The Modification of β-Al₅FeSi Phase in Al-Si-Mg-Fe Alloys by Utilizing Recycled Beverage Can Body in Casting Process

Abstract:

The acicular iron intermetallic compound, β-Al₅FeSi, is often quoted as disadvantages in aluminum based alloy ingots because of its brittleness. This undeniable phase, however, is found to show less effects on the ingots properties if trace manganese is added. The modified round ended and Chinese script-like structure showed significant higher ductility. The present work reports results of prospective experiments designed for obtaining shape modification of the iron intermetallic compound exclusively from readily available scrap aluminum cans as a source of manganese. A356 aluminum alloy with 1 wt.% iron and 10 wt. % manganese calculated from recycled aluminum can was melted in a laboratory furnace. The molten metal was soaked at 800°C for different aging times ranging from 15, 60 to 120 minutes before undergoing the conventional casting process. The produced ingots were characterized concerning their microstructures, hardness and final composition, which allows estimating the proper aging time for the microstructure improvement. It was observed that the 60 minute-aging time yielded the best modification of 14 micron round ended needle morphology. However, the longer aging time resulted in lower hardness as the result of the obtained Al₁₅(MnFe)₃Si₂ as a majority phase.

• Periodical: Key Engineering Materials (Volumes 675-676)
• Pages: 660-663
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.675-676.660
• Online since: January 2016
• Authors: Sainatee Chakthin, Patarawan Kahawong, Payoon Senthongkaew
• Keywords: A356 Aluminium Alloy, Manganese Modification, Recycled Beverage can Body, β-Al₅FeSi

References

[1] J. Beddoes& J. Jibby, Principles of Metal Manufacturing Process, Canada Carleton University, (1999).

[2] A. Thirugnanamet, K. Sukumaran, U.T.S. Pillai, K. Raghukandan, B.C. Pai, Effect of Mg on the fracture Characteristics of cast Al-7Si-Mg alloys, Materials Science and Engineering. Vol. A445-446. (2007) 405-414.

DOI: 10.1016/j.msea.2006.09.063

[3] J. E Gluzleski, B.M. Closset, The Treatment of Liguid Aluminum-Silicon Alloys, American Foundrymen's Socity, USA., (1990).

[4] J.R. David, Aluminum and Aluminum Alloys, Materials Park USA., (1993).

[5] Z. Ma,A.M. Samuel, F.H. Samuel, H.W. Doty, S. Valtierra, A Study of Tensile Properties in Al-Si-Cu and A-Si-Mg Alloys: Effect of β Phase Intermetallics and Porosity, Materials Science and Engineering. A490 (2008) 36-51.

DOI: 10.1016/j.msea.2008.01.028

[6] L. Backerud, Solidification Characteristic of Aluminium Alloy, Strockholm Modern Casting, (1991).

[7] S.G. Shabestari, The Effect of iron and manganese on the formation of intermetallic compounds in aluminum-silicon alloys, Materials Science and Engineering. Vol. A383(2004) 289-298.

DOI: 10.1016/s0921-5093(04)00832-9

[8] S.S. Sreeja Kumari, R.M. Pillai, B.C. Pai, A Study on the Structure, Age Hardening and Mechanical Characteristics of Mn and Ca Added Al-7Si-0. 3Mg-0. 6Fe Alloys, Journal of Alloys Compounds. 453 (2008)167-173.

DOI: 10.1016/j.jallcom.2006.11.145