| Project/Area Number |
08405044
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| Research Category |
Grant-in-Aid for Scientific Research (A)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Inorganic materials/Physical properties
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| Research Institution | TOKYO INSTITUTE OF TECHNOLOGY |
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Principal Investigator |
KONDO Ken-ichi Tokyo Institute of Technology, Materials and Structures Laboratory, Professor, 応用セラミックス研究所, 教授 (50111670)
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| Co-Investigator(Kenkyū-buntansha) |
HIRAI Hisako Tokyo Institute of Technology, Materials and Structures Laboratory, Research Aso (60218758)
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| Project Period (FY) |
1996 – 1998
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| Project Status |
Completed (Fiscal Year 1998)
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| Budget Amount *help |
¥31,800,000 (Direct Cost: ¥31,800,000)
Fiscal Year 1998: ¥5,000,000 (Direct Cost: ¥5,000,000)
Fiscal Year 1997: ¥9,100,000 (Direct Cost: ¥9,100,000)
Fiscal Year 1996: ¥17,700,000 (Direct Cost: ¥17,700,000)
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| Keywords | laser-shock compression / carbon new phase / fullerene / shock wave / Amorphous diamond / nanocrystalline diamond / infrared radiometer / shock temperature / レーザー衝撃 / 高強度レーザー / 超高速 / 衝撃圧縮 / 超高圧力 / 超高温 / 炭素 / 新相 / レーザー衝撃圧力 |
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| Research Abstract |
Metastable phases of diamond, amorphous and nanocrystalline diamond, were produced by SCARQ (shock compression and rapid quenching) method based on the shock-gun technology, This method was also applied to a laser-shock technology, which was developed in this study. Two-types of laser-shock method were investigated ; one was the direct use of laser-induced ablation pressures, and the other was the use of the laser-driven flyer impact, For the latter, thin aluminum foils were accelerated by a high power Nd : YAG pulse laser and impacted PMMA window placed at a certain distance. Arrival time of the flyers was detected by a streak camera. Spatial changes in the arrival time revealed the curved flyer shape depending on the laser energy distribution which resulted in velocity distribution. Moreover, these profiles were strongly dependent on the distance from focal point of laser. Therefore, it was difficult to reduce the focal spot size less than 0.1 mm whose value was required for achieving the diamond transition pressure of 50 GPa. These experimental data were described by computer simulation based on one-dimensional hydro-code.
The structural change of fullerene films subjected to laser-shock compression using the laser was investigated by Raman scattering. Some samples transformed into fullerene polymer, and the photo-induced structural change of fullerene was also investigated.
An infrared radiometer for the accurate measurement of shock temperature was developed in order to investigate shock-induced, dynamic reaction processes of materials. To determine the IR-radiometer, the shock temperature measurements of carbon tetrachloride were conducted below 10 GPa, and the results confirmed that the system was available to measure relatively moderate shock temperatures lower than 1000 K.However, the system might be available at higher temperature in the case of laser-shock because of the small shock-compressed area.
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