• 제목/요약/키워드: triso

검색결과 51건 처리시간 0.032초

화학증착법에 의하여 제조된 탄화규소 코팅층의 기계적 특성 (Mechanical Properties of Chemical Vapor Deposited SiC Coating Layer)

  • 이현근;김종호;김도경
    • 한국세라믹학회지
    • /
    • 제43권8호
    • /
    • pp.492-497
    • /
    • 2006
  • SiC coating has been introduced as protective layer in TRISO nuclear fuel particle of High Temperature Gas cooled Reactor (HTGR) due to excellent mechanical stability at high temperature. In order to inhibit the failure of the TRISO particles, it is important to evaluate the fracture strength of the SiC coating layer. ]n present work, thin silicon carbide coating was fabricated using chemical vapor deposition process with different microstructures and thicknesses. Processing condition and surface status of substrate.affect on the microstructure of SiC coating layer. Sphere indentation method on trilayer configuration was conducted to measure the fracture strength of the SiC film. The fracture strength of SiC film with different microstructure and thickness were characterized by trilayer strength measurement method nanoindentation technique was also used to characterize the elastic modulus and th ε hardness of the SiC film. Relationships between microstructure and mechanical properties of CVD SiC thin film were discussed.

피복입자핵연료에서 증착조건이 탄화규소층의 특성에 미치는 영향 (Effect of Deposition Parameters on the Property of Silicon Carbide Layer in Coated Particle Nuclear Fuels)

  • 김연구;김원주;여승환;조문성
    • 한국분말재료학회지
    • /
    • 제23권5호
    • /
    • pp.384-390
    • /
    • 2016
  • Tri-isotropic (TRISO) coatings on zirconia surrogate beads are deposited using a fluidized-bed vapor deposition (FB-CVD) method. The silicon carbide layer is particularly important among the coated layers because it acts as a miniature pressure vessel and a diffusion barrier to gaseous and metallic fission products in the TRISO-coated particles. In this study, we obtain a nearly stoichiometric composition in the SiC layer coated at $1400^{\circ}C$, $1500^{\circ}C$, and $1400^{\circ}C$ with 20 vol.% methyltrichlorosilane (MTS), However, the composition of the SiC layer coated at $1300-1350^{\circ}C$ shows a difference from the stoichiometric ratio (1:1). The density decreases remarkably with decreasing SiC deposition temperature because of the nanosized pores. The high density of the SiC layer (${\geq}3.19g/cm^2$) easily obtained at $1500^{\circ}C$ and $1400^{\circ}C$ with 20 vol.% MTS did not change at an annealing temperature of $1900^{\circ}C$, simulating the reactor operating temperature. The evaluation of the mechanical properties is limited because of the inaccurate values of hardness and Young's modulus measured by the nano-indentation method.