{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T15:19:31Z","timestamp":1768490371726,"version":"3.49.0"},"reference-count":44,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2025,7,30]],"date-time":"2025-07-30T00:00:00Z","timestamp":1753833600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>This study investigates the friction stir joining of AA6082-T6 aluminum alloy and Noryl GFN2 polymer in a buttstrap configuration, targeting the development of lightweight cylindrical-shaped structures where the polymer provides thermal, chemical, and electrical insulation, while the aluminum ensures mechanical integrity. A parametric analysis was carried out to assess the ability to produce friction stir buttstrap composite panels in a single processing step and assess the resulting tensile and flexural behavior. To that end, travel and rotating speeds ranging from 2150 to 2250 rpm, and 100 to 140 mm\/min, respectively, were employed while keeping plunge depth and the tilt angle constant. A total of nine composite joints were successfully produced and subsequently subjected to both tensile and four-point bending tests. The tensile and flexural strength results ranged from 80 to 139 MPa, and 39 to 47 MPa, respectively. Moreover, the microstructural examination revealed that all joints exhibited a defect within the joining region and its size and shape had a significant effect on tensile strength, whereas the flexural strength was less affected with more uniform results. The joining region was also characterized by a decrease in hardness, particularly in the pin-affected region on the aluminum end of the joint, exhibiting a W-shaped pattern. Contrarily, on the polymeric end of the joining region, no significant change in hardness was observed.<\/jats:p>","DOI":"10.3390\/polym17152084","type":"journal-article","created":{"date-parts":[[2025,7,30]],"date-time":"2025-07-30T10:55:37Z","timestamp":1753872937000},"page":"2084","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Tensile and Flexural Behavior of Metal\u2013Polymer Friction Stir Buttstrap Composite Panels"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8165-5946","authenticated-orcid":false,"given":"Arm\u00e9nio N.","family":"Correia","sequence":"first","affiliation":[{"name":"Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0587-3041","authenticated-orcid":false,"given":"Daniel F. O.","family":"Braga","sequence":"additional","affiliation":[{"name":"INEGI, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 400, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5955-8418","authenticated-orcid":false,"given":"Ricardo","family":"Baptista","sequence":"additional","affiliation":[{"name":"UnIRE, ISEL\u2014Instituto Instituto Superior de Engenharia de Lisboa, Instituto Polit\u00e9cnico de Lisboa, Rua Conselheiro Em\u00eddio Navarro, 1959-007 Lisboa, Portugal"}]},{"given":"Virg\u00ednia","family":"Infante","sequence":"additional","affiliation":[{"name":"LAETA, IDMEC, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"100652","DOI":"10.1016\/j.sftr.2025.100652","article-title":"Evaluating the European transportation sector via energy and climate change mitigation perspectives","volume":"9","year":"2025","journal-title":"Sustain. Futures"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"139250","DOI":"10.1016\/j.jclepro.2023.139250","article-title":"Driving towards a sustainable future: Transport sector innovation, climate change and social welfare","volume":"427","author":"Khurshid","year":"2023","journal-title":"J. Clean. Prod."},{"key":"ref_3","unstructured":"EEA (2022). Decarbonising Road Transport\u2014The Role of Vehicles, Fuels and Transport Demand."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"28217","DOI":"10.1016\/j.ijhydene.2020.07.256","article-title":"Is the H2 economy realizable in the foreseeable future? Part III: H2 usage technologies, applications, and challenges and opportunities","volume":"45","author":"Nazir","year":"2020","journal-title":"Int. J. Hydrogen Energy"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Chakraborty, S., Dash, S.K., Elavarasan, R.M., Kaur, A., Elangovan, D., Meraj, S.T., Kasinathan, P., and Said, Z. (2022). Hydrogen Energy as Future of Sustainable Mobility. Front. Energy Res., 10.","DOI":"10.3389\/fenrg.2022.893475"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"112475","DOI":"10.1016\/j.rser.2022.112475","article-title":"When, where and how can the electrification of passenger cars reduce greenhouse gas emissions?","volume":"162","author":"Sacchi","year":"2022","journal-title":"Renew. Sustain. Energy Rev."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"105652","DOI":"10.1016\/j.engfailanal.2021.105652","article-title":"Review on dissimilar structures joints failure","volume":"129","author":"Correia","year":"2021","journal-title":"Eng. Fail. Anal."