• 한국초전도ㆍ저온공학회논문지
• /
• 제5권3호
• /
• pp.20-22
• /
• 2003

Y$_2$O$_3$ films were pulsed laser deposited on cube textured Ni and Ni-W substrates to be used as a single buffer layer of YBCO coated conductor. Initial deposition of $Y_2$O$_3$ films was performed in a reducing atmosphere, and subsequent deposition was done in the base pressure of the chamber and oxygen atmosphere. The $Y_2$O$_3$ films have a strong cube texture (The full width at half maximum of the ø-scan of $Y_2$O$_3$ was 8.4 which was the same as that of metal substrate) and smooth crack-free microstructure. The biaxially textured YBCO films (The full width at half maximum of the ø-scan was 10.2) pulsed laser deposited on the $Y_2$O$_3$/metal exhibited Tc(R=0) of 86.5K and Jc of 0.7 MA/cm2 at 77K in self field, representing that the $Y_2$O$_3$ single buffer layer is an efficient diffusion barrier of Ni and thus very promising for the achievement of high-Jc YBCO coated conductor.

• 한국분말재료학회지
• /
• 제25권2호
• /
• pp.165-169
• /
• 2018

Rare earth elements (REEs) are considered to be vital to modern industry due to their important roles in applications such as permanent magnets, automobile production, displays, and many more. The imbalance between demand and supply of REEs can be solved by recycling processes. Regarding the needs of industry and society, the International Organization for Standardization, Technical Committee 298 (ISO/TC298) Rare Earths has been recently launched for developing international standards on rare earth elements. In accordance with the suggestion of its constituents, it is tentatively working to develop the appropriate standards under five working groups (WG) on terms and definitions (WG1), element recycling (WG2), environmental stewardship (WG3), packaging, labelling, marking, transport, and storage (WG4), and testing analysis (WG5). The scope and structure of ISO/TC298 on the topic of rare earths is discussed in this document.

• 한국초전도학회:학술대회논문집
• /
• 한국초전도학회 2002년도 High Temperature Superconductivity Vol.XII
• /
• pp.81-81
• /
• 2002

• 한국초전도ㆍ저온공학회논문지
• /
• 제12권2호
• /
• pp.9-12
• /
• 2010

A lamination system using reflow soldering was developed to enhance the mechanical properties of high temperature superconductor (HTS) tape. The laminated coated conductor tape was fabricated using the continuous lamination process. The mean, maximum, and minimum tensile loads in a T-peel test of the laminated coated conductor were 9.9 N, 12.5 N, and 7.6 N, respectively. The critical current ($I_c$) distributions of the non-laminated and laminated coated conductor were compared using anon-contact Hall probe method. The transport $I_c$ nearly matched the non-contact $I_c$; however, some degraded Ic regions were found on the length of 800 cm of laminated coated conductor. We confirmed that the cause of the partially degraded $I_c$ was due to an increase in line tension by (1) solidification induced by a change of composition that usually occurs in molten brass (Cu, Zn) in solder, or (2) non-homogeneity of the thickness of the coated conductor or metal tapes. We suggest that reflow soldering is a promising method for reinforced HTS tape if the controlling solder thickness and lamination guide are modified.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2001년도 하계학술대회 논문집 C
• /
• pp.1718-1720
• /
• 2001

The route of surge arrester connection is very important because bends and kinds of leads increase the impedance to lightning surges and tend to nullify the effectiveness of a grounding electrode conductor. There is a need to know how effective installation of lightning surge arresters is made in order to control voltage and to absorb energy at high lightning currents. The effectiveness of a grounding conductor and bonding for 18[kV] metal oxide distribution line arresters was experimentally investigated with lightning and oscillating impulse voltages.

