• 한국초전도학회:학술대회논문집
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• 2009.07a
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• pp.13-13
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• 2009

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.189-192
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• 2000

High-temperature superconductor of Bi-2212 system was fabricated by CFP(centrifugal forming process). To make a uniform specimen slurry was prepared in the ratio of 7:3(powder:binder) and ball milled for 24 hours. Milled slurry was charged into a rotating mold with 450 rpm and dried at room temperature. Then the specimen was performed binder burn-out at 35$0^{\circ}C$ and heated for partial melting to 86$0^{\circ}C$. XRD analysis of most specimens were shown 2212 phase and observed a local plate shaped microstructure with a well aligned c-axis direction from SEM images. T$_{c}$(Critical temperature) of Bi-2212 was 64K.K.

• Electrical & Electronic Materials
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• v.7 no.4
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• pp.306-311
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• 1994

In this study, the influence of the powder sintering, the 2nd sinteiing and the grinding time on the Superconducting properties in the Bi(Pb)SiCaCuO Superconductor has been studied. From the analysis of SEM and XRD patterns, it was known that the sample prepared by the process of powder sintering has a porous microstructure with the critical temperature(Tc) below 77K, while the sample prepared by the 2nd sintering has a highly oriented microstructure with the Tc above 100K. The Critical Current Density(Jc) of the sample prepared by the 2nd sintering was better than the sample prepared by the process of powder sinteiing, but it's Jc, was low in practical use. Also, the effect of grinding time from 0[min] to 120[min] was investigated. As the grinding time is increased, the samples degraded from high-Tc phase to low-Tc phase and nonsuperconducting phases.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1988.10a
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• pp.98-101
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• 1988

The material system (Bi$\sub$0.7/Pb$\sub$0.3/)Sr$_1$Ca$_1$Cu$\sub$1.8/Ox forms, at 845$^{\circ}C$, two major phases having a high Tc(100K) and a low Tc(∼70K) both of which consists of platelets and a non-superconducting minor phase which has rod-like shape and isolated by the major phases. As the sintering period increases, the amount of high Tc phase increases accompanying the decrease in low Tc phase while the amount of the non-superconducting phase is sintering period independent, resulting in a superconductor with Tc of 100K. Changes in compositions of each phase also occur during sintering due to evaporation of bismuth and lead.

• Journal of the Korean Ceramic Society
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• v.24 no.6
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• pp.602-604
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• 1987

The high TcY1Ba2Cu3Ox superconductor has recently gained widespread interest in the scientific community. The principal problems at the present time are how to densify this material and how to raise the critical current density. To date the majority of samples have had densities of 90%(of theoretical) or less. In this study we report that we obtained density of 96% by Hot-Pressing method.

• Progress in Superconductivity
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• v.2 no.1
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• pp.11-14
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• 2000

The notion of the finite pairing interaction energy range Td is shown to result in a linear temperature dependence of the London magnetic penetration depth length, ${\Delta}{\lambda}{/\lambda}(0)=(T/Td)2/\pi)ln2$ at low T in the case of the s-wave pairing state, accounting for data of high Tc superconductor by Hardy et al.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1238-1239
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• 2008

The high Tc supeconductor of ceramic oxides type was studied for finding its application field. The results reportaed in this paper on the stability of the ceramic superconductors and the resistance to ripening in the BCO liquid phase at elevated temperature opens a processing window for engineering the microstructure of large superconductor at the nanoscale level. The results suggest further that the introduction of highly efficient artifical pinning center to bulk ceramics superconductor.

• 한국초전도학회:학술대회논문집
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• 2009.07a
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• pp.106-106
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• 2009

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.4
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• pp.209-212
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• 2006

The electromagnetic effect observed in a BiSrCaCuO superconductor was studied. The electromagnetic properties of a $Ag_2O$ doped BiSrCaCuO superconductor and an undoped superconductor were evaluated to investigate the contribution of the pinning effect. It was confirmed experimentally that a large amount of magnetic flux was trapped in the $Ag_2O$ doped BiSrCaCuO than that in the undoped one, indicating that the pinning centers of magnetic flux are related closely to the occurrence mechanism of magnetic phenomena. It was considered that by adding $Ag_2O$, the area where normal conduction takes place increases and the magnetic flux penetrating through the sample increases. It also was considered that $Ag_2O$ acts to increase pinning centers of magnetic flux.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.8
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• pp.785-789
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• 2006

BiSrCaCuO(2223) superconductor was fabricated by the thermal pyrolysis method. The superconducting precursor produced by the dehydration of the gel at $120^{\circ}C$ for 12 h is not in the amorphous state as expected but in a crystalline state. In this paper, the establishment of fabrication condition was examined so as to improve the related properties to the practical use of BiSrCaCuO superconductor, and we reported the production of the BiSrCaCuO by the pyrolysis method.