{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,2]],"date-time":"2026-04-02T15:46:03Z","timestamp":1775144763062,"version":"3.50.1"},"reference-count":79,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2019,5,13]],"date-time":"2019-05-13T00:00:00Z","timestamp":1557705600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100010661","name":"Horizon 2020 Framework Programme","doi-asserted-by":"publisher","award":["722134 \u2013 NDTonAIR"],"award-info":[{"award-number":["722134 \u2013 NDTonAIR"]}],"id":[{"id":"10.13039\/100010661","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Ablative materials are used extensively in the aerospace industry for protection against high thermal stresses and temperatures, an example being glass\/silicone composites. The extreme conditions faced and the cost-risk related to the production\/operating stage of such high-tech materials indicate the importance of detecting any anomaly or defect arising from the manufacturing process. In this paper, two different non-destructive testing techniques, namely active thermography and ultrasonic testing, have been used to detect a delamination in a glass\/silicone composite. It is shown that a frequency modulated chirp signal and pulse-compression can successfully be used in active thermography for detecting such a delamination. Moreover, the same type of input signal and post-processing can be used to generate an image using air-coupled ultrasound, and an interesting comparison between the two can be made to further characterise the defect.<\/jats:p>","DOI":"10.3390\/s19092198","type":"journal-article","created":{"date-parts":[[2019,5,13]],"date-time":"2019-05-13T05:35:39Z","timestamp":1557725739000},"page":"2198","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":29,"title":["Delamination Detection in Polymeric Ablative Materials Using Pulse-Compression Thermography and Air-Coupled Ultrasound"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7283-2004","authenticated-orcid":false,"given":"Stefano","family":"Laureti","sequence":"first","affiliation":[{"name":"Department of Engineering, University of Perugia, Polo Scientifico Didattico di Terni, Strada di Pentima 4, 05100 Terni, Italy"}]},{"given":"Muhammad","family":"Khalid Rizwan","sequence":"additional","affiliation":[{"name":"Department of Engineering, University of Perugia, Polo Scientifico Didattico di Terni, Strada di Pentima 4, 05100 Terni, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8042-2339","authenticated-orcid":false,"given":"Hamed","family":"Malekmohammadi","sequence":"additional","affiliation":[{"name":"Department of Engineering, University of Perugia, Polo Scientifico Didattico di Terni, Strada di Pentima 4, 05100 Terni, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4094-7621","authenticated-orcid":false,"given":"Pietro","family":"Burrascano","sequence":"additional","affiliation":[{"name":"Department of Engineering, University of Perugia, Polo Scientifico Didattico di Terni, Strada di Pentima 4, 05100 Terni, Italy"}]},{"given":"Maurizio","family":"Natali","sequence":"additional","affiliation":[{"name":"Department of Civil and Environmental Engineering, University of Perugia, Polo Scientifico Didattico di Terni, Strada di Pentima 4, 05100 Terni, Italy"}]},{"given":"Luigi","family":"Torre","sequence":"additional","affiliation":[{"name":"Department of Civil and Environmental Engineering, University of Perugia, Polo Scientifico Didattico di Terni, Strada di Pentima 4, 05100 Terni, Italy"}]},{"given":"Marco","family":"Rallini","sequence":"additional","affiliation":[{"name":"Department of Civil and Environmental Engineering, University of Perugia, Polo Scientifico Didattico di Terni, Strada di Pentima 4, 05100 Terni, Italy"}]},{"given":"Ivan","family":"Puri","sequence":"additional","affiliation":[{"name":"Department of Civil and Environmental Engineering, University of Perugia, Polo Scientifico Didattico di Terni, Strada di Pentima 4, 05100 Terni, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1121-531X","authenticated-orcid":false,"given":"David","family":"Hutchins","sequence":"additional","affiliation":[{"name":"School of Engineering, University of Warwick, Library Road, Coventry CV4 7AL, UK"}]},{"given":"Marco","family":"Ricci","sequence":"additional","affiliation":[{"name":"Department of Informatics, Modeling, Electronics and System Engineering, University of Calabria, 87036 Rende, Italy"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,13]]},"reference":[{"key":"ref_1","unstructured":"D\u2019Aelio, G.F., and Parker, J.A. 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