of magnetic pulsed-eddy-current system using high dynamic and high linearity improved giant magneto resistance magnetometer","volume":"6","author":"Dolabdjian","year":"2006","journal-title":"IEEE Sens. J."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1016\/j.sna.2010.12.014","article-title":"A GMR-ECT based embedded solution for applications on PCB inspections","volume":"167","author":"Cacciola","year":"2011","journal-title":"Sens. Actuators A: Phys."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"3831","DOI":"10.1109\/20.952754","article-title":"Giant magnetoresistance-based eddy-current sensor","volume":"37","author":"Dogaru","year":"2001","journal-title":"IEEE Trans. Magn."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"141","DOI":"10.1016\/j.ndteint.2009.10.003","article-title":"Classification of pulsed eddy current GMR data on aircraft structures","volume":"43","author":"Kim","year":"2010","journal-title":"NDT&E Int."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"199","DOI":"10.3233\/JAE-2011-1391","article-title":"Fast defect parameter estimation based on magnetic flux leakage measurements with GMR sensors","volume":"37","author":"Reimund","year":"2011","journal-title":"Int. J. Appl. Electromagn. Mech."},{"key":"ref_14","first-page":"50","article-title":"On the calculation of magnetostatic field of surface flaws","volume":"5","author":"Zatsepin","year":"1966","journal-title":"Defektoskopiya"},{"key":"ref_15","first-page":"72","article-title":"Influence of the extension of a defect on the magnitude of its magnetic fields","volume":"8","author":"Shcherbinin","year":"1972","journal-title":"Defektoskopiya"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1016\/0308-9126(86)90134-3","article-title":"New findings in the field of non-destructive magnetic leakage field inspection","volume":"19","author":"Foerster","year":"1986","journal-title":"NDT Int."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"657","DOI":"10.1088\/0022-3727\/19\/4\/018","article-title":"The magnetic leakage field of surface-breaking cracks","volume":"19","author":"Edwards","year":"1986","journal-title":"J. Phys. D: Appl. Phys."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/12\/9\/12169\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:52:10Z","timestamp":1760219530000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/12\/9\/12169"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2012,9,5]]},"references-count":17,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2012,9]]}},"alternative-id":["s120912169"],"URL":"https:\/\/doi.org\/10.3390\/s120912169","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2012,9,5]]}}}