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Thermal Shock Resistance According to the Manufacturing Process of Lanthanum Gadolinium Zirconate Ceramic Igot for Thermal Barrier Coating by Electron Beam in the La2O3-Gd2O3-ZrO2 System

전자빔 증착 열차폐 코팅용 란타늄-가돌리늄 지르코네이트(La2O3-Gd2O3-ZrO2계) 세라믹 잉곳의 제조공정에 따른 열충격 저항성

  • Choi, Seona (Engineering Ceramic Center, Korea Institute of Ceramic Engineering and Technology) ;
  • Chae, Jungmin (Engineering Ceramic Center, Korea Institute of Ceramic Engineering and Technology) ;
  • Kim, Seongwon (Engineering Ceramic Center, Korea Institute of Ceramic Engineering and Technology) ;
  • Lee, Sungmin (Engineering Ceramic Center, Korea Institute of Ceramic Engineering and Technology) ;
  • Han, Yoonsoo (Engineering Ceramic Center, Korea Institute of Ceramic Engineering and Technology) ;
  • Kim, Hyungtae (Engineering Ceramic Center, Korea Institute of Ceramic Engineering and Technology) ;
  • Jang, Byungkoog (Research Center for Structural Materials, National Institute for Materials Science) ;
  • Oh, Yoonsuk (Engineering Ceramic Center, Korea Institute of Ceramic Engineering and Technology)
  • 최선아 (한국세라믹기술원 이천분원 엔지니어링세라믹센터) ;
  • 채정민 (한국세라믹기술원 이천분원 엔지니어링세라믹센터) ;
  • 김성원 (한국세라믹기술원 이천분원 엔지니어링세라믹센터) ;
  • 이성민 (한국세라믹기술원 이천분원 엔지니어링세라믹센터) ;
  • 한윤수 (한국세라믹기술원 이천분원 엔지니어링세라믹센터) ;
  • 김형태 (한국세라믹기술원 이천분원 엔지니어링세라믹센터) ;
  • 장병국 (물질재료연구기구(NIMS) 구조재료센터) ;
  • 오윤석 (한국세라믹기술원 이천분원 엔지니어링세라믹센터)
  • Received : 2017.11.15
  • Accepted : 2017.12.18
  • Published : 2017.12.31
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Abstract

The ingot fabrication conditions related with the thermal shock bearing phase and microstructure have investigated for the rare earth zirconate ceramic material, lanthanum gadolinium zirconate, as a thermal barrier coating using electron beam evaporation method. The thermal shock resistance of the prepared ingot was evaluated by high energy electron beam irradiation. The rare earth zirconate ceramic powder was prepared by controlling the raw material powder composition of $La_2O_3$, $Gd_2O_3$ and $ZrO_2$ so as to have a composition of $(La_{0.3}Gd_{0.7})_2Zr_2O_7$ which was selected from the former study. Ingot samples were prepared under two conditions. The first condition is prepared by sintering the prepared powder mixture to form an ingot. The second condition is prepared by calcining the prepared powder mixture to form a composite phase and then sintering to form an ingot. X-ray diffraction(XRD) and Scanning Electron Microscope(SEM) were used to analyze phase forming behavior and microstructure of ingot samples. Nanoindentation method used to obtain elastic modulus and hardness of each ingot specimen. Also the stress distribution of ingot was simulated by using FEM method assuming the ingot surface was exposed to electron beam. As a results, in the case of an ingot having a network-shaped microstructure in which relatively coarse pores are included, it seems that the thermal shock resistance was higher than in the case of an ingot having a microstructure composed of relatively fine grains only or particles with the similar level size when the high energy electron beam irradiation.

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References

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