Subscribe to our Newsletter and get informed about new publication regulary and special discounts for subscribers!

IJET > IJET Volume 18 > Effect of Section Size as a Measure of Cooling...
< Back to Volume

Effect of Section Size as a Measure of Cooling Rate on the Solidified Microstructure and Mechanical Properties of Sand-Cast Al-Si Eutectic Alloy

Full Text PDF


Several factors contribute to the development of structure and properties of aluminiumalloy castings. This study investigated the singular effect of cooling rate on the as-cast structure andmechanical properties of an aluminum-silicon eutectic alloy, keeping other factors such as pouringtemperature, melt treatments, physical and thermal properties of the mould, and alloy compositionconstant. The rate of cooling was varied by employing different casting section sizes, based on thevariation of rate of heat extraction given by solidification time as predicted by the Chvorinov’s rule.Four test bars of section sizes 10, 20, 30, and 40 mm respectively were cast in sand mould using thesame gating system. Spectrometric analysis of the alloy formulated revealed that it could be specifiedapproximately as Al-12.8Si-1.0Cu alloy. The study showed that as section size decreased from 40mm to 10 mm; the solidification time reduced (i.e. the cooling rate increased), the microstructure gotfiner, the silicon flakes became more uniformly distributed, and the mechanical properties generallyimproved. The tensile strength, ductility, and hardness all increased in the order of decreasing sectionsize, i.e. increasing cooling rate. The mechanical properties were found to be linearly correlated withsection size or cooling rate. Whereas the elongations were lower than values for pure aluminium, thestrength and hardness were significantly higher than values for the pure metal. It is concluded thatthe cooling rate modifies the microstructure and improves the mechanical properties of as-cast Al–Sieutectic alloys


International Journal of Engineering and Technologies (Volume 18)
U. Mark, "Effect of Section Size as a Measure of Cooling Rate on the Solidified Microstructure and Mechanical Properties of Sand-Cast Al-Si Eutectic Alloy", International Journal of Engineering and Technologies, Vol. 18, pp. 8-22, 2020
Online since:
April 2020

[1] Polmear, I.J., StJohn, D., Nie, J.F. & Qian, M. (2017): Light Alloys: Metallurgy of the Light Metals, (Fifth ed.). Oxford: Butter-Worth Heinemann. p.108–131.


[2] Elliott, R. (1997): Eutectic Solidification Processing; Crystalline and Glassy Alloys. Oxford: Butterworths Monographs in Materials.

[3] Higgins, R.A. & Bolton, W. (2015). Materials for Engineers and Technicians, (Sixth ed.); Oxford: Routledge, p.31, 32, 57–67, 127–138, 235–249.

[4] Asensio-Lozano, J &.Voort, G.V. (2015). The Al-Si Phase Diagram. Tech-Notes, Volume 5, Issue 1, p.1–5, Published by Buehler, A Division of Illinois Tool Works Inc.

[5] Robles-Hernandez, F.C., Ramírez, J.M.H. & Mackay, R. (2017). Al–Si Alloys: Automotive, Aeronautical, and Aerospace Applications. Cham, Switzerland: Springer International Publishing AG.


[6] Okorafor, O.E. (2004): Expendable Polystrene Pattern Cast Process: A Revolution in Foundry Technology, Inaugural Lecture Series 7 of FUTO, Owerri: FUTO Press. p.80.

[7] Onyemaobi, O.O. (2002): Mineral Resources Exploitation, Processing and Utilization – A Sine Qua Non for Nigeria's Metallurgical Industrial Development, Inaugural Lecture Series 5 of FUTO, Owerri: FUTO Press. p.48.

[8] Cottrell, A.H. (1995): An Introduction to Metallurgy, (Second ed.). London: The Institute of Metals, pp.177-189.

[9] Reif W. & Muller K. (1998). Improvement of Mechanical Properties of Al-Si-Cast Alloys by Grain Refinement and Modification. In R. Ciach (ed.), Advanced Light Alloys and Composites Berlin: Kluwer Academic Publishers., p.263–275.


[10] Abbaschian, G.R. Abbaschian, L. & Reed-hill, R.E. (2009): Physical Metallurgy Principles, (Fourth ed.). Connecticut: Cengage Learning, p.437–445.

[11] Porter, D.A., Easterling, K.E. & Sherif, M.Y. (2009). Phase Transformations in Metals and Alloys, (Third ed.), Florida: Taylor & Francis Group, p.220–227.

