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dc.contributor.advisorKaufman, Michael J.
dc.contributor.authorMarshall, Ryan
dc.date.accessioned2016-01-19T16:44:30Z
dc.date.accessioned2022-02-03T12:53:58Z
dc.date.available2016-01-19T16:44:30Z
dc.date.available2022-02-03T12:53:58Z
dc.date.issued2015
dc.identifierT 7945
dc.identifier.urihttps://hdl.handle.net/11124/170004
dc.description2015 Fall.
dc.descriptionIncludes illustrations (some color).
dc.descriptionIncludes bibliographical references.
dc.description.abstractSamples of an Al-Fe-V-Si alloy with and without small Y additions were prepared by copper wedge-mold casting. Analysis of the microstructures developed at intermediate cooling rates revealed the formation of an atypical morphology of the cubic α-Al12(Fe/V)3Si phase (Im3¯ space group with a = 1.26 nm) in the form of a microeutectic with α-Al that forms in relatively thick sections. This structure was determined to exhibit promising hardness and thermal stability when compared to the commercial rapidly solidified and processed Al-Fe-V-Si (RS8009) alloy. In addition, convergent beam electron diffraction (CBED) and selected area electron diffraction (SAD) were used to characterize a competing intermetallic phase, namely, a hexagonal phase identified as h-AlFeSi (P6/mmm space group with a = 2.45 nm c = 1.25 nm) with evidence of a structural relationship to the icosahedral quasicrystalline (QC) phase (it is a QC approximant) and a further relationship to the more desirable α-Al12(Fe/V)3Si phase, which is also a QC approximant. The analysis confirmed the findings of earlier studies in this system, which suggested the same structural relationships using different methods. As will be shown, both phases form across a range of cooling rates and appear to have good thermal stabilities. Additions of Y to the alloy were also studied and found to cause the formation of primary YV2Al20 particles on the order of 1 μm in diameter distributed throughout the microstructure, which otherwise appeared essentially identical to that of the Y-free 8009 alloy. The implications of these results on the possible development of these structures will be discussed in some detail.
dc.format.mediumborn digital
dc.format.mediummasters theses
dc.languageEnglish
dc.language.isoeng
dc.publisherColorado School of Mines. Arthur Lakes Library
dc.relation.ispartof2015 - Mines Theses & Dissertations
dc.rightsCopyright of the original work is retained by the author.
dc.subjectaluminum
dc.subjectapproximant
dc.subjectchill cast
dc.subjecthigh temperature
dc.subjectquasicrystal
dc.subjectRS8009
dc.titleCharacterization of novel microstructures in Al-Fe-V-Si and Al-Fe-V-Si-Y alloys processed at intermediate cooling rates
dc.typeText
dc.contributor.committeememberMidson, Stephen
dc.contributor.committeememberField, Robert
thesis.degree.nameMaster of Science (M.S.)
thesis.degree.levelMasters
thesis.degree.disciplineMetallurgical and Materials Engineering
thesis.degree.grantorColorado School of Mines


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