Optimization of Process Parameters for Friction Stir Welding of Cast Alloy AA7075 by Taguchi Method

Authors: Dhairya Partap Sing, Vikram Singh, Sudhir Kumar

Abstract:

This investigation proposes Friction stir welding technique to solve the fusion welding problems. Objectives of this investigation are fabrication of AA7075-10%wt. Silicon carbide (SiC) aluminum metal matrix composite and optimization of optimal process parameters of friction stir welded AA7075-10%wt. SiC Composites. Composites were prepared by the mechanical stir casting process. Experiments were performed with four process parameters such as tool rotational speed, weld speed, axial force and tool geometry considering three levels of each. The quality characteristics considered is joint efficiency (JE). The welding experiments were conducted using L₂₇ orthogonal array. An orthogonal array and design of experiments were used to give best possible welding parameters that give optimal JE. The fabricated welded joints using rotational speed of 1500 rpm, welding speed (1.3 mm/sec), axial force (7 k/n) of and tool geometry (square) give best possible results. Experimental result reveals that the tool rotation speed, welding speed and axial force are the significant process parameters affecting the welding performance. The predicted optimal value of percentage JE is 95.621. The confirmation tests also have been done for verifying the results.

Keywords: Metal matrix composite, axial force, joint efficiency, rotational speed, traverse speed, tool geometry.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.3455627

References:

[1] Seo and Kang, Effects of Hot Extrusion through a Curved Die on the Mechanical Properties of SiCp/Al Composites Fabricated by Melt Stirring, Compos. Sci. Technol., 1999, 59, p 643–654
[2] Kim and Lee, Chongmin Kim and Formability of evaluation of friction stir welded 6111-T4 sheet with respect joining material direction. International Journal of Mechanical Science, doi:10. 1016/j.ijmecsci. 2010. Maharashtra Institute of Technology, India, 2009.01.00.
[3] Clyne and Withers, An Introduction to Metal Matrix Composites, Cambridge Solid State Science Series, Cambridge University Press, 1995, p 1–10
[4] Ralph and Lee, The Processing of Metal Matrix Composites—An Overview, J. Mater. Process. Technol, 1997, 63, p 339–353
[5] Masounave and Hamel, Fabrication of Particulate Reinforced Metal Composites, ASM International, Montreal, Que, Canada,September, 1990, p 79-86.
[6] Gaafer and Khalifa, Effect of tool rotational and welding speeds on micro-structural and mechanical characteristics of friction stir welded A319 cast Al alloy, Materials Science and Technology, 24(5): 553-559.
[7] Vijaya and Rao, Multi objective optimization of Friction Stir Welding Process Parameters on Aluminium Alloy AA6061 Using Taguchi Based Grey Relation Analysis 25, 1206-1212, 2010.
[8] Elangovan, and Balasubramanian, Influences of tool pin profile and tool shoulder diameter on the formation of friction stir processing zone in AA6061 aluminium alloy. Materials & Design 29: 362–373.
[9] Palanivel and Murugan, Influences of tool pin profile on the mechanical and metallurgical properties of friction stir welding of dissimilar aluminum alloys.2010, Int. Journal of Engg. Science and Technology 2(6): 2109–2115.
[10] Vijay, and Murugan, Influence of tool pin profile on the metallurgical and mechanical properties of friction stir welded Al–10 wt-% TiB2 metal matrix composite. Materials and Design 2010,31: 3585–3589.
[11] Azimzadegan and Serajzadeh, An investigation into microstructures and mechanical properties of AA7075-T6 during friction stir welding at relatively high rotational speeds
[J].Journal of Materials Engineering Performance, 2010, 19(9): 1256−1263.
[12] Elangovan and Balasubramanian, Predicting tensile strength of friction stir welded AA6061 aluminum alloy joints by a mathematical model
[J]. Materials & Design, 2009, 30(1): 188−193.
[13] Sundaram and Murugan, Tensile behavior of dissimilar friction stir welded joints of aluminium alloys (J). Materials & Design, 2010, 31(9): 4184−4193.
[14] Brechet, Y,(1991),Axta Metallurgical materials 39,1781.
[15] P.J. Ross, “Taguchi Technique for Quality Engineering”, New York: McGraw-Hill book company, 1988.