• 제목/요약/키워드: Carbothermal reduction

검색결과 94건 처리시간 0.023초

C/Si 몰 비가 TEOS와 페놀수지를 출발원료 사용하여 합성된 β-SiC 분말의 특성에 미치는 영향 (Effect of the C/Si Molar Ratio on the Characteristics of β-SiC Powders Synthesized from TEOS and Phenol Resin)

  • 염미래;박상환;김영욱
    • 한국세라믹학회지
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    • 제50권1호
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    • pp.31-36
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    • 2013
  • ${\beta}$-SiC powders were synthesized by a carbothermal reduction process using $SiO_2$-C precursors fabricated by a sol-gel process using phenol resin and TEOS as starting materials for carbon and Si sources, respectively. The C/Si molar ratio was selected as an important parameter for synthesizing SiC powders using a sol-gel process, and the effects of the C/Si molar ratio (1.4-3.0) on the particle size, particle size distribution, and yield of the synthesized ${\beta}$-SiC powders were investigated. It was found that (1) the particle size of the synthesized ${\beta}$-SiC powders decreased with an increase in the C/Si molar ratio in the $SiO_2$-C hybrid precursors, (2) the particle size distribution widened with an increase in the C/Si molar ratio, and (3) the yield of the ${\beta}$-SiC powder production increased with an increase in the C/Si molar ratio.

생왕겨를 이용한 실리콘 카바이드 합성 (Synthesis of SiC Whiskers from Rice Hulls)

  • 길경선;김종학;고인용
    • 자원리싸이클링
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    • 제2권4호
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    • pp.17-22
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    • 1993
  • 왕겨와 활성탄을 출발물질로 하여 탄소열 환원법으로 SiC 휘스커를 합성하였다. 그리고, 이에 있어서 가수와 첨가제의 영향을 조사하였다. 실험온도는 $1450^{\circ}C$ 이었고 합성도니 SiC 휘스커는 후처리 후 SEM, XRD 분석을 행하였다. 반응관내에 수소의 농도가 높을수록, 총유량이 클수록 휘스커의 생성율이 증가하였으며 가스의 유속이 Ar : $H_2$=300:45(cc/min)이고 NaF : $CaF_2$= 1:1가 되도록 혼합하여, 첨가하고, Ni를 flake ($1{\times}1$mm)로 첨가한 경우에 가장 양호한 형태의 휘스커를 얻을 수 있었다.

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전기방사에 의한 섬유상 질화알루미늄 합성 및 특성 평가 (Synthesis and Characterization of Fiberous AlN by Electrospinning)

  • 전승엽;황진아;주제욱;전명표
    • 한국전기전자재료학회논문지
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    • 제30권7호
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    • pp.441-446
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    • 2017
  • Aluminum nitride fibers were synthesized by carbothermal reduction and nitridation of precursor fibers obtained by electrospinning. The starting materials used to synthesize the AlN fibers were $Al(NO_3)_3{\cdot}9H_2O$ and urea. Polyvinylpyrrolidone with increasing viscidity was used as the carbon source to obtain a composite solution. The mixed solution was drawn into a plastic syringe with a stainless steel needle, which was used as the spinneret and connected to a 20 kV power supply. A high voltage was supplied to the solution to facilitate the formation of a dense net of fibers on the collector. The precursor fibers were dried at $100^{\circ}C$ and then heated to $1,400^{\circ}C$ for 1 h in a microwave furnace under $N_2$ gas flow for the carbothermal reduction and nitridation. X-ray diffraction studies indicated that the synthesized fibers consisted of the AlN phase. Field emission scanning electron microscopy studies indicated that the diameter of the calcined fibers was approximately 100 nm.