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Pereira, M.A.R., Amaro, A.M., Reis, P.N.B., and Loureiro, A. (2021). Effect of Friction Stir Welding Techniques and Parameters on Polymers Joint Efficiency-A Critical Review. Polymers, 13.","DOI":"10.3390\/polym13132056"},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Kumar, N., Yuan, W., and Mishra, R.S. (2015). Friction Stir Welding of Dissimilar Alloys and Materials, Butterworth-Heinemann. Friction Stir Welding and Processing.","DOI":"10.1016\/B978-0-12-802418-8.00004-7"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"303","DOI":"10.1177\/0892705704045187","article-title":"Fusion Bonding\/Welding of Thermoplastic Composites","volume":"17","author":"Yousefpour","year":"2004","journal-title":"J. Thermoplast. Compos. Mater."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Correia, A.N., Gaspar, B.M., Cipriano, G., Braga, D.F.O., Baptista, R., and Infante, V. (2024). Thermo-Mechanical Characterization of Metal\u2013Polymer Friction Stir Composite Joints\u2014A Full Factorial Design of Experiments. Polymers, 16.","DOI":"10.3390\/polym16050602"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"108805","DOI":"10.1016\/j.engfailanal.2024.108805","article-title":"Experimental and numerical investigation on failure behaviour of aluminum-polymer friction stir composite joints","volume":"165","author":"Correia","year":"2024","journal-title":"Eng. Fail. Anal."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1461","DOI":"10.1002\/pen.21424","article-title":"Joining of polymers and polymer-metal hybrid structures: Recent developments and trends","volume":"49","year":"2009","journal-title":"Polym. Eng. Sci."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"379","DOI":"10.1016\/j.jmatprotec.2017.08.005","article-title":"Improving energy efficiency in friction assisted joining of metals and polymers","volume":"250","author":"Lambiase","year":"2017","journal-title":"J. Mater. Process. Technol."},{"key":"ref_15","unstructured":"Thomas, W.M., Dolby, R.E., and Thomas, W.M. (2002, January 15\u201319). Friction Stir Welding Developments. Proceedings of the 6th International Conference on Trends in Welding Research, Pine Mountain, GA, USA."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"10","DOI":"10.1007\/BF03266403","article-title":"Friction Stir Welding Tools and Developments","volume":"47","author":"Thomas","year":"2003","journal-title":"Weld. World"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Ahmed, M.M.Z., El-Sayed Seleman, M.M., Fydrych, D., and Cam, G. (2023). Friction Stir Welding of Aluminum in the Aerospace Industry: The Current Progress and State-of-the-Art Review. Materials, 16.","DOI":"10.3390\/ma16082971"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Sambasivam, S., Gupta, N., Jassim, A.S., Pratap Singh, D., Kumar, S., Mohan Giri, J., and Gupta, M. (2023). A review paper of FSW on dissimilar materials using aluminum. Mater. Today Proc.","DOI":"10.1016\/j.matpr.2023.03.304"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Barakat, A.A., Darras, B.M., Nazzal, M.A., and Ahmed, A.A. (2022). A Comprehensive Technical Review of the Friction Stir Welding of Metal-to-Polymer Hybrid Structures. Polymers, 15.","DOI":"10.3390\/polym15010220"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"118116","DOI":"10.1016\/j.jmatprotec.2023.118116","article-title":"Material flow in friction stir welding: A review","volume":"320","author":"Ambrosio","year":"2023","journal-title":"J. Mater. Process. Technol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"55","DOI":"10.1016\/j.matpr.2022.01.457","article-title":"Friction based solid state welding\u2014A review","volume":"62","author":"Parvez","year":"2022","journal-title":"Mater. Today Proc."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"107155","DOI":"10.1016\/j.engfailanal.2023.107155","article-title":"Effects of processing temperature on failure mechanisms of dissimilar aluminum-to-polymer joints produced by friction stir welding","volume":"146","author":"Correia","year":"2023","journal-title":"Eng. Fail. Anal."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"108941","DOI":"10.1016\/j.compositesb.2021.108941","article-title":"Achieving high-quality metal to polymer-matrix composites joint via top-thermic solid-state lap joining","volume":"219","author":"Li","year":"2021","journal-title":"Compos. Part B Eng."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"222","DOI":"10.1179\/1362171814Y.0000000276","article-title":"Dissimilar joining between aluminium alloy (AA 6111) and thermoplastics using friction stir welding","volume":"20","author":"Ratanathavorn","year":"2015","journal-title":"Sci. Technol. Weld. Join."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"148","DOI":"10.1016\/j.jmatprotec.2018.02.043","article-title":"Joining of aluminum alloy and polymer via friction stir lap welding","volume":"257","author":"Huang","year":"2018","journal-title":"J. Mater. Process. Technol."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Correia, A.N., Santos, P.A.M., Braga, D.F.O., Baptista, R., and Infante, V. (2023). Effects of Friction Stir Welding Process Control and Tool Penetration on Mechanical Strength and Morphology of Dissimilar Aluminum-to-Polymer Joints. J. Manuf. Mater. Process., 7.","DOI":"10.3390\/jmmp7030106"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"3313","DOI":"10.1007\/s10853-005-2709-x","article-title":"Effects of double passes of the tool on friction stir welding of polyethylene","volume":"40","author":"Arici","year":"2005","journal-title":"J. Mater. Sci."