[12] Liu, N., Kang, G. & Liu, Z. (2012). Effect of Compound Modification on Microstructure and Properties of High Silicon Aluminum Alloy. Advanced Materials Research Vols. 476-478 p.114–117.


[13] Dang. B., Zhang, X., Chen, Y.Z., Chen, C.X., Wang, H.T. & Liu, F. (2016). Breaking through the strength–ductility trade-off dilemma in an Al-Si-based casting alloy. Nature Scientific Reports, 6:30874, p.1–10.


[14] Zhang, L.Y., Jiang, Y.H., Ma, Z., Shan, S.F., Jia, Y.Z., Fan, C.Z. & Wang, W.K. (2008). Effect of cooling rate on solidified microstructure and mechanical properties of aluminium-A356 alloy, Journal of Materials Processing Technology, 207: 107–111.


[15] Zhuo, L., Pang, S., Wang, H. & Zhang, T. (2010). Effect of cooling rate on microstructure and mechanical properties of rapidly solidified Al-based bulk alloys. Journal of Alloys and Compounds, 504S: S117–S122.


[16] Guzel, E., Yuksel, C., Bayrak, Y., Sen, O. & Ekerim, A. (2014). Effect of Section Thickness on the Microstructure and Hardness of Ductile Cast Iron. Metallography and Hardness Measurements, 56(4): 285–288.


[17] Sahu, S., Bhat, M.N., Kumar, A., Pratik, A. & Kumar, A. (2014). Effect of Section Thickness on the Microstructure and Hardness of Gray Cast Iron (A Simulation Study). International Journal of Engineering Research & Technology, 3(7): 35–40.

[18] Askeland, D.R. & Wright, W.J. (2016). The Science and Engineering of Materials, (Seventh ed.); Connecticut: Cengage Learning, p.305–330.

[19] ASTM International (2016). Standard Test Methods for Tension Testing of Metallic Materials: ASTM/E8E8M.37691.

[20] Shabestari, S.G. & Malekan, M. (2005). Thermal analysis study of the effect of the cooling rate on the microstructure and solidification parameters of 319 aluminum alloy. Canadian Metallurgical Quarterly, 44 (3): 305–312.


[21] Singh, R.K. Telang, A. & Das, S. (2016). Microstructure and Mechanical Properties of Al-Si Alloy in As-cast and Heat-Treated Condition. American Journal of Engineering Research, 5(3):133–137.

[22] Suareza, M.A., Figueroab,I., Cruza, A. Hernandeza, A. & Chavez, J.F. (2012). Study of the Al-Si-X System by Different Cooling Rates and Heat Treatment. Materials Research. 15(5): 763–769.

[23] Thompson, S., Cockcroft, S.L. & Wells, M.A. (2004). Effect of cooling rate on solidification characteristics of aluminium alloy AA 5182. Materials Science and Technology, 20: 497–504.


[24] Tian, L., Guo, Y., Li, J., Xia, F., Liang, M. & Bai, Y. (2018). Effects of Solidification Cooling Rate on the Microstructure and Mechanical Properties of a Cast Al-Si-Cu-Mg-Ni Piston Alloy. MDPI Materials, 11, 1230; p.2–9.


[25] Han, S.Z., Choi, E., Park, H.W., Lim, S.H., Lee, J., Ahn, J.H., Hwang, N-M. & Kim, K. (2017). Simultaneous increase in strength and ductility by decreasing interface energy between Zn and Al phases in cast Al-Zn-Cu alloy. Nature Scientific Reports, 7: 12195, p.1–8.


[26] Rao, P.N., Kaurwar, A. Singha, D. & Jayaganthana, R. (2014). Enhancement in Strength and Ductility of Al-Mg-Si alloy by Cryo-rolling followed by Warm rolling. Procedia Engineering, 75 :123–128.


[27] Liu, F.C., Yang, Z.N., Zheng C.L. & Zhang, F.C. (2011). Simultaneously improving the strength and ductility of coarse-grained Hadfield steel with increasing strain rate. Scripta Materiala, 66: 431–434.


[28] Anilchandra, A.R., Arnberg, L., Bonollo, F., Fiorese, E. & Timelli, G. (2017). Evaluating the Tensile Properties of Aluminum Foundry Alloys through Reference Castings—A Review. MDPI Materials,10, 1011; p.1–12.


[29] Caceres, C.H., Svensson, L. & Taylor, J.A. (2003). Strength–Ductility Behaviour of Al-Si-Cu-Mg Casting Alloys in T6 Temper. International Journal of Cast Metals Research, 15:531–543.

Show More Hide
Cited By:
This article has no citations.