| Project/Area Number |
05452286
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
Structural/Functional materials
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| Research Institution | Tokyo Institute of Technology |
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Principal Investigator |
SATO Tatsuo Tokyo Institute of Technology, Faculty of Engineering Associate Professor., 工学部, 助教授 (90126318)
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| Co-Investigator(Kenkyū-buntansha) |
TEZUKA Hiroyasu Tokyo Institute of Technology, Faculty of Engineering, Research Associate., 工学部, 助手 (40180070)
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| Project Period (FY) |
1993 – 1994
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| Project Status |
Completed (Fiscal Year 1994)
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| Budget Amount *help |
¥6,400,000 (Direct Cost: ¥6,400,000)
Fiscal Year 1994: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1993: ¥5,400,000 (Direct Cost: ¥5,400,000)
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| Keywords | Aluminum alloys / Magnesium alloys / Transition Elements / Rare earth elements / Age-hardening / Recrystallization / Carolimetry / X-ray diffraction / 分散相 / 比熱変化 / 高温X線回折 |
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| Research Abstract |
Aluminum alloys containing transition elements and rare earth elements such as Zr, Sc, Y,Er and Yb were produced using DC-cast and rapid solidification techniques. Al-Li alloys containing Ag, Au, Cu and Zn were also produced. Magnesium alloys containing Y,Nd and Sm were carefully fabricated. Precipitation microstructurs, deformed and recrystallized microstructures were observed and mechanical properties at high temperatures were evaluated.
In the alloys containing Sc fine Al_3Sc precipitates with the L1_3-type structure were formed at temperatures around 623K.These precipitates were found to be more effective to retardrecrystallization than Al_3Zr ones. Rapidly solidified Al-Er and Al-Yb alloys produced extremely fine compounds which are expected to be effective to improve alloy properties. The phase stability of the delta'phase in Al-Li alloys was increased with the additional elements of Ag, Au and Mg. The coarsening rate of the delta'particles was also greatly suppressed by the additions of Ag, Au and Mg.Mgalloys containing rare earth elements exhibited markedly increased age-hardening due to the precipitation of the metastable phases. The mechanical strength at high temperatures was higher than that of the conventional Mg alloys. This is explained by the suppressed cross-slip deformation in the Mg alloys containing Y,Nd and Sm.
To conclude Al and Mg alloys containing transition elements and rare earth elements produce well controlled microstructures and exhibit improved mechanical properties at high temperatures.
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