Fabrication Characteristics and Mechanical Behavior of Fly Ash-Alumina Reinforced Zn-27Al Alloy Matrix Hybrid Composite Using Stir-Casting Technique

Authors: Oluwagbenga B. Fatile, Felix U. Idu, Olajide T. Sanya

Abstract:

This paper reports the viability of developing Zn-27Al alloy matrix hybrid composites reinforced with alumina, graphite and fly ash (solid waste bye product of coal in thermal power plants). This research work was aimed at developing low cost-high performance Zn-27Al matrix composite with low density. Alumina particulates (Al2O3), graphite added with 0, 2, 3, 4 and 5 wt% fly ash were utilized to prepare 10wt% reinforcing phase with Zn-27Al alloy as matrix using two-step stir casting method. Density measurement, estimated percentage porosity, tensile testing, micro hardness measurement and optical microscopy were used to assess the performance of the composites produced. The results show that the hardness, ultimate tensile strength, and percent elongation of the hybrid composites decrease with increase in fly ash content. The maximum decrease in hardness and ultimate tensile strength of 13.72% and 15.25% respectively were observed for composite grade containing 5wt% fly ash. The percentage elongation of composite sample without fly ash is 8.9% which is comparable with that of the sample containing 2wt% fly ash with percentage elongation of 8.8%. The fracture toughness of the fly ash containing composites was however superior to those of composites without fly ash with 5wt% fly ash containing composite exhibiting the highest fracture toughness. The results show that fly ash can be utilized as complementary reinforcement in ZA-27 alloy matrix composite to reduce cost.

Keywords: Fly ash, hybrid composite, mechanical behaviour, stir-cast.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1109217

References:

[1] B.O. Fatile, J.I. Akinruli, and A.A. Amori, “Microstructure and mechanical behaviour of stir-cast Al-Mg-Sl alloy matrix hybrid composite reinforced with corn cob ash and silicon carbide”, Int. j. of Eng. and Tech. Innovation, vol. 4, no. 4, pp. 251-259, 2014.
[2] K.K. Alaneme, B. O. Fatile, and J.O. Borode, “Mechanical and corrosion behaviour of Zn‐27Al based composites reinforced with groundnut shell ash and silicon carbide”, Tribology in Industry, vol. 36, no 2, pp. 195-203, 2014.
[3] M. Babic, A. Vencl, S. Mitrovic, and I. Bobic, “Influence of T4 heat treatment on tribological behavior of Za-27 alloy under lubricated sliding condition”, Tribology Letters, vol. 36, no.2, 125-134, 2009.
[4] R.J. Barnhurst, and S. Beliste, Corrosion properties of Zamak and ZA Alloys. Quebec, Canada: Noranda Technology Centre, 1992.
[5] S.C. Sharma, B.M. Girish, R. Kamath, B.M. and Satish, “Graphite particles reinforced ZA‐27 alloy composite materials for journal bearing applications”, Wear, vol. 219, no. 2, pp. 162 -168, 1998.
[6] B. Bobic, S. Mitrovic, M. Bobic, and I. Bobic, “Corrosion of Aluminium and Zinc‐Aluminium alloys based metal matrix composites”, Tribology in Industry, vol. 31, no. 3&4, pp. 44‐52, 2009.
[7] E.J. Kubel, “Expanding horizons for ZA alloys”, Advanced Materials and Processes, vol. 7, pp. 51‐57, 1987.
[8] C.H. Prakash, and R.D. Pruthviraj, “Microstructural studies of cast Zinc - Aluminum-Sic-Graphite hybrid composites”, Research J. of Chemical Sciences, vol. 1, no. 6, 88-90.
[9] K.K. Alaneme, B. O. Ademilua, and M. O. Bodunrin, “Mechanical and corrosion behaviour of bamboo leaf ash – Silicon Carbide hybrid reinforced Aluminium based matrix composites”, Tribology in Industry, vol. 35, no. 1, pp. 25‐35, 2013.
[10] O.A. Olugbenga, and A.A. Akinwole, “Characteristics of bamboo leaf ash stabilization on lateritic soil in highway construction”, Int. J. of Eng. and Tech., vol. 2, no.4, pp. 212‐219, 2010.
[11] K.K. Alaneme, A.O. Aluko, “Production and age hardening behaviour of borax pre mixed SiC reinforced Al-Mg-Si alloy composites developed by double stir casting technique”, The West Indian J. of Eng., vol. 34, no. 1‐2, pp. 80 – 85, 2012.
[12] T. S. Kiran, M.P. Kumar, S. Basavarajappa, and B. M. Vishwanatha, “Mechanical properties of as- cast za-27/gr/sicp hybrid composite for the application of journal bearing”, J. of Eng. Sci. and Tech., vol. 8, no. 5, 557 -565, 2013.
[13] K. K. Alaneme”, Mechanical behaviour of cold deformed and solution heat-treated alumina reinforced AA 6063 composites”, J. of European Ceramic. Society, vol. 35, no. 2, pp. 31-35, 2013.
[14] K. K. Alaneme, “Influence of thermo-mechanical treatment on the tensile behaviour and CNT evaluated fracture toughness of borax premixed SiCp reinforced aluminum (6063) composites”, Int. J. of Mech. and Materials Eng., vol. 7, pp. 96-100, 2012.
[15] K.K Alaneme, “Fracture toughness (K1C) evaluation for dual phase low alloy steels using circumferential notched tensile (CNT) specimens, Materials Research., vol. 14, no. 2, pp. 155‐160, 2011.
[16] G. E. Dieter, Mechanical metallurgy. Singapore: McGraw‐Hill, 1988.
[17] S. K. Nath and U. K. Das, “Effect of microstructure and notches on the fracture toughness of medium carbon steel”, J. of Naval Architecture and Marine Eng., vol. 3, pp. 15‐22, 2006.
[18] T. Chen, C. Yuan, M. Fu, Y. Ma, Y. Li, and Y. Hao”, Friction and wear properties of casting in-situ silicon particle reinforced ZA27 composites”, China Foundry, vol. 6, no. 1, 1-8, 2009.
[19] T. W. Courtney, Mechanical behaviour of materials, 2nd ed. India: Overseas Press, 2006.
[20] K. K. Alaneme, S.M. Hong, I. Sen, E. Fleury, U. Ramamurty, “Effect of copper addition on the fracture and fatigue crack growth Behaviour of solution heat‐treated SUS 304H austenitic steel”, Materials Sci. and Eng.: A, vol. 527, no. 18‐19, pp. 4600 – 4604, 2010.