Journal of the Korean institute of surface engineering (한국표면공학회지)

The Korean Institute of Surface Engineering (한국표면공학회)
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Formation of YSZ Coatings Deposited by Suspension Vacuum Plasma Spraying

서스펜션 진공 플라즈마 용사법을 통한 YSZ 코팅의 형성

  • Yoo, Yeon Woo (Advanced Plasma Processing Department, Surface Technology Division, Korea Institute of Materials Science(KIMS)) ;
  • Byon, Eungsun (Advanced Plasma Processing Department, Surface Technology Division, Korea Institute of Materials Science(KIMS))
  • 유연우 (재료연구소 표면기술연구본부 플라즈마공정연구실) ;
  • 변응선 (재료연구소 표면기술연구본부 플라즈마공정연구실)
  • Received : 2017.11.02
  • Accepted : 2017.12.14
  • Published : 2017.12.31
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Abstract

As increasing thermal efficiency of the gas turbine, the performance improvement of thermal barrier coatings is also becoming important. Ytrria stabilized zirconia(YSZ) is the most popular materials for ceramic top coating because of its low thermal conductivity. In order to enhance the performance of thermal barrier coatings for hot sections in the gas turbine, suspension plasma spraying was developed in order to feed nano-sized powders. YSZ coatings formed by suspension plasma spraying showed better performance than YSZ coatings due to its exclusive microstructure. In this research, two YSZ coatings were deposited by suspension vacuum plasma spraying at 400 mbar and 250 mbar. Microstructures of YSZ coatings were analyzed by scanning electron image(SEM) on each spraying conditions, respectively. Crystalline structure transformation was not detected by X-ray diffraction. Thermal conductivity of suspension vacuum plasma sprayed YSZ coatings were measured by laser flash analysis. Thermal conductivity of suspension vacuum plasma sprayed YSZ coatings containing horizontally oriented nano-sized pores and vertical cracks showed $0.6-1.0W/m{\cdot}K$, similar to thermal conductivity of YSZ coatings formed by atmospheric plasma spraying.

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References

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