| Project/Area Number |
17560583
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Physical properties of metals
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| Research Institution | Toyota Physical & Chemical Research Institute |
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Principal Investigator |
MIZUTANI Uichiro Toyota Physical & Chemical Research Institute, fellow (00072679)
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| Co-Investigator(Kenkyū-buntansha) |
TAKEUCHI Tsunehiro Ecotopia Science Institute, エコトピア科学研究所, Associate professor (00293655)
SATO Hirokazu Aichi University of Education, Department of Education, Professor (20024094)
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| Project Period (FY) |
2005 – 2007
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| Project Status |
Completed (Fiscal Year 2007)
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| Budget Amount *help |
¥3,710,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥210,000)
Fiscal Year 2007: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
Fiscal Year 2006: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 2005: ¥1,500,000 (Direct Cost: ¥1,500,000)
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| Keywords | structurally complex alloy phases / Hume-Rothery electron concentration rule / gamma-brasses / first-principles band calculations / phase stability mechanism / Hume-Rotyher電子濃度則 / 第一原理のband計算 / 第一原理のバンド計算 |
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| Research Abstract |
We have chosen Cu_5Zns and CuPAI_4 gamma-brasses containing 52 atoms in the unit cell as systems with relatively small number of atoms among structurally complex metallic alloy phases and clarified why they are stabilized at a particular electron concentration e/a=21/13 by performing the first-principles FLAPW band calculations. The present project has been conducted to extend the pioneering work above to gamma-brasses characterized by their own unique electronic structures.
1. In the first year of 2005, we have synthesized the TM-Zn (TM=Ni, Pd, Co and Fe) gamma-brasses and made their detailed structure analysis by using the powder diffraction apparatus in the beamline BLO2B2, SPring-8 synchrotron radiation facility, Japan. The stability mechanism of these gamma-brasses was studied by performing the FLAPW band calculations.
2. In the second year of 2006, we have synthesized the A1_8V_5 gamma-brass and made its detailed structure analysis by using the powder diffraction apparatus in the beamline BLO2B2, SPring-8 synchrotron radiation facility, Japan. The stability mechanism of the A1_8V_5 gamma-brass was studied by performing the FLAPW band calculations.
3. In the final year of 2007, we have synthesized the Ag_5Li_8 gamma-brass and made its detailed structure analysis by using the powder diffraction apparatus in the beamline BLO2B2, SPring-8 synchrotron radiation facility, Japan. The stability mechanism of the Ag_5Li_8 gamma-brass was studied by performing the FLAPW band calculations.
In conclusions, we revealed that the stabilization mechanism is not uniquely specified but is strongly system dependent, even though all. gamma-brasses studied are completely isostructural to each other. The present work clarified, for the first time, the presence of the limit to the applicability of the Hume-Rothery electron concentration rule for structurally complex alloy phases.
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