Electronic Structure and Phase Stability of Glassy Alloys

Abstract:

The electronic structure and phase stability of the Zr-Ni-Al ternary glassy alloys, have been systematically investigated experimentally and theoretically. Thermal stability and crystallization process have been clarified by the DSC and XRD measurements. Composition dependence of the stability parameter; Tg/Tl has been clarified. The electronic structure around the Fermi level has been investigated by using the high resolution UPS. It is found that there is a sizable pseudogap at the Fermi level of the electronic structure of the Zr65Ni20Al15 glassy alloy. The DVXα calculations for the charateristic clusters in the Zr-Ni-Al glassy alloy having high glass forming ability have been also performed. It is found that these clusters formation reduces the internal energy and can contribute to the phase stability. The LMTO-ASA band calculations for the Zr6NiAl2 compound which is the most relevant compound to the Zr60Ni25Al15 glassy alloy have been also performed. It is found that there is a sizable pseudogap at the Fermi level in its electronic structure, suggesting exiting of the pseudogap of the glassy alloy.

• Periodical: Materials Science Forum (Volumes 539-543)
• Pages: 2048-2053
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.539-543.2048
• Online since: March 2007
• Authors: Masashi Hasegawa, Tsunehiro Takeuchi, Kazuo Soda, Hirokazu Sato, Uichiro Mizutani
• Keywords: Band Calculation, Cluster, DVXα, Glassy Alloys, Local Structure, Phase Stability, Thermal Stability, UPS, Zirconium-Based Alloy

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