| Project/Area Number |
17560580
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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 | Hokkaido University |
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Principal Investigator |
MOHRI Tetsuo Hokkaido Univ., Grad.School of Eng., Prof., 大学院工学研究科, 教授 (20182157)
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| Project Period (FY) |
2005 – 2006
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| Project Status |
Completed (Fiscal Year 2006)
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| Budget Amount *help |
¥3,200,000 (Direct Cost: ¥3,200,000)
Fiscal Year 2006: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2005: ¥2,300,000 (Direct Cost: ¥2,300,000)
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| Keywords | Phase Diagram / Cluster Variation Method / Phase Field Method / Path Probability Method / Coarse graining / 自己触媒反応 / 時空粗視化 / スケーリング則 |
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| Research Abstract |
Time dependent phase diagram is a hypothetical phase diagram which posses a time axis in addition to an ordinary composition axis. Hence, in the infinite time limit, it emerges to an equilibrium phase diagram. In order to deal with time dependent phenomena which is the basis of the time dependent phase diagram, we employed two theoretical tools. One is the Cluster Variation Method (and Path Probability Method) and the other is the Phase Field Method. In addition to these two methods, electronic structure calculation is also attempted to perform first-principles calculations. The Phase Field Method consists of Cahn-Hilliard diffusion equation and Time dependent Ginzubrug Landau equation. In general, Phase filed Method is employed to deal with microstructure evolution process and not much attempt has been performed for atomistic calculations. While Cluster Variation Method is the atomistic theory and deal with the statistical mechanics on the discrete lattice. In order to describe the multiscale phenomena from atomistic to microstructural scale in a consistent manner, it is indispensable to introduce a proper coarse graining procedure. The renormalization group theory is a rigorous mathematical tool, however it is not an easy task to apply the theory to individual problems. The body of this project has been devoted to establish and introduce coarse graining procedure which is proper enough to provide a reasonable result and efficient enough to perform calculations within a reasonable time scale. The developed method enables us to attempt first principles calculation of time evolution process of Anti Phase Boundary associated with the disorder-L10 transition for Fe-Pd and Fe-Pt systems. The procedure is quite powerful, however the coarse graining of the time scale remains as the future subject. This will be settled by extending Path Probability Method, and preliminary calculations are already attempted.
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