Statistical Analysis and Optimization of the Yield Strength and Hardness of Surface Composite Al7075/Al2O3 Produced by FSP via RSM and Desirability Approach

Document Type: Research Paper


1 Faculty of Mechanical and Mechatronics Engineering, Shahrood University of Technology, Shahrood, Iran

2 Department of Mechanical Engineering, Malayer University, Malayer, Iran



In order to improve the properties of aluminum and its alloys, some various approaches (e.g. reduction of grain size, addition of alloying elements and composite manufacturing) have been considered. Among all these processes, the use of solid-state processes such as the friction stir processing (FSP) is highly convenient to create surface composites at temperatures below the melting point. Therefore, in this research, considering the FSP’s ability as a thermo-mechanical process and its advantages in the production of surface composites, the Al7075 surface composites were produced using reinforcing particles (Al2O3) and based on the FSP process in accordance with the design of experiments (DOE) approach. So, the response surface methodology (RSM) was selected as the experiment design method and variable factors such as: tool rotational speed, tool feed rate, diameter of tool shoulder and size of reinforcing particles were determined as the input variables. Statistical analysis and optimization of those parameters which affect the mechanical properties (yield strength and hardness) of surface composite Al7075/Al2O3 were performed. The results of the ANOVA and regression analysis of the experimental data approved the accuracy of regression equations and showed that the linear, interactional and quadratic terms of the input variables affect the yield strength and hardness of the composite specimens. Also, the optimal condition of the input variables was determined using the desirability method. In addition to the high values of desirability function (0.835, 0.822, 0.764), it could be found that the procedure of optimization has well fulfilled the pre-determined targets. In addition, the optimal condition has been confirmed by implementing the verification test.


[1] A. Heinz, A. Haszler, C. Keidel, S. Moldenhauer, R. Benedictus, W. S. Miller, Recent development in aluminium alloys for aerospace applications, Materials Science and Engineering: A 280 (1) (2000) 102-107.
[2] J. C. Williams, E. A. Starke, Progress in structural materials for aerospace systems, Acta Materialia 51 (19) (2003) 5775-5799.
[3] A. Esmaeili, M. H. Shaeri, M. Talafi Noghani, A. Razaghian, Fatigue behavior of AA7075 aluminium alloy severely deformed by equal channel angular pressing, Journal of Alloys and Compounds 757 (2018) 324-332.
[4] J. F. Li, Z. W.Peng, C. X. Li, Z. Q. Jia, W. J. Chen, Z. Q. Zheng, Mechanical properties, corrosion behaviors and microstructures of 7075 aluminium alloy with various aging treatments, Transactions of Nonferrous Metals Society of China 18 (4) (2008) 755-762.
[5] A. K. Shrivastava, K. K. Singh, A. R. Dixit, Tribological properties of Al 7075 alloy and Al 7075 metal matrix composite reinforced with SiC, sliding under dry, oil lubricated, and inert gas environments, Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 232 (6) (2018) 693-698.
[6] T. Knych, A. Mamala, W. Ściężor, Effect of selected alloying elements on aluminium physical properties and its effect on homogenization after casting, Materials Science Forum 765 (2013) 471-475.
[7] A. Rosochowski, Processing metals by severe plastic deformation, Solid State Phenomena 101-102 (2005) 13-22.

