Journal of the Korean Society of Propulsion Engineers (한국추진공학회지)

The Korean Society of Propulsion Engineers (한국추진공학회)
권호 표지
DOI QR코드

DOI QR Code

A Study on the Thermal Shock Resistance of Sintered Zirconia for Electron Beam Deposition

전자빔 증착을 위한 소결체 지르코니아의 열충격 저항성 연구

  • Oh, Yoonsuk (Engineering Ceramic Team, Icheon Branch, Korea Institute of Ceramic Engineering and Technology) ;
  • Han, Yoonsoo (Engineering Ceramic Team, Icheon Branch, Korea Institute of Ceramic Engineering and Technology) ;
  • Chae, Jungmin (Engineering Ceramic Team, Icheon Branch, Korea Institute of Ceramic Engineering and Technology) ;
  • Kim, Seongwon (Engineering Ceramic Team, Icheon Branch, Korea Institute of Ceramic Engineering and Technology) ;
  • Lee, Sungmin (Engineering Ceramic Team, Icheon Branch, Korea Institute of Ceramic Engineering and Technology) ;
  • Kim, Hyungtae (Engineering Ceramic Team, Icheon Branch, Korea Institute of Ceramic Engineering and Technology) ;
  • Ahn, Jongkee (Core Technology Group, Power Systems R&D Center, Power System Division, Samsung Techwin) ;
  • Kim, Taehyung (Core Technology Group, Power Systems R&D Center, Power System Division, Samsung Techwin) ;
  • Kim, Donghoon (The 4th R&D Institute, Agency for Defense Development)
  • Received : 2014.12.29
  • Accepted : 2015.05.06
  • Published : 2015.06.01
Download PDF
⟨ Previous Next ⟩

Abstract

Coating materials used in the electron beam (EB) deposition method, which is being studied as one of the fabrication methods of thermal barrier coating, are exposed to high power electron beam at focused area during the EB deposition. Therefore the coating source for EB process is needed to form as ingot with appropriate density and microstructure to sustain their shape and stable melts status during EB deposition. In this study, we tried to find the optimum powder condition for fabrication of ingot of 8 wt% yttria stabilized zirconia which can be used for EB irradiation. It seems that the ingot, which is fabricated through bi-modal type initial powder mixture which consists of tens of micro and nano size particles, was shown better performance than the ingot which is fabricated using monolithic nanoscale powder when exposed to high power EB.

열차폐 코팅(Thermal Barrier Coating) 기술의 하나로 연구되는 전자빔(EB, Electron Beam) 증착에 사용되는 코팅재료는 증착 공정 중에 고출력의 전자빔이 조사되기 때문에, 균일코팅을 위해서는 증착 중 코팅재료의 형상유지 및 안정한 융탕 형성이 필요하며, 이를 위해 적절한 밀도와 미세구조를 갖춘 잉곳(Ingot) 형태의 코팅소스가 요구된다. 본 연구에서는 8 wt%의 이트리아($Y_2O_3$)가 안정화제로 첨가된 지르코니아(8YSZ) 조성을 활용하여, 고출력 전자빔 조사환경에 사용가능한 잉곳제조를 위해 최적의 원료분말 조건을 확보하고자 하였다. 제조된 잉곳시료들에 대한 전자빔 조사 시, 수십 마이크론과 수십 나노 크기의 입자들로 구성된 혼합형 분말로 제조된 잉곳의 경우, 나노크기의 분말만으로 제조된 경우보다 향상된 열충격 저항성을 보였다.

Keywords

References

  1. Evans, A.G., Clarke, D.R. and Levi, C.G., "The Influence of Oxides on the Performance of Advanced Gas Turbines," Journal of the European Ceramic Society, Vol. 28, No. 7, pp. 1405-1419, 2008. https://doi.org/10.1016/j.jeurceramsoc.2007.12.023
  2. Clarke, D.R. and Levi, C.G., "Materials Design for the Next Generation Thermal Barrier Coatings," Annual Review of Materials Research, Vol. 33, No. 1, pp. 383-417, 2003. https://doi.org/10.1146/annurev.matsci.33.011403.113718
  3. Levi, C.G., "Emerging Materials and Processes for Thermal Barrier Systems," Current Opinion in Solid State and Materials Science, Vol. 8, No. 1, pp. 77-91, 2004. https://doi.org/10.1016/j.cossms.2004.03.009
  4. Ren, X. and Pan, W., "Mechanical Properties of High-temperature-degraded Yttria-stabilized Zirconia," Acta Materialia, Vol. 69, pp. 397-406, 2014. https://doi.org/10.1016/j.actamat.2014.01.017
  5. Evans, H.E., "Oxidation failure of TBC Systems: An Assessment of Mechanisms," Surface & Coatings Technology, Vol. 206, No. 7, pp. 1512-1521, 2011. https://doi.org/10.1016/j.surfcoat.2011.05.053
  6. Pan, W., Phillpot, S.R., Wan, C., Chernatynskiy, A. and Qu, Z., "Low Thermal Conductivity Oxides," MRS Bulletin, Vol. 37, No. 10, pp. 917-922, 2012. https://doi.org/10.1557/mrs.2012.234
  7. Wolfe, D.E., Singh, J., Miller, R.A., Eldridge, J.I. and Zhu, D.M., "Tailored Microstructure of EB-PVD 8YSZ Thermal Barrier Coatings with Low Thermal Conductivity and High Thermal Reflectivity for Turbine Applications," Surface & Coatings Technology, Vol. 190, No. 1, pp. 1321-1349, 2005.
  8. Schulz, U., Fritscher, K. and Peters, M., "EB-PVD Y203- and CeO2/Y203-stabilized Zirconia Thermal Barrier Coatings - Crystal Habit and Phase Composition," Surface and Coatings Technology, Vol. 82, No. 3, pp. 259-269, 1996. https://doi.org/10.1016/0257-8972(95)02727-0
  9. Schulz, U., "Phase Transformation in EB PVD Yttria Partially Stabilized Zirconia Thermal Barrier Coatings during Annealing," Journal of the American Ceramic Society, Vol. 83, No. 4, pp. 904-910, 2000. https://doi.org/10.1111/j.1151-2916.2000.tb01292.x
  10. Nicholls, J.R., Lawson, K.J., Johnstone, A. and Rickerby, D.S., "Methods to Reduce the Thermal Conductivity of EB-PVD TBCs," Surface and Coatings Technology, Vol. 151-152, pp. 383-391, 2002. https://doi.org/10.1016/S0257-8972(01)01651-6