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Rheocasting-Melt Treatment

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Semi-Solid Processing of Aluminum Alloys

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Abstract

The process of melt treatment (grain refining and modification) is a routine practice for conventional Al–Si alloys casting. For SSM processes, it is worthwhile to see the effect of grain refiner and modification on the primary α-Al dendrites and eutectic silicon. This chapter provides a detailed analysis to verify the effect of melt treatment on the microstructure of as-cast SSM billets. The mechanism of grain refining and modification is examined through thermal analysis, rheological studies, and quantitative metallographic characterization for a range of grain refining master alloys and Sr-based modifiers in different rheocasting processes.

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Notes

  1. 1.

    FactSage is a commercial thermodynamic-based software package (http://www.crct.polymtl.ca/factsage)

  2. 2.

    An isopleth is a type of phase diagram which may come from ternary or higher degree system where the phase relationship is identified for the elements of interest at different temperatures with variation of one element.

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Authors and Affiliations

  1. University of Alberta, Edmonton, AB, Canada

    Shahrooz Nafisi

  2. The University of Adelaide, Adelaide, SA, Australia

    Reza Ghomashchi

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Nafisi, S., Ghomashchi, R. (2016). Rheocasting-Melt Treatment. In: Semi-Solid Processing of Aluminum Alloys. Springer, Cham. https://doi.org/10.1007/978-3-319-40335-9_6

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