{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T16:58:06Z","timestamp":1792083486265,"version":"4.4.0"},"reference-count":56,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,4,12]],"date-time":"2023-04-12T00:00:00Z","timestamp":1681257600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Ultrasonic metal welding (USMW) is widely used in assembling lithium-ion (Li-ion) battery packs due to its advantages in joining dissimilar and conductive materials in the solid state. However, the welding process and mechanisms are not yet clearly understood. In this study, dissimilar joints of aluminum alloy EN AW 1050 to copper alloy EN CW 008A were welded by USMW to simulate the tab-to-bus bar interconnects for Li-ion battery assembly. Qualitative and quantitative investigations were carried out on plastic deformation, microstructural evolution, and the correlated mechanical properties. During USMW, the plastic deformation concentrated on the Al side. The thickness of Al was reduced by more than 30%; complex dynamic recrystallization and grain growth occurred near the weld interface. The mechanical performance of the Al\/Cu joint was evaluated with the tensile shear test. The failure load gradually increased until a welding duration of 400 ms, and then remained almost constant. The obtained results showed that the mechanical properties were greatly influenced by plastic deformation and microstructure evolution, which provides guidance for improving the weld quality and the process in general.<\/jats:p>","DOI":"10.3390\/ma16083033","type":"journal-article","created":{"date-parts":[[2023,4,12]],"date-time":"2023-04-12T02:08:11Z","timestamp":1681265291000},"page":"3033","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["In-Depth Evaluation of Ultrasonically Welded Al\/Cu Joint: Plastic Deformation, Microstructural Evolution, and Correlation with Mechanical Properties"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0471-7426","authenticated-orcid":false,"given":"Junqi","family":"Li","sequence":"first","affiliation":[{"name":"Walter-and-Ingeborg-Herrmann Chair for Power Ultrasonics and Engineering of Functional Materials, Department of Sustainable Systems Engineering (INATECH), Faculty of Engineering, University of Freiburg, 79110 Freiburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Johannes","family":"Zillner","sequence":"additional","affiliation":[{"name":"Walter-and-Ingeborg-Herrmann Chair for Power Ultrasonics and Engineering of Functional Materials, Department of Sustainable Systems Engineering (INATECH), Faculty of Engineering, University of Freiburg, 79110 Freiburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Frank","family":"Balle","sequence":"additional","affiliation":[{"name":"Walter-and-Ingeborg-Herrmann Chair for Power Ultrasonics and Engineering of Functional Materials, Department of Sustainable Systems Engineering (INATECH), Faculty of Engineering, University of Freiburg, 79110 Freiburg, Germany"},{"name":"Freiburg Materials Research Center (FMF), 79104 Freiburg, Germany"},{"name":"Fraunhofer Institute for High-Speed Dynamics (EMI), 79104 Freiburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"505","DOI":"10.1016\/j.jpowsour.2004.11.007","article-title":"Requirements for Future Automotive Batteries\u2014A Snapshot","volume":"144","author":"Karden","year":"2005","journal-title":"J. Power Sources"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1186","DOI":"10.1016\/j.jpowsour.2005.11.086","article-title":"Economic and Environmental Comparison of Conventional, Hybrid, Electric and Hydrogen Fuel Cell Vehicles","volume":"159","author":"Granovskii","year":"2006","journal-title":"J. Power Sources"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"225","DOI":"10.1021\/es9905290","article-title":"Environmental Implications of Alternative-Fueled Automobiles: Air Quality and Greenhouse Gas Tradeoffs","volume":"34","author":"Maclean","year":"2000","journal-title":"Environ. Sci. Technol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1016\/j.enconman.2012.02.023","article-title":"A Sustainability Assessment of Electric Vehicles as a Personal Mobility System","volume":"61","author":"Faria","year":"2012","journal-title":"Energy Convers. Manag."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Das, A., Li, D., Williams, D., and Greenwood, D. (2018). Joining Technologies for Automotive Battery Systems Manufacturing. World Electr. Veh. J., 9.","DOI":"10.3390\/wevj9020022"},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Lee, S.S., Kim, T.H., Hu, S.J., Cai, W.W., and Abell, J.A. (2010, January 12\u201315). Joining Technologies for Automotive Lithium-Ion Battery Manufacturing: A Review. Proceedings of the International Manufacturing Science and Engineering Conference, Erie, PA, USA.","DOI":"10.1115\/MSEC2010-34168"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Warner, J. (2014). Lithium-Ion Battery Packs for EVs, Elsevier.","DOI":"10.1016\/B978-0-444-59513-3.00007-8"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"021004","DOI":"10.1115\/1.4023364","article-title":"Characterization of Joint Quality in Ultrasonic Welding of Battery Tabs","volume":"135","author":"Lee","year":"2013","journal-title":"J. Manuf. Sci. Eng."