• 제목/요약/키워드: yttria stabilized zirconia

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Synthesis of Yttria Stabilized Zirconia by Sol-gel Precipitation Using PEG and PVA as Stabilizing Agent

  • Bramhe, Sachin N.;Lee, Young Pil;Nguyen, Tuan Dung;Kim, Taik-Nam
    • 한국재료학회지
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    • 제23권8호
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    • pp.441-446
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    • 2013
  • There is increasing interest in zirconia as a dental material due to its aesthetics, as well as the exceptionally high fracture toughness and high strength that are on offer when it is alloyed with certain oxides like yttria. In recent years, many solution based chemical synthesis methods have been reported for synthesis of zirconia, of which the sol-gel method is considered to be best. Here, we synthesize zirconia by a sol gel assisted precipitation method using either PEG or PVA as a stabilizing agent. Zirconia sol is first synthesized using the hydrothermal method. We used NaOH as the precipitating agent in this method because it is easy to remove from the final solution. Zirconium and yttrium salts are used as precursors and PEG or PVA are used as stabilizers to separate the metal ions. The resulting amorphous zirconia powder is calcined at $900^{\circ}C$ for 2 h to get crystallized zirconia. XRD analysis confirmed the partially stabilized zirconia synthesis in all the synthesized powders. SEM was taken to check the morphology of the powder synthesized using either PEG or PVA as a stabilizing agent and finally the transparency was calculated. The results confirmed that the powder synthesized with 10 % PVA as the stabilizing agent had highest percentage of transparency among all the synthesized powder.

서스펜션 플라즈마 용사를 이용한 이트리아 안정화 지르코니아 (7.5 wt% Y2O3-ZrO2) 코팅 증착 및 특성 (Fabrication and Characteristics of Yttria-stabilized Zirconia (7.5 wt% Y2O3-ZrO2) Coating Deposited via Suspension Plasma Spray)

  • 이원준;권창섭;김성원;오윤석;김형태;임대순
    • 한국분말재료학회지
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    • 제20권6호
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    • pp.445-452
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    • 2013
  • Yttria-stabilized zirconia (YSZ) coatings are fabricated via suspension plasma spray (SPS) for thermal barrier applications. Three different suspension sets are prepared by using a planetary mill as well as ball mill in order to examine the effect of starting suspension on the phase evolution and the microstructure of SPS prepared coatings. In the case of planetary-milled commercial YSZ powder, a deposited thick coating turns out to have a dense, vertically-cracked microstructure. In addition, a dense YSZ coating with fully developed phase can be obtained via suspension plasma spray with suspension from planetary-milled mixture of $Y_2O_3$ and $ZrO_2$.