Available online at www.sciencedirect.com ScienceDirect Materials Today: Proceedings 4 (2017) 452–458 www.materialstoday.com/proceedings * Corresponding author. Tel.: 8745819112; 9034324520. E-mail address: rathee8@gmail.com 2214-7853©2017 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of Conference Committee Members of 5th International Conference of Materials Processing and Characterization (ICMPC 2016). 5th International Conference of Materials Processing and Characterization (ICMPC 2016) Analysis of Microstructural Changes in Enhancement of Surface Properties in Sheet Forming of Al alloys via Friction Stir Processing Sandeep Rathee a* , Sachin Maheshwari a , Arshad Noor Siddiquee b , Manu Srivastava a aDivision of Manufacturing Processes and Automation Engineering,Netaji Subhas Institute of Technology, New Delhi, India bDepartment of Mechanical Engineering,Jamia Millia Islamia University, New Delhi, India Abstract Weight reduction is one of the major objectives in engineering design and manufacturing, especially in automotive and aircraft industries. Aluminium (Al) alloys provide the solution for weight reduction in various structural applications. Forfurther enhancement ofsurface properties of these alloys, their surface composites are fabricated which exhibit high strength - weight ratio, better corrosion resistance, improved mechanical & wear properties as compared to base alloys. In this work, an attempt has been made to enhance the processed-layerhardness of AA 6063 sheets by synthesizing AA 6063/SiC surface composites using friction stir processing (FSP). Single pass FSP was performed on AA 6063 sheets using tool rotational speedat three levels of 900, 1120and 1400 rpm respectively.Traverse speed was maintained at a constant level of 40 millimetres/minute and tool tilt angle was kept at 2˚. Optical microscopy was employed for observing microstructureof fabricated composites. Uniform distribution of SiC particles in the metal matrix was achieved.The Combination of 1120 rpm, 40 mm/min and 2 ˚ gave most homogeneous distribution and highest microhardness of 87 Hv. No interfacial reaction was observed between the aluminium matrix and SiC particles. ©2017 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of Conference Committee Members of 5th International Conference of Materials Processing and Characterization (ICMPC 2016). Keywords:Aluminiumalloy;friction stir processing; SiC; microstructure;microhardness;rotational speed. 1. Introduction The demand for weight reduction in various engineering applications like aerospace, automobiles, marines and other structural applications necessitates the use of lightweight materials like aluminium, magnesium, titanium etc. in place of ferrous alloys. Furthermore, apart from the weight reduction several other functional characteristics such as corrosion and wear resistance etc.are of added advantage.Aluminium alloy sheets are quite promising