Soğuk İşlemle (CW) İşlenen AA 6061 T6 Alüminyum alaşımının Mekanik Özelliklerinin Gelişimi

Yıl 2023, Cilt: 4 Sayı: 1, 30 - 35, 21.06.2023

Debıh Ali

https://doi.org/10.53525/jster.1233386

Öz

Özet – Nano ölçekli tane boyutu küçültme (UFG), 6000 serisi alüminyum alaşımlarının mekanik özelliklerini iyileştirmek için yapısal çöktürme, gerinim sertleştirme veya soğuk iş sertleştirme yoluyla üç uygun yöntemden biridir. Soğuk işleme için artık (ECAP - PC), (CEEA), (THP), (MM), (ARB), (CW) gibi çeşitli teknikler mevcuttur. Sıkıştırma yüksek presleme (CW-CHP) ile soğuk işlem, malzemenin sertleşme davranışına bağlı olarak birkaç döngüde uygulanabilir. Küçültme oranları (%3.5, 10,18.8 ve %28) ile dört geçişli Sever plastik deformasyona sahip silindirik bir haddeleme makinesinin (CW-CHP) tarafından üretilen tanelerin metrik olmayan boyutunun, malzemenin mekanik davranışına etkisi 6061 T6 alaşımı, nihai gerilme mukavemeti (Rm), akma mukavemeti (Rp0., gerinim sertleştirme kapasitesi SHC (Rm-Rp0.2), iş sertleştirme katsayısı n', 'iş sertleştirme K' modülü belirlenerek analiz edilmiştir. Numune kesitlerinin küçültülmesi ve sonuç olarak birinci ve ikinci pasoda tane boyutunun küçültülmesi ile iş sertleştirme oranındaki artış, alaşımın mekanik özelliklerini maksimum değerlere ve daha sonra çatlağın mevcudiyetini iyileştirir. başlatma, mekanik özelliklerin orta derecede azalmasına katılır.

Anahtar Kelimeler

AA 6061T6, Cold working, Ultrafine grain, Mechanical properties, Sever plastic deformations

Evolution of Mechanical Properties of an AA 6061 T6 Aluminum alloy Processed by Cold Working (CW)

Öz

Nano scale grain size reduction (UFG) is one of three suitable methods for improving the mechanical properties of 6000 series aluminum alloys, by structural precipitation, strain hardening or by cold work hardening. For the cold working, several techniques are now available such as (ECAP - PC), (CEEA), (THP), (MM), (ARB), (CW). Cold work by compression high pressing (CW-CHP) can be applied in several cycles depending on the hardening behavior of the material. The influence of the nonmetric size of the grains produced by the (CW-CHP) of a cylindrical rolling machine with four passes of Sever plastic deformation with reduction ratios of (3.5, 10,18.8 and 28%), on the mechanical behavior of the alloy 6061 T6, was analyzed by determining the ultimate tensile strength (Rm), yield strength (Rp0.2, the strain hardening capacity SHC (Rm-Rp0.2), the work hardening coefficient n', the modulus of 'work hardening K' . The increase in the rate of work hardening by the reduction of the sample sections and consequently the reduction of the grain size at the first and the second pass, improves the mechanical properties of the alloy to the maximum values, and then the presence of crack initiation participates to the moderate decrease of the mechanical properties.

Anahtar Kelimeler

AA 6061T6, Cold working, Ultrafine grain, Mechanical properties, Sever plastic deformations

