Effect of rolling on friction stir welded joints of aluminum alloy

被引:0
|
作者
Jin Y. [1 ,2 ]
Wu Y. [1 ]
Wang X. [1 ,2 ]
Guo T. [1 ,2 ]
机构
[1] State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Lanzhou University of Technology, Lanzhou
[2] Material Science and Engineering Institute, Lanzhou University of Technology, Lanzhou
关键词
7050 aluminum alloy; Friction stir welding; Mechanical properties; Microstructure; Rolling;
D O I
10.12073/j.hjxb.2019400099
中图分类号
学科分类号
摘要
The upper and back surface of a friction stir welded joint of 5 mm thick 7050 aluminum alloy were rolled by a self-made rolling head. It was compared with the welded joints without rolling. The effect of rolling on the performance of welded joints was studied. The results showed that the roughness of joint surface was reduced from 9.58 μm (maximum value) to 0.85 μm (mean value). The surface layer happened severe plastic deformation, and the grains were remarkably refined to form a fine grain layer of about 200 μm thick. The grain refinement of the subsurface layer was reduced, and a shear band was generated in the weld nugget zone. The hardness of the joint surface was obviously improved, and the average hardness was as high as HV210, which was 91% higher than the hardness HV110 before rolling. The residual stress of the joint surface changed from the original tensile stress to the compressive stress, and the maximum residual compressive stress field depth was about 200 μm. The source was moved from the surface layer to the subsurface layer, and the fatigue life was significantly improved. © 2019, Editorial Board of Transactions of the China Welding Institution, Magazine Agency Welding. All right reserved.
引用
收藏
页码:50 / 54
页数:4
相关论文
共 12 条
  • [1] Wu L.H., Wang D., Xiao B.L., Et al., Microstructural evolution of the thermomechanically affected zone in a Ti-6Al-4V friction stir welded joint, Scripta Materialia, 78, 5, pp. 17-20, (2014)
  • [2] Wang T., Wang D.P., Liu G., Et al., Investigations on the nanocrystallization of 40Cr using ultrasonic surface rolling processing, Applied Surface Science, 225, 5, pp. 1824-1829, (2008)
  • [3] Xie R., Qiu X., Chen F., Et al., Surface nanocrystallization of 7A52 aluminum alloy welded joint using ultrasonic impact treatment, Transactions of the China Welding Institution, 35, 12, pp. 35-38, (2014)
  • [4] Hao Z., Li X., Li Y., Et al., Effect of multiple rotary rolling on the surface of friction stir weld of aluminum alloy, Transactions of the China Welding Institution, 38, 2, pp. 125-128, (2017)
  • [5] Hatamleh O., A comprehensive investigation on the effects of laser and shot peening on fatigue crack growth in friction stir welded AA2195 joints, International Journal of Fatigue, 31, 5, pp. 974-988, (2009)
  • [6] Li W.Y., Li N., Yang X.W., Et al., Impact of cold spraying on microstructure and mechanical properties of optimized friction stir welded AA2024-T3 joint, Materials Science & Engineering A, 702, pp. 73-80, (2017)
  • [7] Wagner L., Mhaede M., Wollmann M., Et al., Surface layer properties and fatigue behavior in Al 7075-T73 and Ti-6Al-4V: comparing results after laser peening: shot peening and burnishing, International Journal of Structural Integrity, 2, 2, pp. 185-199, (2011)
  • [8] Chui P.F., Suna K.N., Suna C., Effect of surface induced by fast multiple rotation rolling on hardness and corrosion behavior of 316L stainless steel, Applied Surface Science, 257, 15, pp. 6787-6791, (2011)
  • [9] Jin Y., Huo R., Wang X., Et al., Effect of rotation speed on fracture characteristics of 7055 aluminum alloy friction stir welding joint, Transactions of the China Welding Institution, 38, 2, pp. 10-13, (2017)
  • [10] Fu R., Sun Z., Sun R., Et al., Improvement of weld temperature distribution and mechanical properties of 7050 aluminum alloy butt joints by submerged friction stir welding, Material and Design, 32, 10, pp. 4825-4831, (2011)