Project/Area Number |
02452233
|
Research Category |
Grant-in-Aid for General Scientific Research (B)
|
Allocation Type | Single-year Grants |
Research Field |
Physical properties of metals
|
Research Institution | Nagoya Institute of Technology |
Principal Investigator |
TANAKA Kazuhide Nagoya Institute of Technology, Prof, 工学部, 教授 (00024232)
|
Co-Investigator(Kenkyū-buntansha) |
YAMADA Masaaki Nagoya Institute of Technology,Assis, 工学部, 助手 (30024342)
YOSHINARI Osamu Nagoya Institute of Technology,Assoc, 工学部, 助教授 (10134040)
|
Project Period (FY) |
1990 – 1992
|
Project Status |
Completed (Fiscal Year 1992)
|
Budget Amount *help |
¥6,400,000 (Direct Cost: ¥6,400,000)
Fiscal Year 1992: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1991: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1990: ¥5,500,000 (Direct Cost: ¥5,500,000)
|
Keywords | Glassy alloys / Rare-earth metal / Transition metal / Hydrogen / Atomic structure / Electronic structure / Hydrogen-storage alloys / Surface properties / 原子的構造 / 希土類金属 / 表面酸化 / X線光電子分光 / X線構造解析 / 構造 |
Research Abstract |
It is well known that rare-earth (RE) -transition metal (TM)- simple metal (SM) systems readily form glassy alloys over wide composition ranges and are very reactive to hydrogen. In this research, atomic and electronic structures and surface states of La-Ni-Mg(Al) and Nd-Fe-B alloy glasses and their hydrides have been studied by means of X-ray diffraction, X-ray photoemission spectroscopy and thermal desorption spectrometry. In all these systems the glass structures consist of random packing of the metal atoms, where however RE-TM interaction is strengthened. Hydrogenation alters the random structures by forming strong RE-H chemical bonds, which break the RE-TM bonds and cause micro-clustering of metal atoms. This effect was observed by radial distribution analysis of atomic structure and photoemission core-level and valence-band spectra consistently. Hydrogen can be stored in these glasses by H/M=1.0-1.7 depending on the compositions. Their hydrogen absorption-desorption properties have been studied in detail. Specifically, La_5Ni_<40>Mg_<55> alloy glass is found to be profitable for use as a hydrogen storage material. These studies have been published in regular papers and are going to be presented at international symposiums.
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