},{"key":"ref_28","first-page":"73","article-title":"Estimating and optimizing the flexural strength of bonding welded polypropylene sheets by friction-stir welding method","volume":"235","author":"Mirabzadeh","year":"2020","journal-title":"Proc. Inst. Mech. Eng. Part L J. Mater. Des. Appl."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1007\/s40194-017-0517-y","article-title":"Effects of processing parameters on the characteristics of dissimilar friction-stir-welded joints between AA5058 aluminum alloy and PMMA polymer","volume":"62","author":"Derazkola","year":"2017","journal-title":"Weld. World"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Correia, A.N., Coelho, R.J., Braga, D.F.O., Guedes, M., Baptista, R., and Infante, V. (2025). Effect of Service Temperature on the Mechanical and Fatigue Behaviour of Metal-Polymer Friction Stir Composite Joints. Polymers, 17.","DOI":"10.3390\/polym17101366"},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Peters, E.N. (2017). Poly(phenylene ether) Based Amphiphilic Block Copolymers. Polymers, 9.","DOI":"10.3390\/polym9090433"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"477","DOI":"10.1002\/pen.760250809","article-title":"Polyphenylene ethers and their alloys","volume":"25","author":"Warren","year":"1985","journal-title":"Polym. Eng. Sci."},{"key":"ref_33","unstructured":"BV, S.I.P.I. (Noryl resin\u2014Modified PPE-PS Americas, 2007). Noryl resin\u2014Modified PPE-PS Americas."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1413","DOI":"10.1080\/15376494.2022.2137886","article-title":"Mechanical behavior of friction stir butt welded joints under different loading and temperature conditions","volume":"31","author":"Pinto","year":"2022","journal-title":"Mech. Adv. Mater. Struct."},{"key":"ref_35","unstructured":"Jones, R.M. (1999). Mechanics of Composite Materials, CRC Press. [2nd ed.]."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.mser.2005.07.001","article-title":"Friction stir welding and processing","volume":"50","author":"Mishra","year":"2005","journal-title":"Mater. Sci. Eng. R Rep."},{"key":"ref_37","first-page":"231","article-title":"Investigation of tool forces, weld bead micro-hardness and surface roughness during friction stir welding of Aluminium 6063 alloy","volume":"8","author":"Chinchanikar","year":"2022","journal-title":"Adv. Mater. Process. Technol."},{"key":"ref_38","unstructured":"Hibbeler, R.C. (2018). Mechanics of Materials, Pearson."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"4021","DOI":"10.1016\/j.jmrt.2021.10.028","article-title":"Effect of incomplete penetration defects on mechanical and fatigue properties of friction-stir-welded 6802-T6 joint","volume":"15","author":"Xu","year":"2021","journal-title":"J. Mater. Res. Technol."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"1097","DOI":"10.1007\/s00170-024-13107-8","article-title":"Influence of welding speed on the root defects formation and mechanical properties of FSWed 6082-T6 Al alloy joint","volume":"131","author":"Dai","year":"2024","journal-title":"Int. J. Adv. Manuf. Technol."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"105979","DOI":"10.1016\/j.ijfatigue.2020.105979","article-title":"Mechanical properties of 2024-T3 AlClad aluminum FSW lap joints and impact of surface preparation","volume":"143","author":"Robitaille","year":"2021","journal-title":"Int. J. Fatigue"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"310","DOI":"10.1016\/j.ijfatigue.2015.06.020","article-title":"Study of the fatigue behaviour of dissimilar aluminium joints produced by friction stir welding","volume":"82","author":"Infante","year":"2016","journal-title":"Int. J. Fatigue"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"719","DOI":"10.1007\/s00170-015-6866-z","article-title":"Analysis of AA 6082-T6 welds strength mismatch: Stress versus hardness relationships","volume":"79","author":"Costa","year":"2015","journal-title":"Int. J. Adv. Manuf. Technol."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"100011","DOI":"10.1016\/j.jajp.2020.100011","article-title":"Investigation of mechanical properties of AA6082-T6\/AA6063-T6 friction stir lap welds","volume":"1","author":"Baratzadeh","year":"2020","journal-title":"J. Adv. Join. Process."}],"container-title":["Polymers"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4360\/17\/15\/2084\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T18:18:44Z","timestamp":1760033924000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4360\/17\/15\/2084"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,7,30]]},"references-count":44,"journal-issue":{"issue":"15","published-online":{"date-parts":[[2025,8]]}},"alternative-id":["polym17152084"],"URL":"https:\/\/doi.org\/10.3390\/polym17152084","relation":{},"ISSN":["2073-4360"],"issn-type":[{"value":"2073-4360","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,7,30]]}}}