Synthesis of metal silicides using alkali metals and their thermoelectrical properties
Project/Area Number |
20685015
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Research Category |
Grant-in-Aid for Young Scientists (A)
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Allocation Type | Single-year Grants |
Research Field |
Inorganic industrial materials
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Research Institution | Tohoku University |
Principal Investigator |
YAMADA Takahiro Tohoku University, 多元物質科学研究所, 准教授 (10358260)
|
Project Period (FY) |
2008 – 2010
|
Project Status |
Completed (Fiscal Year 2010)
|
Budget Amount *help |
¥24,830,000 (Direct Cost: ¥19,100,000、Indirect Cost: ¥5,730,000)
Fiscal Year 2010: ¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000)
Fiscal Year 2009: ¥2,990,000 (Direct Cost: ¥2,300,000、Indirect Cost: ¥690,000)
Fiscal Year 2008: ¥19,240,000 (Direct Cost: ¥14,800,000、Indirect Cost: ¥4,440,000)
|
Keywords | 無機合成 / 材料合成プロセス / 熱電変換材料 / 金属シリサイド / 金属ケイ化物 / ナトリウム / 低温合成 / 高温構造材料 / 準安定相 / 耐酸化被膜 / 鉄シリサイド / 低温焼結 / 熱電材料 |
Research Abstract |
Powder and bulk of thermoelectric metal silicides such as β-FeSi_2,MnSi_<1.7+δ>, CoSi, CrSi_2,and Mg_2Si were prepared by heating mixtures of Si and metal powders or Si powders and compact body of metal powders with Na at low temperatures (500-900℃). Thermoelectric properties of the prepared metal silicides were characterized. The existence of Na-Si melt above ca. 500℃ was revealed by the study of Na-Si phase diagram. It indicates that the metal silicides are prepared by a reaction of Si (liquid) in the melt with the metals (solid). Powder of high-melting point metal silicides such as α-MoSi_2and NbSi_2,and metastable phase β-MoSi_2were prepared at 800,627,and 600-C, respectively. NbSi_2layer, which has oxidation resistance, was fabricated on the surface of Nb plate by heating the Nb plate with Si powder and Na. It was demonstrated that the new preparation method using Na can be adopted for the low-temperature preparation of metal silicides.
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Report
(4 results)
Research Products
(95 results)