REVIEW published: 30 April 2021 doi: 10.3389/fmats.2021.647112 Edited by: Mazeyar Parvinzadeh Gashti, PRE Labs Inc., Canada Reviewed by: Mohammadreza Shokouhimehr, Seoul National University, South Korea Hamid Reza Baharvandi, University of Tehran, Iran Guntram Wagner, Technische Universität Chemnitz, Germany *Correspondence: Yuh-Chung Hu ychu@niu.edu.tw Specialty section: This article was submitted to Polymeric and Composite Materials, a section of the journal Frontiers in Materials Received: 29 December 2020 Accepted: 06 April 2021 Published: 30 April 2021 Citation: Selvaraj SK, Srinivasan K, Chadha U, Mishra R, Arpit K, Apurb K and Hu Y-C (2021) Contemporary Progresses in Ultrasonic Welding of Aluminum Metal Matrix Composites. Front. Mater. 8:647112. doi: 10.3389/fmats.2021.647112 Contemporary Progresses in Ultrasonic Welding of Aluminum Metal Matrix Composites Senthil Kumaran Selvaraj 1 , Kathiravan Srinivasan 2 , Utkarsh Chadha 1 , Rajat Mishra 1 , Kurane Arpit 1 , Kumar Apurb 1 and Yuh-Chung Hu 3 * 1 Department of Manufacturing Engineering, School of Mechanical Engineering, Vellore Institute of Technology (VIT), Vellore, India, 2 School of Information Technology and Engineering, Vellore Institute of Technology (VIT), Vellore, India, 3 Department of Mechanical and Electromechanical Engineering, National ILan University, Yilan City, Taiwan The Aluminum metal matrix with particulate reinforcements is the new future of the coming industrial revolution due to the higher strength and availability. Composite reinforcements such as SiC, TiB2, B4C, and others contribute significantly to the increased strength of the Aluminum metal matrix, which can be an optimal choice, also at a lower cost, in some applications where Aluminum is considered or proven to withstand high temperatures. Ultrasonic welding is the process, where, we get the electrical energy, which converts and amplifies into vibration energy for the welding to occur. The challenge we face today is the thickness limitations in ultrasonic welding. The ultrasonic welding of the Aluminum metal sheet with the reinforcements may affect it, as the addition of particulate reinforcements will increase the strength of the Aluminum matrix. Ultrasonic welding can only support a metal sheet with a thickness of up to 2.5 mm in the case of an Aluminum plain sheet. However, if the strength of the Aluminum metal matrix increases, the next step is to achieve ultrasonic welding with the same thickness of Aluminum matrix and reinforced composites that have greater strength than a standard Aluminum sheet. This review will focus on the parameters and the factors which may help decrease the difficulties of Ultrasonic Welding of Aluminum MMC, alongside reviewing the current technologies and research works. Keywords: aluminum metal matrix composites, particulate reinforcement, ultrasonic welding, ultrasonic vibrations, welding engineering INTRODUCTION Aluminum, the most abundant metal on earth’s crust, is well known for its corrosion resistance and low density, which allows it to be a benefit for the aviation industry (Wu et al., 1996; Reddy et al., 2009; Ramnath et al., 2014; Raviteja et al., 2014; Shinde et al., 2020). The oxygen bonds with pure Aluminum are quite strong, which is forms or as alumina from the bauxite ore. It undergoes the oxidation process when exposed to the external atmosphere and forms a coating of Alumina (Al2O3). It is hard to surpass this protection over pure Aluminum when kept in an open atmosphere. It has a higher melting temperature than that of pure Aluminum if taken under ideal conditions. The corrosion-resistant nature caused by alumina’s presence over the surface of pure Aluminum is a boon to the industries. The particulate reinforcement in Aluminum enhances its mechanical properties. Also, this brings an advantage for the welding of an Aluminum sheet, which was usually tricky due to alumina’s presence, which acted as a protective shield over the Aluminum surface. Aluminum is the metal available in Frontiers in Materials | www.frontiersin.org 1 April 2021 | Volume 8 | Article 647112