Project/Area Number |
11555161
|
Research Category |
Grant-in-Aid for Scientific Research (B)
|
Allocation Type | Single-year Grants |
Section | 展開研究 |
Research Field |
Physical properties of metals
|
Research Institution | KYOTO UNIVERSITY |
Principal Investigator |
NISHITANI Shigeto Kyoto Univ., Engineering, Assoc. Prof., 工学研究科, 助教授 (50192688)
|
Co-Investigator(Kenkyū-buntansha) |
MATSUMIYA Toru Nippon Steel Corp., Fellow, 先端技術研究所, 部長
AOKI Masato Gifu Univ., Engineering, Assoc. Prof., 工学部, 助教授 (70192854)
松宮 徹 新日本製鐵(株), 先端技術研究所, 部長
|
Project Period (FY) |
1999 – 2002
|
Project Status |
Completed (Fiscal Year 2002)
|
Budget Amount *help |
¥13,800,000 (Direct Cost: ¥13,800,000)
Fiscal Year 2002: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 2001: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 2000: ¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 1999: ¥9,700,000 (Direct Cost: ¥9,700,000)
|
Keywords | Phase diagram / Frenkel method / Vibrational entropy / bcc-hcp transition / モンテカルロシミュレーション / Quasi-Harmonic近似 / 統計モーメント法 / Ti / ボンドオーダーポテンシャル / 有限温度 / モンテカルロ法 / 自由エネルギー / Einstein結晶モデル / タイトバインディング / フルポテンシャルLMTO法 / 状態図計算 / 遷移金属合金 / タイトバインディング理論 / モーメント近似 |
Research Abstract |
For the purpose of reliable calculations on free energies on elemental p-T diagram and binary phase diagram, we checked the effects of 1. many body interactions of enthalpy changes, and 2. anharmonic vibrational entropies. 1. Many body interactions The enthalpy changes arised from the environment dependency of chemical bondings are predicted by bond order potentials based on Tight binding approximation. We developed parallel code and applied them to predict formation enthalpies of dilution limit alloys. 2. Anharmonic vibrational entropies Thermal expansion and allotropic phase transitions are controlled by anharmonic effects of vibration entropies, which is reliably estimated by Frenkel method in Monte Cargo simulations. We developed also paralled code and applied it on bcc-hcp transition in Ti. Based on these simulations we also developed new method of reliable prediction on free energy changes of precipitate nucelations. We opened some of these developed codes in public, and the others are in progress.
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