A parametric study of friction stir welded AA6061/SiC AMC and its effect on microstructure and mechanical properties Devender Kumar, Denny J. Ottarackal, Uttam Acharya ⇑ , Tanmoy Medhi, Barnik Saha Roy, Subhash Chandra Saha Department of Mechanical Engineering, NIT Agartala, India article info Article history: Received 11 November 2019 Received in revised form 24 February 2020 Accepted 27 February 2020 Available online xxxx Keywords: Aluminum matrix composites Friction stir welding Microstructure Mechanical properties Parametric study abstract The present study investigates the effect of parametric variations on microstructural and mechanical properties of friction stir welded (FSW) 6 mm thick as-cast AA6061/SiC Aluminum Matrix Composite (AMC) joints. The study has been designed by varying the traverse speed, tool rotational speed and tilt angle up to various levels. Microstructural investigations of welded samples were performed using low-resolution Light Optical Microscopy (LOM) and Scanning Electron Microscopy (SEM). Energy- dispersive X-ray spectroscopy (EDS) is conducted to analyze the chemical composition and reinforcement distribution. To see the effect of parametric variation on mechanical property of the joint, ultimate tensile strength (UTS), percentage (%) elongation and hardness are investigated to support the study. As the opti- mum parametric values were somewhere missing in context to FSW of AMCs therefore present study deals with carefully deriving optimum weld parameters contributing to both sound weld as well as mechanical properties of the welded specimen. Tool tilt angle played a major role in determining the UTS of the welded specimen besides the tool rotational speed and welding speed making it one of the critical parameter for deciding mechanical properties of the welded specimen. Ó 2020 Elsevier Ltd. All rights reserved. Selection and Peer-review under responsibility of the scientific committee of the International Mechan- ical Engineering Congress 2019: Materials Science. 1. Introduction The metal possesses higher strength, high-temperature resis- tance and ductility, but somewhere metals lack higher stiffness. But if we speak about ceramic materials, they are stiffer and stron- ger in nature, though ceramic materials lack ductility and are brit- tle in nature. To gain the enhanced and desired intermediate properties of these materials, both the materials have to be mixed in the right quantity and proportion resulting in the formation of new material that will have superior properties than both parent materials. The metal which is added to prepare AMC is called the matrix and it is added in a greater proportion and the ceramic which is added in smaller quantity is known as reinforcement. The reinforcements can be used in various manners such as fibers, whiskers and particulates [1]. Particulate reinforced composites have more applications than the other two. Generally, reinforce- ments configurations like fiber and flake exhibit anisotropic properties. But isotropic behavior is observed in the case of the particulate form of reinforcement present in the composites. One more advantage of particulate composites is that they are easier to produce when compared with fiber or flake type of reinforce- ment. Other advantages of particulate composites include improved strength, ability to withstand at higher operating tem- perature, resistance to oxidation, etc. [2]. Al6061 can be the best- suited option for matrix owing to its enhanced formability charac- teristics and strength modification alternates of composites by proper heat treatment selection [1]. Al-SiC MMCs (AMCs) are widely used for making brake pads, fuel tanks in aerospace mis- sions, etc. AMC helps to enhance the strength and wear resistance of brake drum parts [3]. SiC is a good choice to be added as rein- forcement material in the Al matrix as it will further enhance the desired mechanical properties namely UTS, yield strength, wear resistance, the hardness of Al. Al 2 O 3 reinforcements can also be another alternative but its poor wetting behavior with aluminum and higher weight percentage which increases the porosity in AMC limits its usage. In Al-SiC AMCs, the presence of SiC particu- lates delivers higher yield strength as well as an increased elastic https://doi.org/10.1016/j.matpr.2020.02.933 2214-7853/Ó 2020 Elsevier Ltd. All rights reserved. Selection and Peer-review under responsibility of the scientific committee of the International Mechanical Engineering Congress 2019: Materials Science. ⇑ Corresponding author. E-mail address: uttamacharya1989@gmail.com (U. Acharya). Materials Today: Proceedings xxx (xxxx) xxx Contents lists available at ScienceDirect Materials Today: Proceedings journal homepage: www.elsevier.com/locate/matpr Please cite this article as: D. Kumar, D. J. Ottarackal, U. Acharya et al., A parametric study of friction stir welded AA6061/SiC AMC and its effect on microstructure and mechanical properties, Materials Today: Proceedings, https://doi.org/10.1016/j.matpr.2020.02.933