[8] A. Baradeswaran, A. Elaya Perumal, Wear and mechanical characteristics of Al 7075/graphite composites, Composites Part B: Engineering 56 (2014) 472-476.
[9] M. S. Tsai, P. L. Sun, P. W. Kao, C. P. Chang, Influence of severe plastic deformation on precipitation hardening in an Al-Mg-Si alloy: Microstructure and mechanical properties, Materials Transactions 50 (4) (2009) 771-775.
[10] K. Wawer, M. Lewandowska, A. Wieczorek, E. C. Aifantis, M. Zehetbauer, K. J. Kurzydlowski, Grain refinement in 7475 aluminum alloy via high pressure torsion and hydrostatic extrusion, Kovove Materialy-Metallic Materials 5 (2009) 325-332.
[11] M. Sarkari Khorrami, M. Kazeminezhad, A. H. Kokabi, Microstructure evolutions after friction stir welding of severely deformed aluminum sheets, Materials & Design 40 (2012) 364-372.
[12] W. M. Thomas, Friction stir butt welding, Int. Patent No. PCT/GB92/02203 (1991).
[13] M. Paidar, A. Asgari, O. O. Ojo, A. Saberi, Mechanical properties and wear behavior of AA5182/WC nanocomposite fabricated by friction stir welding at different tool traverse speeds, Journal of Materials Engineering and Performance 27 (2018) 1714.
[14] R. S. Mishra, M. W. Mahoney, S. X. McFadden, N. A. Mara, A. K. Mukherjee, High strain rate superplasticity in a friction-stir processed 7075 Al alloy, Scr. Mater, 41 (1999) 163-168.
[15] A. Jaferi, Z. Sadeghian, B. Lotfi, Application of Friction Stir Processing (FSP) as a Cladding Method to Produce AA2024-AA1050 Multi-layer Sheets, Iranian Journal of Materials Forming 6 (2) (2019) 20-29.
[16] S. Mironov, Y. S. Sato, H. Kokawa, Nanocrystalline titanium, Chapter 4: Friction-stir processing, Elsevier, ISBN 9780128145999 (2019) 55-69.
[17] S. Gholami, E. Emadoddin, M. Tajally, E. Borhani, Friction stir processing of 7075 Al alloy and subsequent aging treatment, Transactions of Nonferrous Metals Society of China 25 (2015) 2847-2855.
[18] R. Abrahams, J. Mikhail, P. Fasihi, Effect of friction stir process parameters on the mechanical properties of 5005-H34 and 7075-T651 aluminium alloys, Materials Science and Engineering: A 751 (2019) 363-373.
[19] V. R. Rao, N. Ramanaiah, M. M. M. Sarcar, Fabrication and investigation on properties of TiC reinforced Al7075 metal matrix composites, Applied Mechanics and Materials 592-594 (2014) 349-353.
[20] S. K. Josyula, S. K. R. Narala, A brief review on manufacturing of Al-TiC MMC, Advanced Materials Research 980 (2014) 62-68.
[21] R. S. Mishra, Z. Y. Ma, Friction stir welding and processing, Materials Science and Engineering: R: Reports 50 (1-2) (2005) 1-78.
[22] V. Sharma, U. Prakash, B. V. Manoj Kumar, Surface composites by friction stir processing: A review, Journal of Materials Processing Technology 224 (2015) 117-134.
[23] S. Ahmadifard, Sh. Kazemi, A. Heidarpour, Fabrication of Al5083/TiO2 surface composite by friction stir process and investigating its microstructural, mechanical and wear properties, Modares Mechanical Engineering 15 (12) (2015) 55-62 (in Persian).
[24] S. Ahmadifard, M. Roknian, T. Tinati Seresht, Sh. Kazemi, Fabrication of hybrid nanocomposite Al2024/Gr/ZrO2 via FSP and evaluation effect role of hybrid ratio in mechanical and wear properties, Modares Mechanical Engineering 16 (6) (2016) 119-126 (in Persian).
[25] N. Arun Babu, B. Balu naik, B. Ravi, G. Rajkumar, Process parameter optimization for producing AA7075/WC composites by friction stir welding, Materials Today: Proceedings 5 (2018) 18992-18999.
[26] S. Kumar, A. Kumar, C. Vanitha, Corrosion behaviour of Al 7075 /TiC composites processed through friction stir processing, Materials Today: Proceedings 15 (2019) 21-29.
[27] H. A. Deore, J. Mishra, A. G. Rao, H. Mehtani, V. D. Hiwarkar, Effect of filler material and post process ageing treatment on microstructure, mechanical properties and wear behaviour of friction stir processed AA 7075 surface composites, Surface and Coatings Technology 374 (2019) 52-64.
[28] M. Moradi, H. Arabi, A. F. H. Kaplan, An experimental investigation of the effects of diode laser surface hardening of AISI 410 stainless steel and comparison with furnace hardening heat treatment, Journal of the Brazilian Society of Mechanical Sciences and Engineering 41 (434) (2019) 1-11.
[29] D. C. Montgomery, Design and analysis of experiments, 9th edition, John Wiley & Sons, ISBN (2017) 978-1-119-11347-8.

[30] R. H. Myers, D. C. Montgomery, C. M. Anderson-Cook, Response surface methodology: process and product optimization using designed experiments, 4th edition, John Wiley & Sons, ISBN (2016) 978-1-118 91601-8.
[31] M. Vahdati, R. Mahdavinejad, S. Amini, M. Moradi, Statistical analysis and optimization of factors affecting the surface roughness in UVaSPIF process using response surface methodology, Journal of Advanced Materials and Processing 3 (1) (2015) 15-28.
[32] M. Moradi, M. KaramiMoghadam, High power diode laser surface hardening of AISI 4130; statistical modelling and optimization, Optics & Laser Technology 111 (2019) 554-570.
[33] A. Khorram, A. Davoodi Jamaloei, M. Paidar, X. Cao, Laser cladding of Inconel 718 with 75Cr3C2 + 25 (80Ni20Cr) powder: Statistical modeling and optimization, Surface and Coatings Technology 378 (2019) 124933.
[34]Design Expert software, version 11,
[36] AMSH6088: Heat Treatment of Aluminum Alloys - SAE International,
[37] M. Vahdati, R. Mahdavinejad, S. Amini, Statistical Analysis and optimization of factors affecting the spring-back phenomenon in UVaSPIF process using response surface methodology, ADMT Journal 8 (1) (2015) 13-23.
[38] M. Moradi, H. Arabi, M. Shamsborhan, Multi-objective optimization of high power diode laser surface hardening process of AISI 410 by means of RSM and desirability approach, Optik 202 (2020).