International Journal of Engineering Research and Advanced Technology (IJERAT) E-ISSN : 2454-6135 DOI: http://doi.org/10.31695/IJERAT.2018.3347 Volume.4, Issue 12 December -2018 www.ijerat.com Page 1 DOI : 10.31695/IJERAT.2018.3347 Investigation of the Effect of Different Working Mediums on Turning Al7075-T6 Alloy Suleyman Cinar Cagan 1 and Dr. Berat Baris Buldum 1 Research Scholar 1 Department of Mechanical Engineering 1 Mersin University, Engineering Faculty Mersin Turkey _______________________________________________________________________________________ ABSTRACT The surface quality of the manufactured parts is an important factor affecting the functional properties such as corrosion resistance, the fatigue strength of the part. For this reason, this study aims to develop surface roughness of Al 7075-T6 alloy material which is generally used in the aviation and manufacturing industry. In this study, the machinability of Al 7075-T6 alloy with different high speed turning parameters was investigated. Two different mediums (Dry and boron oil), three different cutting speeds (400, 800 and 1600 m/min) and three different feed rates (0.1, 0.2 and 0.4 mm/rev) were determined as parameters in the experiments. The optimum parameters for the determination of surface roughness values of Al 7075-T6 alloy were determined. The most important parameters affecting the surface roughness of the Al 7075-T6 alloy have been found out to be the feed rate. It appears that the medium and cutting speed examined have not had a significant effect on the surface roughness. When the test results are taken into consideration, the best surface roughness value is reached with parameters: medium: boron oil, cutting speed 400 m/min and feed rate: 0.1 mm/rev. Key Words: Al 7075-T6 alloy, Turning, Taguchi method, Surface roughness. _______________________________________________________________________________________________ 1. INTRODUCTION Aluminum and its alloys have become increasingly industrialized due to their lightweight as well as their strength and easy forming ability [1-3]. Aluminum alloys play a significant role in the development of space, aviation, automotive, weapons and defence industry due to their mechanical properties as well as their lightweight (density is 2.81 g/cm3). Within these alloys, the importance and application areas of 7075-T6 grade aluminum alloys are increasing especially in the defence and aerospace industry [4, 5]. Machinability, the material is expressed as a convenience or difficulty in machining in a chip removal process involving cutting conditions such as cutting speed, feed rate, cutting force, number of passes, and chip depth [6, 7]. Machinability of a material can be defined by measuring components such as tool wear, chip formation, tool life, surface roughness and cutting force [6, 8]. Surface roughness is one of the most important characteristics affecting the product quality and is of great importance in the functional behaviour of the machined parts [9-11]. The manufacturing process is the process of converting the raw materials planned to be used for various purposes into finished products [12]. Products with poor surface quality cannot meet the functional requirements and cause extremely high production costs [13]. Therefore, the improvement of the surface quality of the products and the economics of the production processes become a very important issue for the production of finished products [14, 15]. Although there are studies about the machinability of aluminum alloys, it is observed that there is the limited number of studies on the effect of the turning process of Al 7075-T6 on the surface quality. In this study, the effect of surface roughness on the different parameters (mediums, cutting speed and feed rate) of the Al 7075-T6 alloy turning process was investigated. Also, the experimental design was planned by selecting L 18 Taguchi method. In this study,