{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:48:48Z","timestamp":1760237328308,"version":"build-2065373602"},"reference-count":24,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2020,4,11]],"date-time":"2020-04-11T00:00:00Z","timestamp":1586563200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002347","name":"Bundesministerium f\u00fcr Bildung und Forschung","doi-asserted-by":"publisher","award":["13N15230"],"award-info":[{"award-number":["13N15230"]}],"id":[{"id":"10.13039\/501100002347","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100006360","name":"Bundesministerium f\u00fcr Wirtschaft und Energie","doi-asserted-by":"publisher","award":["IGF 19579 N"],"award-info":[{"award-number":["IGF 19579 N"]}],"id":[{"id":"10.13039\/501100006360","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Laser-based inspection of trivalent chromium conversion coatings on rough, cold-rolled aluminium substrates is studied from a basic physics perspective by means of angle and wavelength dependent measurements. As a result, we show that the correlation between the scattered laser light and the coating weight of the conversion layer is dominated by the phenomenon of interference. The combined experimental and numerical approach of our study is based on an appropriate layer model which was developed from a set of reference measurements of confocal microscopy, electron microscopy and X-ray photoelectron spectroscopy. The aluminium alloy AA3003 with a trivalent chromium conversion coating serves as an example. Our derived model is capable to reconstruct the reflectance of a laser beam at grazing incidence even for a pronounced surface roughness of      R q  \u2248 300 \u00a0  n m     , for different coating thicknesses less than 70    n      m    corresponding to coating weights between zero and     0.5        g   \/   m         2      and for laser wavelengths from 405    n      m    to 785    n      m   . In our discussion we outline the possibility to transfer the results to other aluminium alloys and\/or other metallic substrates, as well as their potential for industrial applications such as 100% inline-capability, costs, velocity and ruggedness.<\/jats:p>","DOI":"10.3390\/s20082164","type":"journal-article","created":{"date-parts":[[2020,4,13]],"date-time":"2020-04-13T10:41:52Z","timestamp":1586774512000},"page":"2164","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Inspection of Trivalent Chromium Conversion Coatings Using Laser Light: The Unexpected Role of Interference on Cold-Rolled Aluminium"],"prefix":"10.3390","volume":"20","author":[{"given":"Joerg","family":"Rischmueller","sequence":"first","affiliation":[{"name":"Department of Physics, Osnabrueck University, Barbarastrasse 7, 49076 Osnabrueck, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7009-372X","authenticated-orcid":false,"given":"Yannic","family":"Toschke","sequence":"additional","affiliation":[{"name":"Department of Physics, Osnabrueck University, Barbarastrasse 7, 49076 Osnabrueck, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mirco","family":"Imlau","sequence":"additional","affiliation":[{"name":"Department of Physics, Osnabrueck University, Barbarastrasse 7, 49076 Osnabrueck, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mareike","family":"Schlag","sequence":"additional","affiliation":[{"name":"Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM, 28359 Bremen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hauke","family":"Br\u00fcning","sequence":"additional","affiliation":[{"name":"Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM, 28359 Bremen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kai","family":"Brune","sequence":"additional","affiliation":[{"name":"Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM, 28359 Bremen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,4,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1016\/j.buildenv.2018.02.034","article-title":"Characterization and thermal performance evaluation of infrared reflective coatings compatible with historic buildings","volume":"134","author":"Becherini","year":"2018","journal-title":"Build. 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