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F. Lasagni, A. Lasagni, C. Holzapfel, F. Mücklich, H.P. Degischer:
"Three Dimensional Study of Si-eutectic Structures in unreinforced and Short Fibre Reinforced Al-Alloys";
Talk: 12. Internationale Metallographie-Tagung, Leoben, Österreich; 09-27-2006 - 09-29-2006; in: "Fortschritte in der Metallographie. Sonderbände der Praktischen Metallographie", A. Kneissl (ed.); Werkstoff-Informationsgesellschaft mbH, Sonderbände der Praktischen Metallographie Band 38 (2006), ISBN: 3-88355-354-9; 177 - 183.

In this work, a detailed study of different eutectic architectures in unreinforced and reinforced AlSi(Sr) alloys is performed. In a previous work [1], the 3D morphology of deep etched Al-Si alloys was investigated, where an interconnected Si-network was observed in the as-cast condition for both unmodified and modified alloys. During solution treatment, Si spheroidizes changing its morphology from a lamellar (in case of the unmodified alloys) or a coral-fibrous structure (for the Sr modified-AlSi) into round Si particles, where the connectivity between the Si is disintegrated. The addition of Al2O3-short fibres has avoided the disintegration of the Si-network even after longer exposure times at 540°C. This was observed in deep-etched samples for which a 3D-Si/Al2O3 network was obtained after chemical dissolution of primary-Al.
A new Focused Ion Beam-Energy Dispersive Spectroscopy (FIB-EDX) method was implemented to study the 3D architecture of as cast and solution heat-treated Al-Si-alloys. These 3D structures can be reconstructed from sequential 2D sectioning and subsequent computer imaging. The obtained spatial resolution is higher than that achieved by synchrotron radiation computer tomography.

http://aleph.ub.tuwien.ac.at/F?base=tuw01&func=find-c&ccl_term=AC06587332