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"141","DOI":"10.1016\/j.jmatprotec.2016.11.004","article-title":"Mechanical Performance and Electrical Resistance of Ultrasonic Welded Multiple Cu-Al Layers","volume":"241","author":"Shin","year":"2017","journal-title":"J. Mater. Process. Technol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1007\/s00170-013-5446-3","article-title":"Parasitic Vibration Attenuation in Ultrasonic Welding of Battery Tabs","volume":"71","author":"Lee","year":"2014","journal-title":"Int. J. Adv. Manuf. Technol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"100017","DOI":"10.1016\/j.jajp.2020.100017","article-title":"Automotive Battery Pack Manufacturing\u2014A Review of Battery to Tab Joining","volume":"1","author":"Zwicker","year":"2020","journal-title":"J. Adv. Join. Process."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"54","DOI":"10.1007\/s40430-018-1542-5","article-title":"Weldability and Shear Strength Feasibility Study for Automotive Electric Vehicle Battery Tab Interconnects","volume":"41","author":"Das","year":"2019","journal-title":"J. Brazilian Soc. Mech. Sci. Eng."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1016\/j.est.2015.04.001","article-title":"Welding Techniques for Battery Cells and Resulting Electrical Contact Resistances","volume":"1","author":"Brand","year":"2015","journal-title":"J. Energy Storage"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"5168","DOI":"10.1016\/j.matpr.2020.02.873","article-title":"Ultrasonic Spot Welding of Al-Cu Sheets: A Comprehensive Study","volume":"33","author":"Pati","year":"2020","journal-title":"Mater. Today Proc."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"031012","DOI":"10.1115\/1.4041182","article-title":"A State-of-the-Art Review on Solid-State Metal Joining","volume":"141","author":"Cai","year":"2019","journal-title":"J. Manuf. Sci. Eng. Trans. ASME"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"96","DOI":"10.1016\/j.jmapro.2018.04.020","article-title":"Ultrasonic Spot Welding of Aluminum-Copper Dissimilar Metals: A Study on Joint Strength by Experimentation and Machine Learning Techniques","volume":"33","author":"Satpathy","year":"2018","journal-title":"J. Manuf. Process."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"354","DOI":"10.1179\/1362171813Y.0000000114","article-title":"Effect of Welding Energy on Interface Zone of Al\u2013Cu Ultrasonic Welded Joint","volume":"18","author":"Zhao","year":"2013","journal-title":"Sci. Technol. Weld. Join."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Liu, J., Cao, B., and Yang, J. (2017). Effects of Vibration Amplitude on Microstructure Evolution and Mechanical Strength of Ultrasonic Spot Welded Cu\/Al Joints. Metals., 7.","DOI":"10.3390\/met7110471"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Liu, G., Hu, X., Fu, Y., and Li, Y. (2017). Microstructure and Mechanical Properties of Ultrasonic Welded Joint of 1060 Aluminum Alloy and T2 Pure Copper. Metals., 7.","DOI":"10.3390\/met7090361"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1080\/02286203.2017.1395198","article-title":"Ultrasonic Spot Welding of Al\u2013Cu Dissimilar Metals: A Study on Parametric Influence and Thermo-Mechanical Simulation","volume":"38","author":"Satpathy","year":"2018","journal-title":"Int. J. Model. Simul."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"443","DOI":"10.1016\/j.jmapro.2017.01.001","article-title":"Mechanical Performance and Metallurgical Characterization of Ultrasonically Welded Dissimilar Joints","volume":"25","author":"Satpathy","year":"2017","journal-title":"J. Manuf. Process."},{"key":"ref_22","first-page":"55","article-title":"Experimental Investigations on Optimization of Ultrasonic Welding Parameters for Copper To Brass Joints Using Response Surface Method and Genetic Algorithm","volume":"I","author":"Elangovan","year":"2015","journal-title":"Int. J. Adv. Eng. Res."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"7411","DOI":"10.3934\/mbe.2020379","article-title":"Multi-Objective Optimization of Peel and Shear Strengths in Ultrasonic Metal Welding Using Machine Learning-Based Response Surface Methodology","volume":"17","author":"Meng","year":"2020","journal-title":"Math. Biosci. Eng."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"26","DOI":"10.1016\/j.jmapro.2020.01.047","article-title":"Applications of Ultrasonic Testing and Machine Learning Methods to Predict the Static & Fatigue Behavior of Spot-Welded Joints","volume":"52","author":"Amiri","year":"2020","journal-title":"J. Manuf. Process."