{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:21:21Z","timestamp":1760059281261,"version":"build-2065373602"},"reference-count":46,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,6,4]],"date-time":"2025-06-04T00:00:00Z","timestamp":1748995200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Research Unit of Digital Services Research Center (CISeD)","doi-asserted-by":"publisher","award":["DOI:10.54499\/UIDB\/05583\/2020","DOI:10.54499\/UIDB\/00151\/2020"],"award-info":[{"award-number":["DOI:10.54499\/UIDB\/05583\/2020","DOI:10.54499\/UIDB\/00151\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, IP\/MCTES through national funds (PIDDAC)","award":["DOI:10.54499\/UIDB\/05583\/2020","DOI:10.54499\/UIDB\/00151\/2020"],"award-info":[{"award-number":["DOI:10.54499\/UIDB\/05583\/2020","DOI:10.54499\/UIDB\/00151\/2020"]}]},{"DOI":"10.13039\/501100001871","name":"Center for Mechanical and Aerospace Science and Technologies (C-MAST-UBI)","doi-asserted-by":"publisher","award":["DOI:10.54499\/UIDB\/05583\/2020","DOI:10.54499\/UIDB\/00151\/2020"],"award-info":[{"award-number":["DOI:10.54499\/UIDB\/05583\/2020","DOI:10.54499\/UIDB\/00151\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Polytechnic Institute of Viseu","award":["DOI:10.54499\/UIDB\/05583\/2020","DOI:10.54499\/UIDB\/00151\/2020"],"award-info":[{"award-number":["DOI:10.54499\/UIDB\/05583\/2020","DOI:10.54499\/UIDB\/00151\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Laser technology is widely regarded as a highly effective method for welding thermoplastic polymers due to its precision, cleanliness, and versatility. This study investigates the effects of laser power and scanning speed on the through-thickness hardness of polypropylene plates, analyzing the heat-affected zone (HAZ) and hardness variations along the depth of the weld bead. Using the Trumpf Trudisk 6602 laser source, multiple polypropylene passes were made with different power levels (200 W and 300 W) and scanning speeds (5, 10, 20, 30, 40, and 50 mm\/s). The results indicate a direct correlation between laser power and scanning speed in the final width and depth of the weld bead. Furthermore, results indicate that higher scanning speeds and lower power promote a more uniform distribution of hardness across the thickness. This study contributes to understanding laser-assisted welding processes in polymeric materials, providing information on the influence of different laser parameters on weld quality and resulting material properties.<\/jats:p>","DOI":"10.3390\/ma18112638","type":"journal-article","created":{"date-parts":[[2025,6,4]],"date-time":"2025-06-04T08:51:04Z","timestamp":1749027064000},"page":"2638","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Effect of Laser Parameters on Through-Thickness Local Hardness of Polypropylene Plates"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6346-5719","authenticated-orcid":false,"given":"Andr\u00e9","family":"Guimar\u00e3es","sequence":"first","affiliation":[{"name":"CISeD\u2014Research Centre for Digital Services, Polytechnic Institute of Viseu, Av. Cor. Jos\u00e9 Maria Vale de Andrade, 3504-510 Viseu, Portugal"},{"name":"CISE\u2014Electomechatronic Systems Research Centre, University of Beira Interior, Rua Marqu\u00eas de \u00c1vila e Bolama, 6201-001 Covilh\u00e3, Portugal"}]},{"given":"Daniel","family":"Gomes","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering and Industrial Management, Polytechnic Institute of Viseu, Av. Cor. Jos\u00e9 Maria Vale de Andrade, 3504-510 Viseu, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6165-8899","authenticated-orcid":false,"given":"Andr\u00e9","family":"Vieira","sequence":"additional","affiliation":[{"name":"CMAST\u2014Centre for Mechanical and Aerospace Science and Technologies, University of Beira Interior, Rua Marqu\u00eas de \u00c1vila e Bolama, 6201-001 Covilh\u00e3, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3499-6681","authenticated-orcid":false,"given":"Serafim M.","family":"Oliveira","sequence":"additional","affiliation":[{"name":"CISeD\u2014Research Centre for Digital Services, Polytechnic Institute of Viseu, Av. Cor. Jos\u00e9 Maria Vale de Andrade, 3504-510 Viseu, Portugal"},{"name":"Department of Mechanical Engineering and Industrial Management, Polytechnic Institute of Viseu, Av. Cor. Jos\u00e9 Maria Vale de Andrade, 3504-510 Viseu, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"126","DOI":"10.30880\/ijie.2024.16.05.011","article-title":"Comparative Analysis of Welding Processes Using Different Thermoplastics","volume":"16","author":"Trindade","year":"2024","journal-title":"Int. J. Integr. Eng."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"589","DOI":"10.1007\/s40194-017-0440-2","article-title":"Laser transmission welding of automotive headlamps without a clamping tool","volume":"61","author":"Lakemeyer","year":"2017","journal-title":"Weld. 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