• 제목/요약/키워드: Zone melting

검색결과 157건 처리시간 0.036초

Zone-melting Process of NdBaCuO under Low Oxygen Pressure

  • Soh, Dea-Wha
    • Transactions on Electrical and Electronic Materials
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    • 제3권2호
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    • pp.24-27
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    • 2002
  • The NdBaCuO superconductor samples were zone-melted in low oxygen partial pressure (1%O$_2$+99%Ar). The zone-melting temperature was decreased about 12$0^{\circ}C$ film 1,06$0^{\circ}C$, the zone-melting temperature in air. Thus the loss of liquid phase (BaCuO$_2$ and CuO) was reduced during: the zone-melting process. The content of non-superconducting phase Nd422 in zone-melted NdBaCuO samples was clearly decreased and, therefore, the substitution of Nd for Ba was occurred. The superconductivity of zone-melted Nd$_{1+x}$Ba$_{2-x}$Cu$_3$O$_{y}$ prepared under low oxygen partial pressure was distinctively improved.d.d.d.

Preparation of Zone-melted NdBaCuO under Low Oxygen Pressure

  • Soh, Dea-Wha;Fan, Zhan-Guo;Gao, Wei-Ying;Jeon, Jong-Woo
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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    • pp.85-88
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    • 2001
  • The NdBaCuO superconductor samples were Zone-melted in low oxygen partial pressure (1% $O_{2}+ 99% Ar$ ). The Zone-melting temperature was decreased about $120^{\circ}C$ from $1060^{\circ}C$ the zone-melting temperature in air. Thus the loss of liquid phase ($BaCuO_{2}$ and CuO) was reduced during the zone-melting process. The content of non-superconducting phase Nd422 in zone-melted NdBaCuO samples was clearly decreased, so was the substitution of Nd for Ba. The superconductivity of zone-melted $Nd_{1+x}Ba_{2-x}Cu_{3}O_{y}$ prepared under low oxygen partial pressure was distinctively improved.

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Preparation of Zone-melted NdBaCuO under Low Oxygen Pressure

  • wha, Soh-Dea;guo, Fan-Zhan;ying, Gao-Wei;Jeon Yongwoo
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집
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    • pp.85-88
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    • 2001
  • The NdBaCuO superconductor samples were Zone-melted in low oxygen partial pressure (1% O$_2$+99% Ar). The Zone-melting temperature was decreased about 120$^{\circ}C$ from 1060$^{\circ}C$ the zone-melting temperature in air. Thus the loss of liquid phase (BaCuO$_2$ and CuO) was reduced during the zone-melting process. The content of non-superconducting phase Nd422 in zone-melted NdBaCuO samples was clearly decreased, so was the substitution of Nd for Ba. The superconductivity of zone-melted Nd$\sub$1+x/Ba$\sub$2-x/Cu$_3$O$\sub$y/ prepared under low oxygen partial pressure was distinctively improved.

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Zone-melting Process of NdBaCuO Superconductor under Low Oxygen Pressure

  • Soh, Deawha;Zhanguo, Fan;Yingmei, Li
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2004년도 SMICS 2004 International Symposium on Maritime and Communication Sciences
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    • pp.6-8
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    • 2004
  • The NdBaCuO superconductor samples were zone-melted in low oxygen partial pressure (1 % $O_2$+99%Ar). The zone-melting temperature was decreased about 12$0^{\circ}C$ from 1, 06$0^{\circ}C$, the zone-melting temperature in air. Thus the loss of liquid phase (BaCu $O_2$and CuO) was reduced during the zone-melting process. The content of non-superconducting phase Nd422 in zone-melted NdBaCuO samples was clearly decreased and, therefore, the substitution of Nd for Ba was occurred. The superconductivity of zone-melted N $d_{1+x}$B $a_{2-x}$C $u_3$ $O_{y}$prepared under low oxygen partial pressure was distinctively improved.d.d.d.

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플라즈마/연소 융합기술을 이용한 세라믹계 유리 분말 기중용해로 개발 (Development of glass melting furnace using both plasma and combustion)

  • 동상근;이은경;정우남
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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    • pp.203-205
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    • 2014
  • This paper is suggesting about glass melting technology, using both plasma and combustion heat source. The mixed flame was formed to flow pattern of turning by plasma and combustion in melting zone. The burning time was extremely extended for vitrification of raw materials in melting zone, as a result, meting time was significantly reduced. This system was designed to smaller size than existing glass melting facilities. We had achieved to 30% energy saving, due to reduce residence time of melted materials inside furnace.

