{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,20]],"date-time":"2025-11-20T13:16:45Z","timestamp":1763644605348,"version":"build-2065373602"},"reference-count":29,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,4,5]],"date-time":"2025-04-05T00:00:00Z","timestamp":1743811200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JMMP"],"abstract":"<jats:p>This study presents a simple and innovative design to join a 2 mm thick steel sheet to a 5 mm thick aluminium sheet in a butt configuration. Thickness differences were addressed using support plates, while an aluminium run-on plate was employed to prevent the FSW tool from plunging into the steel. The process produced a unique S-shaped Al\/St interface, the formation mechanism of which is analysed in this study. Scanning electron microscopy (SEM) observations revealed a gradient in the thickness of intermetallic compounds (IMCs) along the joint interface, decreasing from the top to the bottom. This S-shaped interface led to a 150% increase in the ultimate tensile strength (UTS) of the joint. The mechanism underlying this enhancement, attributed to the curved geometry of the interface and its alignment with the loading direction, is discussed in detail. These findings highlight the potential of this approach for improving the performance of dissimilar material joints in lightweight structural applications.<\/jats:p>","DOI":"10.3390\/jmmp9040120","type":"journal-article","created":{"date-parts":[[2025,4,7]],"date-time":"2025-04-07T03:23:07Z","timestamp":1743996187000},"page":"120","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Aluminium\/Steel Joints with Dissimilar Thicknesses: Enhancement of UTS and Ductility Through Making an S-Shaped Interface and a Mixed-Mode Fracture"],"prefix":"10.3390","volume":"9","author":[{"given":"Tiago Oliveira Gon\u00e7alves","family":"Teixeira","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering of the University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"given":"Reza","family":"Beygi","sequence":"additional","affiliation":[{"name":"Department of Materials Engineering and Metallurgy, Faculty of Engineering, Arak University, Arak 38156-8-8349, Iran"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1933-0865","authenticated-orcid":false,"given":"Ricardo Jo\u00e3o Camilo","family":"Carbas","sequence":"additional","affiliation":[{"name":"Institute of Science and Innovation in Mechanical and Industrial Engineering (INEGI), Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"given":"Eduardo Andre Sousa","family":"Marques","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering of the University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-6181-9938","authenticated-orcid":false,"given":"Masih","family":"Bolhasani Hesari","sequence":"additional","affiliation":[{"name":"Department of Materials Engineering and Metallurgy, Faculty of Engineering, Arak University, Arak 38156-8-8349, Iran"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9478-9783","authenticated-orcid":false,"given":"Mohammad Mehdi","family":"Kasaei","sequence":"additional","affiliation":[{"name":"Institute of Science and Innovation in Mechanical and Industrial Engineering (INEGI), Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3272-4591","authenticated-orcid":false,"given":"Lucas Filipe Martins","family":"da Silva","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering of the University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Zhao, H., Zhang, R., and Bin, Z. (2018, January 30\u201331). A Review of Automotive Lightweight Technology. Proceedings of the 2018 International Conference on Mechanical, Electronic, Control and Automation Engineering (MECAE 2018), Qingdao, China.","DOI":"10.2991\/mecae-18.2018.10"},{"key":"ref_2","first-page":"6884","article-title":"Al-steel dissimilar joining: Challenges and opportunities","volume":"62","author":"Kaushik","year":"2022","journal-title":"Mater. Today: Proc."},{"key":"ref_3","first-page":"1126","article-title":"A review on welding techniques: Properties, characterisations and engineering applications","volume":"10","author":"Shravan","year":"2023","journal-title":"Adv. Mater. Process. Technol."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Kumar, N., Yuan, W., and Mishra, R. (2015). Challenges and opportunities for friction stir welding of dissimilar alloys and materials (Chapter 7). 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