Yarı katı şekillendirilmiş AlSi12 alüminyum alaşımında Ag ilavesinin mikroyapıya etkisinin incelenmesi

Bu çalışmanın temel amacı yarı katı halde şekillendirilmiş AlSi12 alaşımına eser miktarda Ag elementi ilavesinin malzemenin mikroyapısına ve mekanik özelliklerine etkilerini ortaya koymaktır. Yarı katı halde şekillendirmenin intermetalik morfolojisi, Si oluşumu ve küresel α-Al morfolojileri üzerinde önemli bir etkiye sahip olduğu sonucuna varılmıştır. İntermetalikler yarı katı halde şekillendirme esnasında kırılmaktadır. Ayrık Si partikülleri hem yarı katı hem de tikso şekillendirmede gözlenmiştir ve mekanik özelliklere önemli katkısı olmuştur.

Investigation of microstructure effect of Ag addition in Thixo forming AlSi12 aluminum alloy

The main objective of this study is to reveal the effect of the Thixo process on the microstructure and mechanical properties of the AlSi12 alloy with trace amounts of silver. It is concluded that Thixo has an important effect on the morphology of intermetallics and Si formation, as well as globular α-Al morphology. The intermetallics have been fractured during thixo. It is believed that the fine distribution of the intermetallics is one mechanism for the improved mechanical properties of Thixo alloys. The discrete Si particles have been observed during both isothermal heating and Thixo and have an important effect on mechanical properties.

Keywords:

AlSi alloys, intermetallic phases, mechanical properties Ag addition, thixo forming,

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Bolouri, A. ve Kang, C.G., Characteristics of thixoformed A356 aluminum thin plates with microchannels, Materials Characterization, 82, 86–96, (2013).
Bolouri, A., Bae J.W. ve Kang C.G., Tensile properties and microstructural characteristics of indirect rheoformed A356 aluminum alloy. Materials Science and Engineering A, 562(1), 1-8, (2013).
Chung G.K., Chul K. J. ve Amir B., Semisolid forming of thin plates with microscale features , Procedia Engineering, 81, 63-73, (2014).
Kim, W.Y., Kang, C.G. ve Kim, B.M., The effect of the solid fraction on rheological behavior of wrought aluminium alloys in incremental compression experiments with a closed die, Materials Science and Engineering A, 44, 1-10, (2007).
Hekmat-Ardakan, A. ve Ajersch, F., Effect of isothermal ageing on the semi-solid microstructure of rheoprocessed and partially remelted of A390 alloy with 10% Mg addition, Materials Characterization, 61, 778–85, (2010).
Flemings, M.C., Behavior of metal alloys in the semi-solid state, Metal. Trans. A, 22A, 952-981, (1991).
Wang, J.J., Phillion, A.B. ve Lu, G.M., Development of a visco-plastic constitutive modeling for thixoforming of AA6061 in semi-solid state, Journal of Alloys and Compounds, 609, 290-295, (2014).
Zhang, L., Liu, Y.B., Cao, Z.Y., Zhang, Y.F. ve Zhang, Q.Q., Effects of isothermal process parameters on the microstructure of semisolid AZ91D alloy produced by SIMA, Journal of Materials Processing Technology, 209, 792-797, (2009).
Wang, S.C., Zhou, N., QI W.J. ve Zheng, K.H., Microstructure and mechanical properties of A356 aluminum alloy wheels prepared by thixo-forging combined with a low superheat casting process, Trans. Nonferrous Met. Soc., 24, 2214-2219, (2014).
Banerjee, S., Robi, P.S., Srinivasan, A. ve Lakavath, P.K., Effect of trace additions of Sn on microstructure and mechanical properties of Al–Cu–Mg alloys. Materials & Design, 31(8), 4007-4015, (2010).
Mrówka-Nowotnik, G., Sieniawski, J. ve Wierzbińska, M.. Analysis of intermetallic particles in AlSi1MgMn aluminium alloys, Journal of Achievements in Materials and Manufacturing Engineering 20, 155-158, (2007).
Mrówka-Nowotnik, G., Sieniawski, J. ve Wierzbińska, M.. Intermetallic phase particles in 6082 aluminium alloy, Archives of Materials Science and Engineering 282, 69-76, ( 2007).
Wierzbińska, M. ve Mrówka-Nowotnik, G., Identification of phase composition of AlSi5Cu2Mg aluminium alloy in T6 condition, Archives of Materials Science and Engineering, 30(2), 85-88, ( 2008).
Zajac, B., Bengtsson, Ch. ve Jönsson,, Influence of cooling after homogenization and reheating to extrusion on extrudability and final properties of AA 6063 and AA 6082 alloys, Materials Science Forum, 396-402, 675-680 ( 2002).
Zhen, L. ve Kang, S.B., DSC analyses of the precipitation behavior of two Al-Mg-Si alloys naturally aged for different times. Materials Letters. 37, 349-353, (1998).
Shabestari, S.G. ve Ghanbari, M., Effect of plastic deformation and semisolid forming on iron–manganese rich intermetallics in Al–8Si–3Cu–4Fe–2Mn alloy. Journal of Alloys and Compounds, 508(2), 315-319, (2010).
Irizalp, S.G., Saklakoğlu, N., Effect of Fe-rich intermetallics on the microstructure and mechanical properties of thixoformed A380 aluminum alloy. Engineering Science and Technology, an International Journal, 17(2), 58-62, (2014).
Elgallad, E.M., Samuel, A.M., Samuel, F.H. ve Doty, H.W., Effects of additives on the microstructures and tensile properties of new Al-Cu based alloy intended for automotive castings. AFS Transactions , American Foundry Society, Schaumburgi IL USA, 10-42, (2010).
Türker, A., ETİAL 171 Alaşımının yarı katı halde şekillendirilebilirliğine eser miktarda Ag ilavesinin etkisinin incelenmesi, Celal Bayar Üniversitesi Fen Bilimleri Enstitüsü Makine Mühendisliği, Doktora Tezi, (2011).
Ittipon, D., Semi-solid processing of hypereutectic aluminum-silicon alloys, Massachusetts Institute of Technology, Mater Sci Eng, MIT, (1996).
Saklakoglu, N. ve Turker, A., Characterization of thixoformed AlSi12 alloy with the addition of trace amounts of silver, World Academy of Science, Engineering and Technology International Journal of Aerospace and Mechanical Engineering, 10(7), (2016).
Legoretta, E.C., Atkinson H.V. ve Jones H., Cooling slope casting to obtain thixotropic feedstock, Proceedings of the 5th Decennial International Conference on Solidification Processing, 23-25 July, Sheffield, UK. (2007).
Birol, Y., A357 thixoforming feedstock produced by cooling slope casting, Journal of Materials Processing Technology,186, 94–101, (2007).
Haga, T. ve Kapranos, P., Simple rheocasting processes, Journal of Materials Processing Technology, 130–131, 594–598, (2002).
Haga, T. ve Suzuki, S., Casting of aluminium alloy ingots for thixoforming using a cooling slope, Journal of Materials Processing Technology, 118, 169–172, (2001).
Türker, A. ve Saklakoglu, N., The influence of Ag content on the microstructure and intermetallic phases of AlSi12 alloy, International Journal of Cast Metals Research, 129-133, (2013).