• Progress in Superconductivity
• /
• 제3권1호
• /
• pp.125-129
• /
• 2001

NiO buffer layers were deposited on texture Ni tapes fur YBCO coated conductors by MOCVD(metal organic chemical vapor deposition) method, using a single solution source. Variables were deposition temperature and flow rate of $0_2$carrier gas. At higher temperatures, The NiO(111) texture was well developed, but the NiO(200) texture was developed at low temperatures. The best result was obtained at the deposition temperature of$ 470^{\circ}C$ and the gas flow rate of 200 sccm. FWHM value of $\omega$-scan fur NiO(200) of the film and $\Phi$-scan for NiO(111) of the film was $4.2^{\circ}$ and $7^{\circ}$, respectively.

• 전기화학회지
• /
• 제21권2호
• /
• pp.21-27
• /
• 2018

본 총설에서는 최근 전세계적으로 각광 받고 있는 유기 금속 할라이드 페로브스카이트 소재에서 일어나는 이온 이동 현상에 대한 최신 연구에 대해 정리하였다. 페로브스카이트 물질 조성, 인가전압에 따라 다른 결과들이 보고되었지만, 실제 태양전지 작동 조건에서 iodide 가 이동하는 것으로 보이며, 때로는 methylammonium의 이동도 관찰된다. 페로브스카이트는 상온에서 전자와 이온이 동시에 이동하는 이른바 mixed conductor이고, 이는 페로브스카이트 태양전지 전류-전압곡선의 hysteresis, 장시간 작동에 따른 성능 저하 등에 지대한 영향을 미친다.

• 한국마이크로전자및패키징학회:학술대회논문집
• /
• 한국마이크로전자및패키징학회 2002년도 추계기술심포지움논문집
• /
• pp.159-163
• /
• 2002

최근 세라믹 칩 부품과 모듈등의 통신 부품에 관한 연구가 활발히 진행되고 있는 가운데 내장형 수동소자를 이용한 세라믹 3차원 모듈 개발에 관한 연구가 많은 연구 그룹에서 진행되고 있다. LTCC 시스템은 가격이 저렴하고 공정이 안정적이고 전기적 특성에서도 손실값이 작은점등의 많은 장점을 가지고 있다. 이러한 전기적 특성은 사용하는 재료의 물성에 직접적인 영향을 받게 된다. 사용 재료는 크게 도체와 유전체로 나뉘어질 수 있으며 특히 도체의 특성이 설계된 패턴에 의한 소자 특성에 큰 영향을 주게 된다. 본 연구에서는 금속 함량과 금속 입자 크기를 변화시킨 도체 페이스트를 직접 제작하고 스트립라인 레조네이터에 적용되었을 때의 6 ㎓ 까지의 고주파 특성을 비교 분석하였다.

• 공업화학
• /
• 제2권3호
• /
• pp.193-198
• /
• 1991

후막 구리도체는 귀금속계 도체에 비하여 가격이 저렴하고 전기전도도, 납땜성, 땜납 침식저항, 와이어 본딩성등의 양호한 성질 때문에 매우 중요성을 갖는다. 그러나 우수한 후막 구리도체를 형성하는 것은 구리가 높은 온도에서 쉽게 산화하는 성질로 인해 상당히 복잡하다. 양호한 구리후막을 얻기 위하여 하이브리드 마이크로회로업계는 질소분위기, 반응성분위기 또는 공기분위기를 사용한다. 이 글에서는 후막 구리도체의 소성공정과 세종류의 소성분위기에 대하여 종합적으로 고찰하였다.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2001년도 하계학술대회 논문집
• /
• pp.1076-1079
• /
• 2001

An anolmalous magnetoresistance effect has been theoretically studied at very low temperatures for composite normal metal conductors. This anomalous behavior is due to transverse Hall currents in the composite which would result in increased losses and higher effective resistance for the composite conductor. In this paper, transverse current flow and effective resistance with Cu-Al conductor configuration were analyzed using FEM(finite element method) for predicting the Hall losses to be resulted in anomalous magnetoresistance effect. And they are plotted three dimensionally to be visualized.