{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,7]],"date-time":"2026-03-07T02:10:19Z","timestamp":1772849419291,"version":"3.50.1"},"reference-count":50,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,3,14]],"date-time":"2023-03-14T00:00:00Z","timestamp":1678752000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"COMPETE 2020","award":["UIDB\/00285\/2020"],"award-info":[{"award-number":["UIDB\/00285\/2020"]}]},{"name":"COMPETE 2020","award":["LA\/P\/0112\/2020"],"award-info":[{"award-number":["LA\/P\/0112\/2020"]}]},{"name":"Portuguese Foundation for Science and Technology (FCT)","award":["UIDB\/00285\/2020"],"award-info":[{"award-number":["UIDB\/00285\/2020"]}]},{"name":"Portuguese Foundation for Science and Technology (FCT)","award":["LA\/P\/0112\/2020"],"award-info":[{"award-number":["LA\/P\/0112\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Metal-coated plastic parts are replacing traditional metallic materials in the automotive industry. Sputtering is an alternative technology that is more environmentally friendly than electrolytic coatings. Most metalized plastic parts are coated with a thin metal layer (~100\u2013200 nm). In this work, the challenge is to achieve thicker films without cracking or without other defects, such as pinholes or pores. Chromium coatings with different thicknesses were deposited onto two different substrates, polycarbonate with and without a base coat, using dc magnetron sputtering in an atmosphere of Ar. Firstly, in order to improve the coating adhesion on the polymer surface, a plasma etching treatment was applied. The coatings were characterized for a wide thickness range from 800 nm to 1600 nm. As the thickness of the coatings increased, there was an increase in the specular reflectivity and roughness of the coatings and changes in morphology due to the columnar growth of the film and a progressive increase in thermal stresses. Furthermore, a decrease in the hardness and the number of pinholes was noticed. The maximum thickness achieved without forming buckling defects was 1400 nm. The tape tests confirmed that every deposited coating showed a good interface adhesion to both polymers.<\/jats:p>","DOI":"10.3390\/ma16062315","type":"journal-article","created":{"date-parts":[[2023,3,14]],"date-time":"2023-03-14T02:33:36Z","timestamp":1678761216000},"page":"2315","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Decorative Chromium Coatings on Polycarbonate Substrate for the Automotive Industry"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8687-5841","authenticated-orcid":false,"given":"Filipa","family":"Ponte","sequence":"first","affiliation":[{"name":"CEMMPRE, Department of Mechanical Engineering, University of Coimbra, Rua Lu\u00eds Reis Santos, 3030-788 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6633-6752","authenticated-orcid":false,"given":"Pooja","family":"Sharma","sequence":"additional","affiliation":[{"name":"CEMMPRE, Department of Mechanical Engineering, University of Coimbra, Rua Lu\u00eds Reis Santos, 3030-788 Coimbra, Portugal"},{"name":"CFUM-UP, Centro de F\u00edsica das Universidades do Minho e do Porto, University of Minho, Campus of Azur\u00e9m, 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9532-0597","authenticated-orcid":false,"given":"Nuno Miguel","family":"Figueiredo","sequence":"additional","affiliation":[{"name":"CEMMPRE, Department of Mechanical Engineering, University of Coimbra, Rua Lu\u00eds Reis Santos, 3030-788 Coimbra, Portugal"}]},{"given":"Jorge","family":"Ferreira","sequence":"additional","affiliation":[{"name":"Engineering Department, KLC\u2014Technical Plastics, 2430-021 Marinha Grande, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3643-4973","authenticated-orcid":false,"given":"Sandra","family":"Carvalho","sequence":"additional","affiliation":[{"name":"CEMMPRE, Department of Mechanical Engineering, University of Coimbra, Rua Lu\u00eds Reis Santos, 3030-788 Coimbra, Portugal"},{"name":"IPN\u2014LED & MAT\u2014Instituto Pedro Nunes, Rua Pedro Nunes, 3030-199 Coimbra, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3807","DOI":"10.1016\/j.matpr.2017.02.278","article-title":"An Overview of Polymeric Materials for Automotive Applications","volume":"4","author":"Patil","year":"2017","journal-title":"Mater. 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