Kaynakça

• [1] Bahman Mirzakhania, Mostafa Mansourinejad, "Tensile properties of AA6061 in different designated precipitation hardening and cold working", Procedia Engineering 10 (2011) 136–140.
• [2] M. Abdulwahab , I.A. Madugu , S.A. Yaro , S.B. Hassan , A.P.I. Popoola , "Effects of multiple-step thermal ageing treatment on the hardness characteristics of A356.0-type Al–Si–Mg alloy", Materials and Design 32 (2011) 1159–1166.
• [3] Suttawan Imurai, Julatep Kajornchaiyakul , Chachana Thanachayanont, John T.H. Pearce and Torranin Chairuangsri, "Age Hardening and Precipitation Behavior of an Experimental Cast Al-Mg-Si Alloy Treated by T6 and T6I6 Heat Treatments", Chiang Mai J. Sci. 2010; 37(2) : 269-281, [4] X. fang, M. song, K. li and y. du, "Precipitation sequence of An Aged Al-Mg-Si Alloy", J. Min. Metall. Sect. B-Metall. 46 (2) B (2010), pp 171 – 180, http://dx.doi.org/10.2298/JMMB1002171F
• [5] M. Yu. Murashkin, E. V. Bobruk, A. R. Kilmam]etov, and R. Z. Valiev, "Structure and Mechanical Properties of Aluminum Alloy 6061 Subjected to Equal-Channel Angular Pressing in Parallel Channels". The Physics of Metals and Metallography, (2009), Vol. 108, No. 4, pp. 415–423.
• [6] L. W. Meyer , R. Schönherr , M. Hockauf, "Increasing strength, ductility and impact toughness of ultrafine-grained 6063 aluminium alloy by combining ECAP and a high-temperature short-time aging", Journal of Physics: Conference Series 240 (2010) 012123. doi:10.1088/1742-6596/240/1/012123.
• [7] M. A. Rekik, T. Makhlouf, N. Njah, "Evolution of microstructural and mechanical properties of an industrial 2017 Aluminium alloy processed by equal channel angular extrusion". IOP Conf. Series: Materials Science and Engineering 28 (2012) 012039. doi:10.1088/1757-899X/28/1/012039
• [8] T. Hausöl, H.W. Höppel and M. Göken: "Microstructure and mechanical properties of accumulative roll bonded aluminium alloy AA5754". Journal of Physics: Conference Series 240 (2010) 012128. doi:10.1088/1742-6596/240/1/012128
• [9] Genki Horii, Daisuke Terada and Nobuhiro Tsuji, "Strain hardening and softening in ultrafine grained Al fabricated by ARB process", Journal of Physics: Conference Series 240 (2010) 012114. doi:10.1088/1742-6596/240/1/012114
• [10] D. Ortiz, M. Abdelshehid, R. Dalton, J. Soltero, R. Clark, M. Hahn, E. Lee, W. Lightell, B. Pre[gger, J. Ogren, P. Stoyanov, and O.S. Es-Said, "Effect of Cold Work on the Tensile Properties of 6061, 2024, and 7075 Al Alloys". JMEPEG (2007) 16:515–520. DOI: 10.1007/s11665-007-9074-7
• [11] Michel Colombie, "Matériaux métalliques", Dunod, Paris 2001, 61, ( in French).
• [12]. Bineeth Benny, "Use of Hollomon Equation in Combination with Conventional Equation, for Finding Change in strain Hardening Exponent Value, among Differently Aged and Tensile tested Maraging Steel Samples", SSRG – IJMSE ) Volume 2 Issue 3, 2016, 6-7.
• [13] Haneen M. Saud and Mohammed A. Abdulrazzaq, "Study the effect of cold working on the mechanical properties of aluminum alloy 2024 T4", IOP Conf. Series: Materials Science and Engineering 928 (2020) 022125, doi:10.1088/1757-899X/928/2/022125
• [14] Marta Harniˇcárová, Jan Valíˇcek, Milena Kušnerová , Ivan Kopal , Miloslav Lupták , Rastislav Mikuš , Zdenˇek Pavelek , Martin Fabián and Vladimír Šepelák, "Structural and Mechanical Changes of AlMgSi0.5 Alloy during Extrusion by ECAP Method", Materials 2022, 15, 2020. https://doi.org/10.3390/ma15062020.
• [15] Abdulrahaman Shuaibu Ahmad, Wu Yunxin,Gong Hai1, Liu Lei, "Determination of the Effect of Cold Working Compression on Residual Stress Reduction in Quenched Aluminium Alloy 2219 Block", Journal of Mechanical Engineering 65(2019)5, 311-318, DOI:10.5545/sv-jme.2018.5938