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Microstructure and Hardness of Surface Melting Hardened Zone of Mold Steel, SM45C using Yb:YAG Disk Laser

  • Lee, Kwang-Hyeon;Choi, Seong-Won;Yoon, Tae-Jin;Kang, Chung-Yun
    • Journal of Welding and Joining
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    • 제34권1호
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    • pp.75-81
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    • 2016
  • This study applied laser surface melting process using CW(Continuous wave) Yb:YAG laser and cold-work die steel SM45C and investigated microstructure and hardness. Laser beam speed, power and beam interval are fixed at 70 mm/sec, 2.8 kW and $800{\mu}m$ respectively. Depth of Hardening layer(Melting zone) was a minimum of 0.8 mm and a maximum of 1.0 mm that exceeds the limit of minimum depth 0.5 mm applying trimming die. In all weld zone, macrostructure was dendrite structure. At the dendrite boundary, Mn, Al, S and O was segregated and MnS and Al oxide existed. However, this inclusion didn't observe in the heat-affected zone (HAZ). As a result of interpreting phase transformation of binary diagram, MnS crystallizes from liquid. Also, it estimated that Al oxide forms by reacting with oxygen in the atmosphere. The hardness of the melting zone was from 650 Hv to 660 Hv regardless of the location that higher 60 Hv than the hardness of the HAZ that had maximum 600 Hv. In comparison with the size of microstructure using electron backscatter diffraction(EBSD), the size of microstructure in the melting zone was smaller than HAZ. Because it estimated that cooling rate of laser surface melting process is faster than water quenching.

제설기반 취약지역 보행자의 전기안전발판(융설용) 최적설계에 관한 연구 (A Study on an Optimal Design of Electric Snow Melting Mat for Vulnerable Walk Zone)

  • 권진욱;장철;황명환
    • 한국안전학회지
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    • 제31권6호
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    • pp.12-18
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    • 2016
  • This paper describes an optimal design of electric snow melting mat on vulnerable walk zone. In order to design an optimal electric power of snow melting mat and protect pedestrians with a nonslip mat, with considering protection of environmental pollution from abusing of the de-icing salts added calcium chloride. We analyzed nine snow melting mats through verification experiment in the condition of $-5^{\circ}C$, depending on three different kinds of heating material, electric heating cable, carbon heating film and carbon textile film. As a consequence, the $150W/m^2$ carbon textile film mat for snow melting was identified as an optimal power input and functional performance for pedestrians' safety on vulnerable walk zone. It is expected that the $150W/m^2$ carbon textile film mat would be useful to reduce slip down accidents by human error.

구역용융법으로 제작된 NdBaCuO 초전도체의 산소흡착 특성 (Oxygenation of Zone-melting NbBaCuO superconductor)

  • Soh, Dea-Wha;Fan, Zhanguo;Kim, Hee-Nam;Li, Xinyu;Gao, Weiying;Kim, Tae-Wan
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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    • pp.292-295
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    • 2001
  • The NdBaCuO superconducting samples were prepared by the Zone melting under low oxygen partial pressure. After the zone-melting the oxygenation process of the NdBaCuO samples in a oxygen flow furnace was studied. In order to compare the oxygenation condition the sintering NdBaCuO samples were studied also. In the study it is found that the optimum temperature for the oxygenation is $350^{\circ}C$, and the oxygen flow speed, the sample volume and the surface area of the sample would influence the oxygenation and the oxygen content.

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구역용융법으로 제작된 NdBaCuG 초전도체의 산소흡착 특성 (Oxygenation of Zone-melting NdBaCuG Superconductor)

  • Soh, Dea-Wha;Fan, Zhanguo;Kim, Hee-Nam;Li, Xinyu;Gao, Weiying;Kim, Tae-Wan
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집
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    • pp.292-295
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    • 2001
  • The NdBaCuO superconducting samples were prepared by the Zone melting under low oxygen partial pressure. After the zone-melting the oxygenation process of the NdBaCuO samples in a oxygen flow furnace was studied. In order to compare the oxygenation condition the sintering NdBaCuO samples were studied also. In the study it is found that the optimum temperature for the oxygenation is $350{\circ}C$, and the oxygen flow speed, the sample volume and the surface area of the sample would if1uence the oxygenation and the oxygen content.

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Zone-melting of EPD $YBa_2Cu_3O_x$ Thick Film under Low Oxygen Partial Pressure

  • 소대화
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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    • pp.263-266
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    • 2003
  • The fine $YBa_2Cu_3O_x$ powder ($0.2{\sim}1.0\;{\mu}m$) is produced by sol-gel method, and electrophoresis deposition is used for the preparation of $YBa_2Cu_3O_x$ thick films which are deposited on Ag wire. The oriented $YBa_2Cu_3O_x$ was tried to be prepared by the zone-melting method under low oxygen partial pressure. The orientation and the phase composition were examined by the X-ray diffraction and the superconductivities were measured by 4 line method. The critical current densities are still quite low, which may be due to unsuitable technical parameters for zone-melting of $YBa_2Cu_3O_x$ thick films. Therefore the heat treatment condition and controlling of low oxygen partial pressure should be improved in the future experiment.

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