International Journal of Mechanical & Mechatronics Engineering IJMME-IJENS Vol:20 No:01 144 202601-4343-IJMME-IJENS © February 2020 IJENS I J E N S A Multi-Response Optimization of FSW process parameters on AA5052-H111 using Taguchi Method Rania Mostafa 1* , Reham Al-Mahdy 2 , Ahmed El-Keran 3 Production Engineering & Mechanical Design Dept., Faculty of Engineering, Mansoura University, Mansoura, Egypt. 1 Lecturer, ranmos75@mans.edu.eg ranmos75@yahoo.com, * The corresponding author 2 rehamalmahdy18@gmail.com 3 Assoc. Professor, el_keran@mans.edu.eg Abstract-- In this study, Friction Stir Welding process is applied to weld two plates of AA5052-H111 as a butt joint using Stepped and Tapered pin profile tools. Design of Experiment is planned by Minitab17 for the welding conditions; Welding Speed (W.S), the Rotational Speed (R.S), Tool Tilting Angle (T.A) and the tool design. Visual and mechanical (Tensile UTS and microhardness VHN) tests are carried out then the multi-response optimization based on Taguchi-method is performed to identify the highest effect of these parameters. At welding conditions; R.S 1600 rpm, W.S 17mm/min and T.A 2° using the stepped tool, the UTS and VHN are optimum and extend to 90.5% and 150% of the base material, respectively. By observing the resulted samples; the usage of Stepped tool contributes to the smooth surface and helps in the good appearance of the weld quality. Also, the welded samples using the Tapered tool obtains higher hardness. Index Term-- Friction stir welding, Taguchi method, multi- response optimization, Design of Experiment 1. INTRODUCTION Friction stir welding (FSW) is an innovative welding process commonly known as a solid-state welding process invented by Wayne Thomas at TWI [1]. The core benefit of FSW joint is to weld material without reaching the fusion temperature. It enables welding almost all types of aluminum alloys, even the ones classified as non-weld able by fusion welding due to the hot cracking and poor solidification microstructure in the fusion zone. FSW is particularly appropriate for the welding of high strength alloys such as Aluminum 5052 and dissimilar material [2]. The benefits of FSW such as metallurgical, environments and energy benefits are summarized in Ref. [3]. Aluminum 5052 has a wide variety of applications in transportation, shipbuilding, marine and aircraft industries [4]. The welding tool of FSW usually consists of a pin and a shoulder. Most heat generation occurs as a result of the friction between the tool and the material, particularly the tool shoulder and the butt joint area of the work pieces. The tool pin mainly breaks and shatters abutting work pieces and stirs the refined grains. A strong compaction or bonding of welded regions filled with soft and shattered grains is induced by both the tool shoulder and the under formed work pieces, which surround the welded region [5, 6]. FSW parameters such as down force, welding speed, tool rotation speed, tilting angle and insertion depth of the tool pin must be controlled. The effect of every parameter is shown in Table 1. The quality of friction stir welds depends on the use of an optimum combination of these process parameters as shown in Fig.1. Table I The effects of FSW parameters [2] Parameter Effects Rotational speed Frictional heat, “stirring”, oxide layer breaking and mixing of material. Tilt angle The appearance of the weld, thinning. Welding speed Appearance, heat control. Down force Frictional heat, maintaining contact conditions.