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Icosahedral phase formation in rapidly quenched aluminum-ruthenium alloys

Published online by Cambridge University Press:  31 January 2011

Steven M. Anlage
Affiliation:
Applied Physics and Materials Science, California Institute of Technology, Pasadena, California 91125
Brent Fultz
Affiliation:
Applied Physics and Materials Science, California Institute of Technology, Pasadena, California 91125
Kannan M. Krishnan
Affiliation:
National Center for Electron Microscopy, Lawrence Berkeley Laboratory, Berkeley, California 94720
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Abstract

Systematic rapid quenching experiments on the icosahedral phase-forming system Al1 − xRux were performed for × < 20 at. %. The solidified alloys have been studied by electron microscopy and x-ray diffraction to determine their composition, constituent phases, and phase morphology. It has been determined that the icosahedral phase must form directly from the liquid and, at these quench rates, is always found in the presence of second or third phases. The results have been summarized in a metastable phase diagram appropriate for rapid solidification of Al1 − xRux at piston and anvil quench rates. This metastable phase diagram describes the results for Ru concentrations less than 14 at. %.

Type
Articles
Copyright
Copyright © Materials Research Society 1988

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References

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