• 제목/요약/키워드: novel materials

검색결과 1,879건 처리시간 0.032초

L-PBF 공정으로 제조된 Nd-Fe-B계 영구자석의 기판 가열에 따른 미세조직과 자기적 특성 변화 (Effect of Substrate Pre-heating on Microstructure and Magnetic Properties of Nd-Fe-B Permanent Magnet Manufactured by L-PBF)

  • 김연우;박하음;김태훈;김경태;유지훈;최윤석;박정민
    • 한국분말재료학회지
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    • 제30권2호
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    • pp.116-122
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    • 2023
  • Because magnets fabricated using Nd-Fe-B exhibit excellent magnetic properties, this novel material is used in various high-tech industries. However, because of the brittleness and low formability of Nd-Fe-B magnets, the design freedom of shapes for improving the performance is limited based on conventional tooling and postprocessing. Laser-powder bed fusion (L-PBF), the most famous additive manufacturing (AM) technique, has recently emerged as a novel process for producing geometrically complex shapes of Nd-Fe-B parts owing to its high precision and good spatial resolution. However, because of the repeated thermal shock applied to the materials during L-PBF, it is difficult to fabricate a dense Nd-Fe-B magnet. In this study, a high-density (>96%) Nd-Fe-B magnet is successfully fabricated by minimizing the thermal residual stress caused by substrate heating during L-PBF.

Multicomponent Nanostructured Materials for Separation Membranes

  • Peinemann, Klaus-Viktor
    • 한국막학회:학술대회논문집
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    • 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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    • pp.11-11
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    • 2004
  • Under the coordination of GKSS a new European project in the field of membrane development started recently. This project focuses on the development of novel nanostructured materials for selective material transport and separation. Two classes of materials will be developed in this project: nanostructured organic/inorganic hybrid materials and functional self-organized supramolecular copolymers.(omitted)

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Enhanced Electrical Performance of SiZnSnO Thin Film Transistor with Thin Metal Layer

  • Lee, Sang Yeol
    • Transactions on Electrical and Electronic Materials
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    • 제18권3호
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    • pp.141-143
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    • 2017
  • Novel structured thin film transistors (TFTs) of amorphous silicon zinc tin oxide (a-SZTO) were designed and fabricated with a thin metal layer between the source and drain electrodes. A SZTO channel was annealed at $500^{\circ}C$. A Ti/Au electrode was used on the SZTO channel. Metals are deposited between the source and drain in this novel structured TFTs. The mobility of the was improved from $14.77cm^2/Vs$ to $35.59cm^2/Vs$ simply by adopting the novel structure without changing any other processing parameters, such as annealing condition, sputtering power or processing pressure. In addition, stability was improved under the positive bias thermal stress and negative bias thermal stress applied to the novel structured TFTs. Finally, this novel structured TFT was observed to be less affected by back-channel effect.

A Novel Technoque for Characterization of Membranes

  • Webber, Ronald;Jena, Akshaya;Gupta, Krishna
    • 한국막학회:학술대회논문집
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    • 한국막학회 2001년도 제14회 심포지엄 : 제2회 분리막 표준화(The 2nd Standardization of Membranes)
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    • pp.39-50
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    • 2001
  • The performance of membranes is governed their pore struture. Pore structures of porous materials can be determined by a number of techniques. However, The novel technique, capillary folw porometry has a number of advantages. In this technique, the sample is brought in contact with a liquid that fills the pores in the membrane spontaneously. Gas under pressure is used to force the liquid from the pores and increase gas flow. Gas flow rate measured as a function of gas pressure in wet and dry samples yield data on the largest pore size, the mean flow pore size, flow distribution and permeability. Pore characteristics of a number of membranes were measured using this technique. This technique did not require the use of any toxic material and the pressure employed was low. Capillary flow porometry is a suitable technique for measurement of the pore structure of many membranes.

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La2/3Ca1/3MnO3 Nanoparticles with Novel Magnetoresistance Property

  • Zhang, Jianwu;Jang, Eue-Soon;Chung, Il-Won;Choy, Jin-Ho
    • Bulletin of the Korean Chemical Society
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    • 제25권2호
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    • pp.182-184
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    • 2004
  • Fine $La_{2/3}Ca_{1/3}MnO_3$ nanocrystalline powders have been successfully prepared by modified citrate pyrolysis process. The obtained LCMO nanoscale grains have a mean particle size of about 30 nm under optimal treatment conditions. The particle size can be controlled by adjusting processing parameters, such as treatment temperature and calcination time. X-ray diffraction, SEM and magnetoresistance effect were employed to study the crystal structure, morphology and magnetic property of these nanosized powders. A novel MR effect (MR > 45% (0 K < T < 340 K)) at room temperature has been found.

Novel transport materials for high-performance fluorescent and phosphorescent OLEDs

  • Bohm, E.;Anemian, R.;Busing, A.;Fortte, R.;Heil, H.;Kaiser, J.;Krober, J.;Leu, S.;Mujica-Fernaud, T.;Parham, A.;Pflumm, C.;Voges, F.
    • Journal of Information Display
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    • 제12권3호
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    • pp.141-144
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    • 2011
  • To improve the performance of blue fluorescent and green phosphorescent organic light-emitting diode devices, Merck developed novel green phosphorescent host and electron-transporting materials. The newly developed electron-transporting material improves the external quantum efficiency of blue fluorescent devices up to 8.7%, with an excellent lifetime. In combination with the newly developed host materials, the efficiency of green phosphorescent devices can be improved by a factor of 1.7, and the lifetime by a factor of 7.

A novel solution for thick-walled cylinders made of functionally graded materials

  • Chen, Y.Z.
    • Smart Structures and Systems
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    • 제15권6호
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    • pp.1503-1520
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    • 2015
  • This paper provides a novel solution for thick-walled cylinders made of functionally graded materials (FGMs). In the formulation, the cylinder is divided into N layers. On the individual layer, the Young's modulus is assumed to be a constant. For an individual layer, two undetermined constants are involved in the elastic solution. Those undetermined coefficients can be evaluated from the continuation condition along interfaces of layers and the boundary conditions at the inner surface and outer surface of cylinder. Finally, the solution for thick-walled cylinders made of functionally graded materials is obtainable. This paper provides several numerical examples which are useful for engineer to design a cylinder made of FGMs.

Development of Novel Electrode Materials for Plasma Display Panel

  • Kim, Chul-Hong;Chae, So-Ra;Lee, Min-Hee;Jeong, Hyun-Mi;Kim, Beom-Kwon;Heo, Eun-Gi;Choe, Deok-Hyeon;Lee, Byung-Hak
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.1437-1440
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    • 2008
  • In this paper, we mainly deal with metallic electrode materials and patterning processing of plasma display panels. We focus on the recent development status, where low cost and high performance electrode materials such as Ag-based single-layered bus, low cost-in-use and anti-migration address electrodes are briefly introduced. The technological trends and further works on novel electrode materials and processing are also discussed.

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A Novel Phase Transition from a Vertical Alignment to Optically Compensated Splay

  • Kim, S.J.;Shin, S.S.;Kim, H.Y.;Hong, S.H.;Lim, Y.J.;Lee, S.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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    • pp.512-515
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    • 2003
  • We have studied a novel vertical alignment liquid crystal cell. At initial state of a cell with rubbed parallel on top and bottom substrates, the vertically aligned LCs are twisted by $180^{\circ}$. However, after a critical voltage is applied to the cell, the configuration of the LC changes to optically compensated splay form, where the mid-director lies parallel to the substrate and thus the LC has two hybrid alignments around center.

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