Investigations of the Mechanical and Microstructural Effects of Pinless Tool Geometry on Friction Stir Spot Welding Proc
- PDF / 2,186,539 Bytes
- 9 Pages / 595.276 x 790.866 pts Page_size
- 111 Downloads / 201 Views
ORIGINAL ARTICLE
Investigations of the Mechanical and Microstructural Effects of Pinless Tool Geometry on Friction Stir Spot Welding Process ¨ zgu¨l1 • Orhan Dedeog˘lu2 Hande Gu¨ler O
Received: 4 February 2020 / Accepted: 28 June 2020 The Indian Institute of Metals - IIM 2020
Abstract In this study, mechanical properties, macrostructure and microstructure of the friction stir spot weld joints were investigated under the influence of pinless tool geometry and different rotation speed parameters (1350, 1850 and 2530 rpm) using Al5754 plates. Tensile shear strength tests were carried out for joints of different process parameters, and fracture surfaces were inspected by scanning electron microscopy; in addition, fracture modes of the joints were also evaluated. According to the results, the maximum strength values were obtained at 1850 rpm rotation speed, and ductile and brittle fractures were observed together. Keywords Friction stir spot welding Aluminum alloys Hardness Shear force
1 Introduction Today, advances in automotive technology lead to the development of different production methods. One of these manufacturing methods, friction stir spot welding, was developed by Mazda and Kawasaki Heavy Industries, and it was first used in mass production of the rear door panel in 2003 [1, 2]. This method offers as an option to resistance
¨ zgu¨l & Hande Gu¨ler O [email protected] 1
Department of Automotive Engineering, Faculty of Engineering, Uludag University, 16059 Gorukle-Bursa, Turkey
2
Department of Automotive Engineering, Graduate School of Natural and Applied Sciences, Uludag University, 16059 Gorukle-Bursa, Turkey
spot welding, and the tool which rotates at a certain speed rubs the upper surface of the pair of materials to be joined, and the materials soften due to friction; the moving tool stays in the material pair for a certain period of time and combines the material pair with the resulting heat and pressure effect, and the welding process is completed by retracting the tool [3]. The literature review of this welding method is generally about determining process parameters and obtaining optimum welding properties. As a result of the experimental and finite element analysis conducted by Li et al. [4], it was found that the optimum welding tool geometry is the halfthreaded pin because of the higher cross-tension failure loads. In another study [5], 0.8-mm low-carbon steel was friction-stir-spot-welded with different rotational speed, plunge depth and dwell time parameters; it was concluded that dwell time is the most important parameter affecting the mechanical properties. In the study of the welding of different aluminum materials [6], the effects of rotational speed and tool holding time were examined, and it was found that strength increases with decreasing rotational speed and increasing tool holding time. Piccini and Svoboda [7] investigated the optimum welding parameters of Al 5052 and low-carbon steel and the optimum fracture load parameters reported as the welding tool geometry is
Data Loading...
