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Evaluation of the Mechanical Characteristics According to the Curvature of Thermal Barrier Coating

가스터빈 블레이드 열차폐코팅의 곡률에 따른 기계적 특성 평가

  • Lee, Jeng-Min (School of Mechanical Engineering, Sungkyunkwan Univ.) ;
  • Seok, Chang-Sung (School of Mechanical Engineering, Sungkyunkwan Univ.) ;
  • Koo, Jae-Mean (School of Mechanical Engineering, Sungkyunkwan Univ.) ;
  • Kim, Sung Hyuk (School of Mechanical Engineering, Sungkyunkwan Univ.) ;
  • Zhen, Guo (School of Mechanical Engineering, Sungkyunkwan Univ.) ;
  • Tao, Shen (School of Mechanical Engineering, Sungkyunkwan Univ.) ;
  • Moon, Wonki (School of Mechanical Engineering, Sungkyunkwan Univ.)
  • 이정민 (성균관대학교 기계공학부) ;
  • 석창성 (성균관대학교 기계공학부) ;
  • 구재민 (성균관대학교 기계공학부) ;
  • 김성혁 (성균관대학교 기계공학부) ;
  • ;
  • ;
  • 문원기 (성균관대학교 기계공학부)
  • Received : 2014.03.19
  • Accepted : 2014.10.12
  • Published : 2014.12.01

Abstract

A thermal barrier coating (TBC) prevents heat directly transferring from a high-temperature flame to a substrate. The TBC system comprises a top coating and bond coating. TBC technology reduces the substrate surface temperature by about $100{\sim}170^{\circ}C$. In the TBC system, internal stress is generated by the difference in thermal expansion coefficients of the substrate and coating. The internal stress also differs according to the shape and position of the blade. In this study, finite element analysis was performed for different curvatures of coin-shaped specimens, which are commonly used for thermal fatigue tests, and the changes in internal stress of the TBC system were compared. Based on the results, the curvature at which the minimum stress occurs was derived, and the thermal stress was confirmed to increase with the difference between a given curvature and the curvature with the minimum stress.

Keywords

Thermal Barrier Coating;Finite Element Analysis;Gas Turbine Blade

Acknowledgement

Supported by : National Research Foundation of Korea (NRF)

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