1992 Fiscal Year Final Research Report Summary
Study on the Improvement of Superconductor by CO_2 Laser Irradiation
| Project/Area Number |
03650112
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
機械工作
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| Research Institution | Himeji Institute of Technology |
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Principal Investigator |
HASEGAWA Motoyoshi Himeji Institute of Technology, Professor, 工学部, 教授 (80180868)
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| Co-Investigator(Kenkyū-buntansha) |
KONISHI Yasuo Himeji Institute of Technology, Research Associate, 工学部, 助手 (40215299)
KAKUNAI Satoshi Himeji Institute of Technology, Associate Professor, 工学部, 助教授 (10101130)
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| Project Period (FY) |
1991 – 1992
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| Keywords | Superconductor / Y-Ba-Cu-O / Bi-Sr-Ca-Cu-O / CO_2 Laser Irradiation / Critical Temperature / Critical Current Density |
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| Research Abstract |
Results that CO_2 laser irradiation was carried out to Y-Ba-Cu-O and Bi-Sr-Ca-Cu-O superconductors are summarized as follows.
1) Y-Ba-Cu-O superconductor
The critical temperature (Tc) of the reference sample which was sintered for eight hours is 90.1 K.
(1) Critical temperature was generally decreased as a sintering time of the superconductor was shortened. However, after only two minutes laser irradiation, 92 K of maximum critical temperature could be obtained from the material which was sintered for only one hour. This optimized irradiation condition was found out to be 40 W of laser power and 22 Hz of scanning frequency.
(2) In order to raise a critical current density, optimum irradiation condition was 60 W and 42 Hz of scanning frequency.
2) Bi-Sr-Ca-Cu-O superconductor
The following results were found out after two minutes laser irradiation to the reference sample (Tc=94.5 K) which was sintered for 50 hours.
(1) Critical temperature showed a similar tendency to the Y-Ba-Cu-O superconductor. 102.4 K of maximum critical temperature could be obtained in the condition of 20 W of laser power and 22 Hz of scanning frequency.
(2) Critical current density showed maximum value in the 80 W of laser power and 62 Hz of scanning frequency. Comparing the reference sample, the high improvement in physical properties was observed after only two minutes laser irradiation.
(3) It was confirmed that the volume percentage was improved from 69.9 % to 84.3 % in the condition of 80 W of laser power and 62 Hz of scanning frequency.
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