• Title/Summary/Keyword: 탄화규소 필터

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Pore Structure Modification and Characterization of Porous Alumina Filter with Chemical Vapor Infiltration (CVI) SiC Whisker (화학증착 탄화규소 휘스커에 의한 다공성 알루미나 필터의 기공구조 개질 및 특성 평가)

  • 박원순;최두진;김해두
    • Journal of the Korean Ceramic Society
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    • v.41 no.7
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    • pp.518-527
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    • 2004
  • In this study, SiC whiskers were grown in porous alumina substrate in order to enhance the filtering efficiency, performance, and durability by controlling pore morphology. This experiment was performed by Chemical Vapor Infiltration (CVI) in order to obtain the whiskers on the inside of pores as well as on the surface of porous the A1$_2$O$_3$ substrate. The deposition behavior was changed remarkably with the deposition position, temperature, and input gas ratio. First, the mean diameter of whisker was decreased as the position of observation moved into the inside of substrate due to the reactant gas depletion effect'. Second, the deposition temperature caused the changes of the deposition type such as debris, whiskers and films and the change in morphology affect the various properties. When SiC films were deposited. the gas permeability and the specific surface area decreased. However, the whisker showed the opposite result. The whiskers increase not only the specific surface area and minimizing pressure drop but also mechanical strength. Therefore it is expected that the porous alumina body which deposited the SiC whisker is the promising material for the filter trapping the particles.

Fabrication and Properties of SiC Candle Filter by Vacuum Extrusion and Ramming Process (II) (진공 압출성형 및 래밍성형 공정에 의한 탄화규소 캔들 필터 제조 및 특성 (II))

  • Han, In-Sub;Seo, Doo-Won;Kim, Se-Young;Hong, Ki-Seog;Woo, Sang-Kuk;Kim, Young-Wook
    • Journal of the Korean Ceramic Society
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    • v.47 no.6
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    • pp.515-523
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    • 2010
  • Porous SiC candle filter preforms were fabricated by extrusion and ramming process. To fabricate SiC candle filter preform, commercially available F180 mesh ($85\;{\mu}m$) $\alpha$-SiC powder and $44\;{\mu}m$ mullite, $CaCO_3$ powder were used as the starting materials. The candle type preforms were fabricated by vacuum extrusion and ramming process, and sintered at $1400^{\circ}C$ 2 h in air atmosphere. Corrosion test of the sintered candle filter specimens as forming method was performed at $600^{\circ}C$ for 2,400 h in simulated IGCC syngas atmosphere. The effect of forming method on mechanical properties, pore distribution, microstructure and crystalline phase was investigated.

Fabrication and Properties of the SiC Candle Filter by Vacuum Extrusion and Ramming Process (진공 압출성형 및 래밍성형 공정에 의한 탄화규소 캔들 필터 제조 및 특성)

  • Shin, Myung-Kwan;Han, In-Sub;Seo, Doo-Won;Kim, Se-Young;Woo, Sang-Kuk;Lee, Seoung-Won;Kim, Young-Wook
    • Journal of the Korean Ceramic Society
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    • v.46 no.6
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    • pp.662-667
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    • 2009
  • Porous SiC candle filter preforms were fabricated by extrusion and ramming process. To fabricate SiC candle filter preform, commercially available 85 ${\mu}m\;{\alpha}-$-SiC powder and 44 ${\mu}m$ mullite, CaC$O_3$ powder were used as the starting materials. The candle type preforms were fabricated by vacuum extrusion and ramming process, and sintered at $1400{^{\circ}C}$ 2 h in air atmosphere. The effect of forming method on porosity, density, strength (flexural and compressive strength) and microstructure was investigated. Also, corrosion test of the sintered candle filter specimens as forming method was performed at $600{^{\circ}C}$ in IGCC syngas atmosphere. The sintered SiC filter which was formed by ramming process has more higher density and exhibit higher strength than extruded filter. Its maximum density and 3-point bending strength were 2.00 g/$cm^3$ and 45 MPa, respectively.