The Effect of Iron Content on Microstructure and Porosity of Secondary AlSi7Mg0.3 Cast Alloy

Authors

  • Denisa Závodská
    Affiliation

    Department of Materials Engineering, Faculty of Mechanical Engineering, University of Žilina, Univerzitná 8215/1, 010 26 Žilina, Slovak Republic

  • Eva Tillová
    Affiliation

    Department of Materials Engineering, Faculty of Mechanical Engineering, University of Žilina, Univerzitná 8215/1, 010 26 Žilina, Slovak Republic

  • Ivana Švecová
    Affiliation

    Department of Materials Engineering, Faculty of Mechanical Engineering, University of Žilina, Univerzitná 8215/1, 010 26 Žilina, Slovak Republic

  • Mária Chalupová
    Affiliation

    Department of Materials Engineering, Faculty of Mechanical Engineering, University of Žilina, Univerzitná 8215/1, 010 26 Žilina, Slovak Republic

  • Lenka Kuchariková
    Affiliation

    Department of Materials Engineering, Faculty of Mechanical Engineering, University of Žilina, Univerzitná 8215/1, 010 26 Žilina, Slovak Republic

  • Juraj Belan
    Affiliation

    Department of Materials Engineering, Faculty of Mechanical Engineering, University of Žilina, Univerzitná 8215/1, 010 26 Žilina, Slovak Republic

https://doi.org/10.3311/PPtr.12101

Abstract

In the present study, microstructure and porosity of AlSi7Mg0.3 cast alloy including various amounts (0.123; 0.454 and 0.655 wt. %) of iron were investigated. The alloys were produced as secondary (scrap-based - recycled). Iron leads to the formation of complex intermetallic phases during solidification, and how these phases can adversely affect mechanical properties, especially ductility, and also lead to the formation of excessive shrinkage porosity defects in castings. In order to determine the effect of iron addition to AlSi7Mg0.3 alloy, optical and SEM microscopy with EDX were used for microstructural examinations. Image analysis was conducted in order to determine effect of the Fe content on phases and porosity. It was found that increasing Fe content from 0.123 to 0.655 wt. % has no effect on SDAS but the morphology of Al-Si eutectic became finer. From EDX examinations, different Fe-based intermetallic phases (β-Al5FeSi and α-Al15(FeMg)3Si2) were observed. It was also observed that as Fe content increased, α-Al15(FeMg)3Si2 phases was transformed into Al5FeSi and the size and the number of Al5FeSi phases increases. The image analysis results revealed that porosity values were by increasing Fe content increased too. We can to predict, that with the increasing amount of Fe decreasing the mechanical properties (first of all) ductility (through long β-Al5FeSi intermetallic and high porosity).

Keywords:

Al-Si cast alloy, microstructure, porosity, effect of Fe

Published Online

2018-05-09

How to Cite

Závodská, D., Tillová, E., Švecová, I., Chalupová, M., Kuchariková, L., Belan, J. (2019) “The Effect of Iron Content on Microstructure and Porosity of Secondary AlSi7Mg0.3 Cast Alloy”, Periodica Polytechnica Transportation Engineering, 47(4), pp. 283–289. https://doi.org/10.3311/PPtr.12101

Issue

Section

Articles