Project/Area Number |
25420780
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Material processing/Microstructural control engineering
|
Research Institution | Japan Aerospace EXploration Agency (2014-2015) Shibaura Institute of Technology (2013) |
Principal Investigator |
KURIBAYASHI KAZUHIKO 国立研究開発法人宇宙航空研究開発機構, 宇宙科学研究所, 名誉教授 (70092195)
|
Co-Investigator(Kenkyū-buntansha) |
OZAWA SHUMPEI 千葉工業大学, 工学部, 准教授 (80404937)
|
Project Period (FY) |
2013-04-01 – 2016-03-31
|
Project Status |
Completed (Fiscal Year 2015)
|
Budget Amount *help |
¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000)
Fiscal Year 2015: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
Fiscal Year 2014: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
Fiscal Year 2013: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
|
Keywords | 無容器凝固 / 過冷却 / 準安定相 / ペロブスカイト / 過冷却凝固 / マルチフェロイック物質 / トレランス因子 / 過冷凝固 / 無容器プロセス / ナノコンポジット |
Outline of Final Research Achievements |
When the melt of some materials supercools below the melting temperature, the melt may solidify to metastable phases. Applying this method to LnFeO3 (Ln: Lanthanide), we reported the forming of metastable hexagonal phase (h-LnFeO3). Furthermore, we predicted that the geometrical condition of constitutive ions for forming h-LnFeO3 are strongly related to the tolerance factor TF. Based on this idea, we performed the containerless solidification of LnFeO3 and observed that the metastable phase solidifies directly from undercooled melts in the range from LuFeO3 to EuFeO3. However ,in SmFeO3, the stable phase was only observed. In order to verify these experimental results, we consider the geometrical condition of the ionic radii of constitutive ion for forming hexagonal phase, and derived 0.87 as the critical value of TF. This result well agrees with the experimental result because the values of TF in EuFeO3 and SmFeO3 are 0.870 and 0.874, respectively.
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