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1125","DOI":"10.1007\/s10845-022-01911-6","article-title":"Multi-Objective Optimisation of Ultrasonically Welded Dissimilar Joints through Machine Learning","volume":"33","author":"Mongan","year":"2022","journal-title":"J. Intell. Manuf."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1016\/j.cirp.2011.03.016","article-title":"Process Robustness of Single Lap Ultrasonic Welding of Thin, Dissimilar Materials","volume":"60","author":"Yum","year":"2011","journal-title":"CIRP Ann. Manuf. Technol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"881","DOI":"10.1007\/s00170-018-2936-3","article-title":"Process Robustness and Strength Analysis of Multi-Layered Dissimilar Joints Using Ultrasonic Metal Welding","volume":"101","author":"Das","year":"2019","journal-title":"Int. J. Adv. Manuf. Technol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"309","DOI":"10.1007\/s10704-005-6036-7","article-title":"Determining Node-I Cohesive Parameters for Nugget Fracture in Ultrasonic Spot Welds","volume":"136","author":"Zhou","year":"2005","journal-title":"Int. J. Fract."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Bao, N., and Zhao, R. (2018, January 10\u201312). Design Optimization of Battery Holder for Electric Vehicle. Proceedings of the 2018 6th International Conference on Mechanical, Automotive and Materials Engineering (CMAME), Hong Kong, China.","DOI":"10.1109\/CMAME.2018.8592441"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"833","DOI":"10.1016\/S0378-7753(03)00281-7","article-title":"Battery Dimensional Changes Occurring during Charge\/Discharge Cycles\u2014Thin Rectangular Lithium Ion and Polymer Cells","volume":"119\u2013121","author":"Lee","year":"2003","journal-title":"J. Power Sources"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"041011","DOI":"10.1115\/1.4026990","article-title":"Dynamic Stress Analysis of Battery Tabs Under Ultrasonic Welding","volume":"136","author":"Kang","year":"2014","journal-title":"J. Manuf. Sci. Eng."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"051003","DOI":"10.1115\/1.4027878","article-title":"A Fatigue Life Study of Ultrasonically Welded Lithium-Ion Battery Tab Joints Based on Electrical Resistance","volume":"136","author":"Zhao","year":"2014","journal-title":"J. Manuf. Sci. Eng."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"307","DOI":"10.1016\/j.jmapro.2019.04.006","article-title":"Microstructure Evolution and Mechanical Properties of Al\/Cu Ultrasonic Spot Welded Joints during Thermal Processing","volume":"41","author":"Ao","year":"2019","journal-title":"J. Manuf. Process."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Braunovic, M., Myshkin, N.K., and Konchits, V.V. (2017). Electrical Contacts, Fundamentals, Applications and Technology, Taylor & Francis.","DOI":"10.1201\/9780849391088"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"431","DOI":"10.1016\/j.jmatprotec.2016.01.006","article-title":"In-Situ Measurement of Relative Motion during Ultrasonic Spot Welding of Aluminum Alloy Using Photonic Doppler Velocimetry","volume":"231","author":"Lu","year":"2016","journal-title":"J. Mater. Process. Technol."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1179\/1362171812Y.0000000066","article-title":"Analysis for Relative Motion in Ultrasonic Welding of Aluminium Sheet","volume":"18","author":"Sasaki","year":"2013","journal-title":"Sci. Technol. Weld. Join."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"208","DOI":"10.1080\/13621718.2016.1218601","article-title":"Study of Plastic Deformation and Interface Friction Process for Ultrasonic Welding","volume":"22","author":"Chen","year":"2017","journal-title":"Sci. Technol. Weld. Join."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"031016","DOI":"10.1115\/1.4029787","article-title":"Analysis of Weld Formation in Multilayer Ultrasonic Metal Welding Using High-Speed Images","volume":"137","author":"Lee","year":"2015","journal-title":"J. Manuf. Sci. Eng."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"4915","DOI":"10.1016\/j.jmatprotec.2009.01.014","article-title":"Bond Formation and Fiber Embedment during Ultrasonic Consolidation","volume":"209","author":"Yang","year":"2009","journal-title":"J. Mater. Process. Technol."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1016\/j.jmapro.2015.06.002","article-title":"Microstructure, Welding Mechanism, and Failure of Al\/Cu Ultrasonic Welds","volume":"20","author":"Wu","year":"2015","journal-title":"J. Manuf. Process."