Abstract
The formation of shrinkage porosity in a wedge-shaped A356 aluminum casting is observed in real-time using video radiography. From this observation, an image-processing technique is developed to quantify the through-thickness average porosity distribution in the casting as a function of time. The solidification and cooling of the casting are simulated in order to obtain the temperature and solid-fraction fields. It is found that once the wedge becomes isolated from the in-gate, surface sinks develop until the solid-fraction at the sinking location reaches approximately 45%. Subsequently, internal porosity starts forming in the upper part of the wedge. This interdendritic porosity spreads over the region with the lowest solid-fraction and continually increases until the casting is fully solidified. The maximum porosity percentage is measured in the thermal center of the wedge. A computational model is proposed to predict the evolution of the porosity in the aluminum casting.
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© 2016 TMS (The Minerals, Metals & Materials Society)
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Khalajzadeh, V., Goettsch, D.D., Beckermann, C. (2016). Real-Time Radiography and Modeling of Porosity Formation in an A356 Aluminum Alloy Wedge Casting. In: Tiryakioǧlu, M., Jolly, M., Byczynski, G. (eds) Shape Casting: 6th International Symposium. Springer, Cham. https://doi.org/10.1007/978-3-319-48166-1_5
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DOI: https://doi.org/10.1007/978-3-319-48166-1_5
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-48622-2
Online ISBN: 978-3-319-48166-1
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