Modeling and optimization of precipitation hardening heat treatment factors of Al2024 alloy using a two-level full factorial design
محورهای موضوعی : Surface EngineeringMaryam Moazeni 1 , Ali Ashrafi 2 , Ali Zeinal-Hamadani 3
1 - Department of Materials Engineering, Isfahan university of technology,Isfahan,Iran
2 - Department of Materials Engineering, Isfahan university of technology,Isfahan,Iran
3 - Department of Industrial & Systems Engineering, Isfahan University of Technology, Isfahan, Iran.
کلید واژه: Heat treatment, Hardness, optimizing, Aluminum 2024 alloy, full factorial design,
چکیده مقاله :
In the current study, the sources of variation in the mean hardness value of heat treated aluminum 2024 samples were identified by using metallurgical study and design of experiment methodology (full factorial method). Hardness measurements and microstructural investigations of the samples were carried out using Brinell hardness test and optical microscopy, respectively. The effects of several control factors including solution treatment temperature, aging temperature and also aging time on the hardness were evaluated. The main and interactions effects of the factors were studied by means of analysis of variance (ANOVA) technique. Moreover, the best model which can estimate the hardness of heat treated Al2024specimens was found whereas the aging temperature and interaction of aging time and aging temperature have significant effects on the hardness value. Finally, the optimum conditions of the factors were found for obtaining conditions of heat treatment to maximize hardness of the sample according to results of designing and regarding statistical factors. The Al2024 alloy with the hardness 133 Brinell was assessed as the optimum hardness during heat treatment conditions including solution treatment temperature of 530 °C, aging temperature of 180 °C and aging time of 12 hr value that it has good agreement with the estimated value by the model i.e. about131 Brinell.
1. J. L. Brandt, “Properties of pure aluminum”, ASM international, 1984.
2. J. R. Davis. “Aluminum and aluminum alloys”, ASM Specialty Handbook, 1957.
3. S. P. Ringer, K. Hono, I. J. Polmear, T. Sakurai, “Precipitation processes during the early stages of ageing in Al-Cu-Mg Alloys”, Appl. Surf. Sci. Vol. 94, 1996,
pp. 253–260.
4. Y. Gefen, M. Rosen, A. Rosen, “Aging phenomena in Duraluminum 2024 studied by resistometry and hardness”, Mater. Sci. Eng. Vol. 8, 1971, pp. 181-188.
5. A. Charai, T. Walther, C. Alfonso, A. M. Zahra, C. Y. Zahra, “Coexistence of clusters, GPB zones, S″-, S′- and S-phases in an Al–0.9% Cu–1.4% Mg alloy”, Acta Mater. Vol. 48, 2000, pp. 2751–2764.
6. S. P. Ringer, T. Sakurai, I. J. Polmear, “Origins of hardening in aged Al-Gu-Mg-(Ag) alloys”, Acta Mater. Vol. 45, 1997, pp. 3731–3744.
7. M. N. Cavalli, V. Mandava, “Effect of temperature and aging time on 2024 aluminum behavior”, Proc. the 6th International Congress and Exposition, Orlando, Florida-USA, 2008, pp. 674-687.
8. T. Lundstedt, E. Seifert, L. Abramo, B. Thelin, A. Nystrom, J. Pettersen, R. Bergman, “Experimental design and optimization”,Chemom.Intell. Lab. Syst. Vol. 42, 1998, pp. 3–40.
9. A. C. Tamhane, “Statistical analysis of designed experiments: theory and applications”, 1th ed, Wiley series in probability and statistics, 2009.
10. S. A. Sayyad, B. P. Panda, S. Javad, M. Ali, “Optimization of nutrient parameters for lovastain production by Monascus MTCC 369 under submerged fermentation using response surface methodology”, Appl. Microbiol. Biotechnol. Vol. 73, 2006,
pp. 1054–1058.
11. R. Gottipati, S. Mishra, “Process optimization of adsorption of Cr (VI) on activated carbons prepared from plant precursors by a two-level full factorial design”, Chem. Eng. J. 160, 2010,
pp. 99–107.
12. T. Golshani, E. Jorjani, S. ChehrehChelgani, S. Z. Shafaei, Y. HeidariNafechi. “Modeling and process optimization for microbial desulfurization of coal by using a two-level full factorial design”. Int. J. Mining Sci. Technol. Vol. 23, 2013, pp. 261-265.
13. H. Jafaria, M. H. Drisa, A. R. Shayganpour, “Evaluation of significant manufacturing parameters in lost foam casting of thin-wall Al–Si–Cu alloy using full factorial design of experiment”, T. Nonferr. Metal Soc. Vol. 23, 2013, pp. 2843-2851.
14. R. Fontanaa, G. Pistone, M. P. Rogantin, “Classification of two-level factorial fractions”, J. Stat. Plan. Infer. Vol. 87, 2000, pp. 149-172.
15. D. C. Mongomery, “Design and analysis of experiments”, 5thed, John Wiley and Sons. INC, 1997.
