Effect of the shoulder size and dwell time on the static Strength and fracture mode of projection friction stir spot welded 2024 aluminum alloy

Subject Areas : journal of New Materials

F. zarghani ¹ (- M.Sc.Student, Department of Materials and Polymer Engineering, Hakim Sabzevari University, Sabzevar, Iran)
seid m. mousavizade ² (Assistant Professor, Department of Materials and Polymer Engineering, Hakim Sabzevari University, Sabzevar, Iran)
G.R Ebrahimi ³ (- Association Professor, Department of Materials and Polymer Engineering, Hakim Sabzevari University, Sabzevar, Iran)
H.R. Ezatpour ⁴ (Faculty of Engineering, Sabzevar University of New Technology, Sabzevar, Iran)

Received: 2017-06-01 Accepted : 2017-08-27 Published : 2018-07-23

Keywords: mechanical properties, Friction stir spot welding, 2024Aluminium alloy, Fracture mode,

Abstract :

      Automotive industry has developed a variant of the Friction Stir Welding named Friction Stir Spot Welding (FSSW), to replace resistance spot welding (RSW) for aluminum sheets. It is claimed that the use of energy and the investment cost are decreased with using of friction stir spot welding in comparison with resistance spot welding. However, one of the disadvantages of FSSW technique is that a keyhole generally remains at the center of the stir zone. Keyhole defect can reduce the mechanical properties of FSSW joints. A novel friction stir spot welding technique was developed with the purpose to improve the mechanical property of the joints by removing the keyhole. This novel FSSW method was applied to 2024 Al alloy sheets, 1 mm in thickness, under different shoulder size and dwell times. The effect of shoulder size and dwell time on the mechanical properties of the spot joints has been studied. Studies show that this new spot welding technique can produce a defect-free metallurgical bond with a homogenous fine grain microstructure. The welding parameters variations change the bonding area, depth stir zone, upper sheet thickness, grain size and mechanical properties of the welds.

References:

References:

1- Q. Chu, X. Yang, W. Li, and Y. Li, “Microstructure and mechanical behaviour of pinless friction stir spot welded AA2198 joints,” vol. 21, no. 3, pp. 164–170, 2016. 

2- M. Fujimoto, S. Koga, N. Abe, Y. S. Sato, and H. Kokawa, “Microstructural analysis of stir zone of Al alloy produced by friction stir spot welding,” vol. 13, no. 7, pp. 663–670, 2008. 

3- Z. Zhang, X. Yang, J. Zhang, G. Zhou, X. Xu, and B. Zou, “Effect of welding parameters on microstructure and mechanical properties of friction stir spot welded 5052 aluminum alloy,” Mater. Des., vol. 32, no. 8–9, pp. 4461–4470, 2011.

4- M. Paidar, A. Khodabandeh, H. Najafi, and A. S. Rouh-aghdam, “Effects of the tool rotational speed and shoulder penetration depth on mechanical properties and failure modes of friction stir spot welds of aluminum 2024-T3 sheets,” J. Mech. Sci. Technol., vol. 28, no. 12, pp. 4893–4898, 2014.     

5- A. Gerlich, P. Su, and T. H. North, “Tool penetration during friction stir spot welding of Al and Mg alloys,” J. Mater. Sci., vol. 40, no. 24, pp. 6473–6481, 2005.

6- D. Zhang and T. Shibayanagi, “Material flow during friction stir spot welding of dissimilar Al2024 / Al materials,” vol. 31, no. 9, pp. 1077–1087, 2015.       

7 - بررسی استعداد به خوردگی مرز دانه ای مقطع جوشکاری شده آلیاژ آلومینیوم6061 به روش جوشکاری اصطکاکی اغتشاشی. فرهاد غروی، کامران امینی و فیروز فدائی.مجله مواد نوین جلد 5 شماره 3 سال 1394.

8- G. Buffa, P. Fanelli, L. Fratini, and F. Vivio, “Influence of joint geometry on micro and macro mechanical properties of friction stir spot welded joints,” Procedia Eng., vol. 81, no. October, pp. 2086–2091, 2014.

9- N. Pathak, K. Bandyopadhyay, M. Sarangi, and S. K. Panda, “Microstructure and mechanical performance of friction stir spot-welded aluminum-5754 sheets,” J. Mater. Eng. Perform., vol. 22, no. 1, pp. 131–144, 2013.           

