Experimental Investigation of the Effect of Using Tools with Tapered Pins in Friction Stir Welding (FSW) of AA6061-T6 Aluminum Alloy

Subject Areas :

Saleh Al Khatour ¹ (Department of Mechanical Engineering, Kermanshah Branch, Islamic Azad University, Kermanshah, Iran)
Maziar Mahdipour Jalilian ² (Department of Mechanical Engineering, Kermanshah Branch, Islamic Azad University, Kermanshah, Iran)
Mahdi Karami Khorramabadi ³ (Department of Mechanical Engineering, Khorramabad Branch, Islamic Azad University, Khorramabad, Iran)

Received: 2024-02-13 Accepted : 2024-05-01 Published : 2024-06-17

Keywords: Friction Stir Welding (FSW), Tool Geometry, Tapered Pin, Aluminum Alloy, Strength of Weld,

Abstract :

The present study investigated the effect of using tools with tapered pins in Friction Stir Welding (FSW) of AA6061-T6 aluminum alloy. Two techniques named conventional FSW and Refill Friction Stir Welding (RFSW) were used for this purpose. Five tools with different tapered angles (0, 5, 10, 15, and 20 degrees) were used. To study the mechanical properties, tensile, three-point bending, and Vickers microhardness tests were performed. Macrographic and microstructural tests were also used to investigate the metallurgical properties of the welded samples. Based on the results, it was found that the key factors determining the ductility and strength of the welded specimens are the type of welding process (conventional FSW or RFSW) and the geometry of the tool pin (straight or tapered pin). Furthermore, it was found that all specimens welded by RFSW have higher tensile strength and elongation than the samples welded by conventional FSW.

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