High Rotation Speed Friction Stir Welding for 2014 Aluminum Alloy Thin Sheets
- PDF / 3,259,686 Bytes
- 9 Pages / 593.972 x 792 pts Page_size
- 46 Downloads / 198 Views
JMEPEG DOI: 10.1007/s11665-017-2524-y
High Rotation Speed Friction Stir Welding for 2014 Aluminum Alloy Thin Sheets Shujin Chen, Yang Zhou, Junrong Xue, Ruiyang Ni, Yue Guo, and Jianghui Dong (Submitted June 2, 2016; in revised form December 11, 2016) In this study, 2014 aluminum alloy sheets with 1 mm thickness are welded successfully by friction stir welding (FSW) robot under the condition of high rotation speed. When the high rotation speed of 10,00016,500 rpm is applied, the lower axial pressure (less than 200 N) is obtained, which reduces stiffness requirements for equipment. Welding deformation is inevitable because high rotation speed can easily result in rapid heating rate and uneven heat input. The welding distortion caused by two cooling methods is measured, respectively, by laser range finder. The experimental results show that the welding distortion is smaller under the condition of water cooling. When the rotation speed is up to 15,000 rpm and welding speed 50-170 mm/min, the whole welding process is controllable. Under the higher rotation speed condition, the welding defects disappear gradually and more stable mechanical properties can be obtained up to 75% of base metal (x = 16,000 rpm, m = 110 mm/min). The results of different welding parameters demonstrate that the high rotation speed can increase material mixing and reduce the axial force (z force), and it can benefit lightweight sheet welding by using FSW robot. Keywords
aluminum alloy, friction stir welding, high rotation speed, mechanical behavior, thin sheet
1. Introduction As FSW evolved through two decades after its discovery, it has become a viable manufacturing technology for the structural assembly of metallic sheet and materials for applications in various industries, including aerospace, automobile and shipbuilding. As Rajakumar et al. (Ref 1) and Cam et al. (Ref 2, 3) suggested, FSW can achieve solid-state welding without filler materials, which effectively avoids cracks and porosity defects. Actually, the FSW machine is developed to be more efficient and automated. At the same time, the current state of the art of FSW is developing beyond Al alloys, including Mg alloys, Cu alloys, steels, Ti alloys and metal matrix composites, focusing particularly on microstructural aspects, joints properties, material flow and material selection for tooling. The basic principle of FSW is associated with plunging a rotating tool into the workpiece. The rotating tool pin slowly penetrates the workpiece until the tool shoulder touches the top surface of the workpiece; then, it is held there while the metal around is being softened by generated frictional heat. Subsequently, the tool traverses along the weld seam and the weld is formed under the heat and plastic deformation. Since FSW uses a rotating tool, similarly to how a milling machine uses an end mill, computer Shujin Chen, Yang Zhou, Junrong Xue, and Ruiyang Ni, School of Material Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, China; Yue Guo, Hua Heng Weldin
Data Loading...
