• 제목/요약/키워드: silicon Carbide

검색결과 748건 처리시간 0.023초

분무건조 및 대기 플라즈마 용사에 의한 탄화규소 세라믹스용 내환경 코팅재의 제조 및 평가 (Fabrication and Characterization of Environmental Barrier Coatings by Spray Drying and Atmospheric Plasma Spraying for Protection of Silicon Carbide Ceramics)

  • 풍범걸;문흥수;곽찬원;박지연;이기성
    • 한국세라믹학회지
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    • 제51권5호
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    • pp.481-486
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    • 2014
  • Environmental barrier coatings (EBCs) are used to protect SiC-based ceramics or composites from oxidation and corrosion due to reaction with oxygen and water vapour at high temperatures above $1000^{\circ}C$. Mullite ceramics have been studied for environmental barrier coatings for Si-based ceramics. More recently, rare earth silicate ceramics have been identified as more water vapour-resistant materials than mullite for environmental barrier coatings. In this study, we fabricate mullite and yttrium silicate ceramics by an atmospheric plasma spray coating method using spherical granules fabricated by spray drying. As a result, EBCs with thicknesses in the range of $200-300{\mu}m$ are successfully fabricated without any macroscopic cracks or interfacial delamination. Phase and microstructure analysis are conducted, and the basic mechanical properties, such as hardness and indentation load-displacement curves are evaluated.

싸이클로헥센 증기 공정에 의한 산소량이 적은 실리콘카바이드 섬유의 개발 (Development of Polymer-derived Silicon Carbide Fiber with Low Oxygen Content Using a Cyclohexene Vapor Process)

  • 윤병일;최우철;김명주;김재성;김정일;강홍구
    • 한국군사과학기술학회지
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    • 제20권5호
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    • pp.620-632
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    • 2017
  • A chemical vapor curing method(CVC) was developed to cure polycarbosilane(PCS) fibers by using cyclohexene vapour as a non-oxygen active reactant, instead of air in oder to prepare the silicon carbide(SiC) fiber with low oxygen content. A cross-linked PCS fibers by cyclohexene vapor showed a completely different variation in IR spectra in comparison to the air-cured PCS fiber. CVC method resulted in less than 3 wt% in oxygen content. In this experiment conditions, The average tensile strength and modulus of SiC fiber obtained by CVC had 1995 MPa and 183 GPa respectively, which is higher than that of SiC fiber prepared by air-curing process.

Formation of a Carbon Interphase Layer on SiC Fibers Using Electrophoretic Deposition and Infiltration Methods

  • Fitriani, Pipit;Sharma, Amit Siddharth;Lee, Sungho;Yoon, Dang-Hyok
    • 한국세라믹학회지
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    • 제52권4호
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    • pp.284-289
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    • 2015
  • This study examined carbon layer coating on silicon carbide (SiC) fibers by utilizing solid-state and wet chemistry routes to confer toughness to the fiber-reinforced ceramic matrix composites, as an alternative to the conventional pyrolytic carbon (PyC) interphase layer. Electrophoretic deposition (EPD) of carbon black nanoparticles using both AC and DC current sources, and the vacuum infiltration of phenolic resin followed by pyrolysis were tested. Because of the use of a liquid phase, the vacuum infiltration resulted in more uniform and denser carbon coating than the EPD routes with solid carbon black particles. Thereafter, vacuum infiltration with controlled variation in phenolic resin concentration, as well as the iterations of infiltration steps, was improvised to produce a homogeneous carbon coating having a thickness of several hundred nanometers on the SiC fiber. Conclusively, it was demonstrated that the carbon coating on the SiC fiber could be achieved using a simpler method than the conventional chemical vapor deposition technique.