10- M. Paidar, A. Khodabandeh, H. Najafi, and A. S. Rouh-aghdam, “An investigation on mechanical and metallurgical properties of 2024-T3 aluminum alloy spot friction welds,” Int. J. Adv. Manuf. Technol., vol. 80, no. 1–4, pp. 183–197, 2015.  

11- R.Kartihikeyan, V.Balasubramaian. O.ptimaization of Electrica Resistance Spot Welding and Comparasion with Friction Stir Spot Welding of AA2024 Aluminum Alloy joints.5th International Conference of Material Processing 2017.
 

12- W. Li, J. Li, Z. Zhang, D. Gao, W. Wang, and C. Dong, “Improving mechanical properties of pinless friction stir spot welded joints by eliminating hook defect,” J. Mater., vol. 62, pp. 247–254, 2014.

13- Z.M.Su, R.Y.He,P.C.Lin. Fatigue of alclad AA2024 swept friction stir spot welds in cross tension speciments. Jornal pf Material Processing Technology 2016.

14- X. Song, L. Ke, L. Xing, F. Liu, and C. Huang, “Effect of plunge speeds on hook geometries and mechanical properties in friction stir spot welding of A6061-T6 sheets,” Int. J. Adv. Manuf. Technol., vol. 71, no. 9–12, pp. 2003–2010, 2014.      

15- Z. . Shen, Y. . Chen, J. S. C. . Hou, X. . Yang, and A. P. . Gerlich, “Influence of processing parameters on microstructure and mechanical performance of refill friction stir spot welded 7075-T6 aluminium alloy,” Sci. Technol. Weld. Join., vol. 20, no. 1, pp. 48–57, 2015.          

16- A. Gerlich, M. Yamamoto, and T. H. North, “Local melting and cracking in Al 7075-T6 and Al 2024-T3 friction stir spot welds,” vol. 12, no. 6, pp. 472–480, 2007.

17- D. Bakavos and P. B. Prangnell, “Effect of reduced or zero pin length and anvil insulation on friction stir spot welding thin gauge 6111 automotive sheet,” vol. 14, no. 5, pp. 443–456, 2009.

18- M. De Leon and H. Shin, “Material flow behaviours during friction stir spot welding of lightweight alloys using pin and pinless tools,” vol. 00, no. 0, pp. 1–7, 2015.

19- Y. F. Sun, H. Fujii, N. Takaki, and Y. Okitsu, “Novel spot friction stir welding of 6061 and 5052 Al alloys,” vol. 16, no. 7, pp. 605–612, 2011.     

20- S. Venukumar, B. Baby, S. Muthukumaran, and S. V. Kailas, “Microstructural and Mechanical Properties of Walking Friction Stir Spot Welded AA 6061-T6 Sheets,” Procedia Mater. Sci., vol. 6, no. Icmpc, pp. 656–665, 2014.      

21- C. D. Cox, B. T. Gibson, D. R. Delapp, A. M. Strauss, and G. E. Cook, “Technical paper A method for double-sided friction stir spot welding,” J. Manuf. Process., vol. 16, no. 2, pp. 241–247, 2014.

22- F.Zarghani, S.M.Mosavizade. Effect of dwell time on the microstructure and mechanical properties of projection friction stir spot welded 2024Aluminium Alloy. Iran International Aluminum Conference IIAC 2016.           
 

23- Zhengwei.Li,Yumei Yue,Shude Ji,Chai Peng,Ling Wang, "Optimal design of theread geometery and its performance in friction stir spot welding." Materials and design, vol 94,pp 368-376,2016.

24- Ashu Grag,.Anirban Bhattachaty."On lap shear strength of friction stir spot welded AA6061 alloy" Vol 26, pp 203-215,2017.

25- Y. F. Sun, H. Fujii, N. Takaki, and Y. Okitsu, “Microstructure and mechanical properties of dissimilar Al alloy / steel joints prepared by a flat spot friction stir welding technique,” Mater. Des., vol. 47, pp. 350–357, 2013.  

26- M. K. Bilici and A. I. Yukler, “Effects of welding parameters on friction stir spot welding of high density polyethylene sheets,” Mater. Des., vol. 33, pp. 545–550, 2012.

27- M. Paidar, A. Khodabandeh, M. L. Sarab, and M. Taheri, “Effect of welding parameters (plunge depths of shoulder, pin geometry, and tool rotational speed) on the failure mode and stir zone characteristics of friction stir spot welded aluminum 2024-T3 sheets,” J. Mech. Sci. Technol., vol. 29, no. 11, pp. 4639–4644, 2015.