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Type of Document	Dissertation
Author	Tenhover, M.
URN	etd-09182006-154115
Persistent URL	http://resolver.caltech.edu/CaltechETD:etd-09182006-154115
Title	Mossbauer effect studies in yttrium based metallic glasses
Degree	PhD
Option	Applied Physics
Advisory Committee	Advisor Name Title William Lewis Johnson Committee Chair Pol E. Duwez Committee Member
Keywords	none
Date of Defense	1981-04-29
Availability	restricted
Abstract The short range order of a variety of Yttrium-3d transition metal glasses has been investigated using Fe57 Mossbauer Effect (ME) spectroscopy. We found that the ME spectra of these glasses could best be described in terms of a model which assumes two kinds of sites for the 3d elements. The nature of the two sites is radically different depending on whether the transition metal is Mn, Fe, Co, and Ni or Cu and Zn. We attributed the difference in the structure of these glasses to the same factors which determine whether a C-15 crystalline compound is stable in equilibrium. The microscopic nature of ME spectroscopy provides an interesting comparison between the nature of the short range order in crystalline and amorphous alloys. The process of crystallization has also been studied for a few glasses, and was found to occur in two distinct steps associated with the formation of hcp Y and a C-15 compound. In the final section we use the results of this study to design a novel high field superconducting material.
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