• Title/Summary/Keyword: Zr coating

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Microstructure of ZrC Coatings of TRISO Coated Particles by Codeposition of Free Carbon and Control of Stoichiometry (유리탄소의 동시증착에 의한 TRISO 피복입자의 ZrC 코팅층 미세구조와 화학양론비 제어)

  • Ko, Myung-Jin;Kim, Daejong;Park, Ji Yeon;Cho, Moon Sung;Kim, Weon-Ju
    • Journal of the Korean Ceramic Society
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    • v.50 no.6
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    • pp.446-450
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    • 2013

  • TRISO coated particles with a ZrC barrier layer were fabricated by a fluidized-bed chemical vapor deposition (FBCVD) method for a use in a very high temperature gas-cooled reactor (VHTR). The ZrC layer was deposited by the reaction between $ZrCl_4$ and $CH_4$ gases at $1500^{\circ}C$ in an $Ar+H_2$ mixture gas. The amount of free carbon codeposited with in ZrC was changed by controlling the dilution gas ratio. Near-stoichiometric ZrC phase was also deposited when an impeller was employed to a $ZrCl_4$ vaporizer which effectively inhibited the agglomeration of $ZrCl_4$ powders during the deposition process. A near-stoichiometric ZrC coating layer had smooth surface while ZrC containing the free carbon had rough surface with tumulose structure. Surface roughness of ZrC increased further as the amount of free carbon increased.

  • https://doi.org/10.4191/kcers.2013.50.6.446 인용 PDF KSCI

Evaluation of antibacterial activity and osteoblast-like cell viability of TiN, ZrN and $(Ti_{1-x}Zr_x)N$ coating on titanium

  • Ji, Min-Kyung;Park, Sang-Won;Lee, Kwangmin;Kang, In-Chol;Yun, Kwi-Dug;Kim, Hyun-Seung;Lim, Hyun-Pil
    • The Journal of Advanced Prosthodontics
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    • v.7 no.2
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    • pp.166-171
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    • 2015

  • PURPOSE. The aim of this study was to evaluate antibacterial activity and osteoblast-like cell viability according to the ratio of titanium nitride and zirconium nitride coating on commercially pure titanium using an arc ion plating system. MATERIALS AND METHODS. Polished titanium surfaces were used as controls. Surface topography was observed by scanning electron microscopy, and surface roughness was measured using a two-dimensional contact stylus profilometer. Antibacterial activity was evaluated against Streptococcus mutans and Porphyromonas gingivalis with the colony-forming unit assay. Cell compatibility, mRNA expression, and morphology related to human osteoblast-like cells (MG-63) on the coated specimens were determined by the XTT assay and reverse transcriptase-polymerase chain reaction. RESULTS. The number of S. mutans colonies on the TiN, ZrN and $(Ti_{1-x}Zr_x)N$ coated surface decreased significantly compared to those on the non-coated titanium surface (P<0.05). CONCLUSION. The number of P. gingivalis colonies on all surfaces showed no significant differences. TiN, ZrN and $(Ti_{1-x}Zr_x)N$ coated titanium showed antibacterial activity against S. mutans related to initial biofilm formation but not P. gingivalis associated with advanced periimplantitis, and did not influence osteoblast-like cell viability.

  • https://doi.org/10.4047/jap.2015.7.2.166 인용 PDF KSCI