Abstract

Sand-cast plates were used to determine the effect of iron and manganese concentrations on porosity levels in Al-9 pct Si-0.5 pct Mg alloys. Iron increased porosity levels. Manganese additions increased porosity levels in alloys with 0.1 pct Fe, but reduced porosity in alloys with 0.6 and 1 pct Fe. Thermal analysis and quenching were undertaken to determine the effect of iron and managanese on the solidification of the Al-Si eutectic. At high iron levels, the presence of large β-Al5FeSi was found to reduce the number of eutectic nucleation events and increase the eutectic grain size. The preferential formation of α-Al15Mn3Si2 upon addition of manganese reversed these effects. It is proposed that this interaction is due to β-Al5FeSi and the Al-Si eutectic having common nuclei. Porosity levels are proposed to be controlled by the eutectic grain size and the size of the iron-bearing intermetallic particles rather than the specific intermetallic phase that forms.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.