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"277","DOI":"10.1016\/j.msea.2014.03.135","article-title":"Effect of Zinc Interlayer on Ultrasonic Spot Welded Aluminum-to-Copper Joints","volume":"607","author":"Balasundaram","year":"2014","journal-title":"Mater. Sci. Eng. A"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"233","DOI":"10.1016\/j.matchar.2018.03.010","article-title":"Interfacial Microstructure Evolution and Weld Formation during Ultrasonic Welding of Al Alloy to Cu","volume":"139","author":"Fujii","year":"2018","journal-title":"Mater. Charact."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"141724","DOI":"10.1016\/j.msea.2021.141724","article-title":"Dynamic Weld Evolution during Ultrasonic Welding of Cu\u2013Al Joints","volume":"823","author":"Ma","year":"2021","journal-title":"Mater. Sci. Eng. A"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"6320","DOI":"10.1016\/j.msea.2010.06.038","article-title":"Mechanisms of Joint and Microstructure Formation in High Power Ultrasonic Spot Welding 6111 Aluminium Automotive Sheet","volume":"527","author":"Bakavos","year":"2010","journal-title":"Mater. Sci. Eng. A"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"393","DOI":"10.1016\/j.matdes.2015.08.042","article-title":"Mechanical Analysis of Ultrasonic Welding Considering Knurl Pattern of Sonotrode Tip","volume":"87","author":"Chen","year":"2015","journal-title":"Mater. Des."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1016\/j.scriptamat.2016.12.030","article-title":"High-Strain-Rate Deformation in Ultrasonic Additive Manufacturing","volume":"135","author":"Fujii","year":"2017","journal-title":"Scr. Mater."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"3077","DOI":"10.1016\/0001-6160(88)90045-4","article-title":"Effect of Rate Sensitivity on the Stability of Torsion Textures","volume":"36","author":"Toth","year":"1988","journal-title":"Acta Metall."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1016\/j.matchar.2017.06.018","article-title":"Dynamic Recovery and Recrystallization Mechanisms during Ultrasonic Spot Welding of Al-Cu-Mg Alloy","volume":"132","author":"Xie","year":"2017","journal-title":"Mater. Charact."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"340","DOI":"10.1016\/j.matchar.2016.06.004","article-title":"Grain Structure, Texture and Mechanical Property Evolution of Automotive Aluminium Sheet during High Power Ultrasonic Welding","volume":"118","author":"Haddadi","year":"2016","journal-title":"Mater. Charact."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1016\/j.scriptamat.2016.02.004","article-title":"Microstructure and Lap Shear Strength of the Weld Interface in Ultrasonic Welding of Al Alloy to Stainless Steel","volume":"116","author":"Fujii","year":"2016","journal-title":"Scr. Mater."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"234","DOI":"10.1016\/j.actamat.2014.04.043","article-title":"Mechanism of Weld Formation during Very-High-Power Ultrasonic Additive Manufacturing of Al Alloy 6061","volume":"74","author":"Shimizu","year":"2014","journal-title":"Acta Mater."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"175","DOI":"10.1016\/j.jmatprotec.2013.09.005","article-title":"Evolution of the Bulk Microstructure in 1100 Aluminum Builds Fabricated by Ultrasonic Metal Welding","volume":"214","author":"Ji","year":"2014","journal-title":"J. Mater. Process. Technol."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"522","DOI":"10.1179\/1362171815Y.0000000022","article-title":"Numerical Analysis of Temperature Distribution during Ultrasonic Welding Process for Dissimilar Automotive Alloys","volume":"20","author":"Chen","year":"2015","journal-title":"Sci. Technol. Weld. Join."},{"key":"ref_54","unstructured":"Massalski, T.B., and Okamoto, H. (1990). Binary Alloy Phase Diagrams, ASM International."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"939","DOI":"10.1016\/j.scriptamat.2004.12.015","article-title":"Enhanced Diffusion and Phase Transformations during Ultrasonic Welding of Zinc and Aluminum","volume":"52","author":"Gunduz","year":"2005","journal-title":"Scr. Mater."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"879","DOI":"10.1007\/s00170-019-03582-9","article-title":"Atomistic Simulation of Diffusion Bonding of Dissimilar Materials Undergoing Ultrasonic Welding","volume":"103","author":"Samanta","year":"2019","journal-title":"Int. J. Adv. Manuf. Technol."}],"container-title":["Materials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1944\/16\/8\/3033\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T19:14:21Z","timestamp":1760123661000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1944\/16\/8\/3033"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,4,12]]},"references-count":56,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2023,4]]}},"alternative-id":["ma16083033"],"URL":"https:\/\/doi.org\/10.3390\/ma16083033","relation":{},"ISSN":["1996-1944"],"issn-type":[{"value":"1996-1944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,4,12]]}}}