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Fracture Behavior of Graphite Material at Elevated Temperatures Considering Oxidation Condition

산화환경을 고려한 흑연 내열재의 고온파단특성

  • Choi, Hoon Seok (Dept. of Mechanical Design Engineering, ChungNam Nat'l Univ.) ;
  • Kim, Jae Hoon (Dept. of Mechanical Design Engineering, ChungNam Nat'l Univ.) ;
  • Oh, Kawng Keun (Dept. of Mechanical Design Engineering, ChungNam Nat'l Univ.)
  • 최훈석 (충남대학교 기계설계공학과) ;
  • 김재훈 (충남대학교 기계설계공학과) ;
  • 오광근 (충남대학교 기계설계공학과)
  • Received : 2015.01.07
  • Accepted : 2015.08.24
  • Published : 2015.11.01

Abstract

Graphite material has been widely used for making the rocket nozzle throat because of its excellent thermal properties. However, when compared with typical structural materials, graphite is relatively weak with respect to both strength and toughness, owing to its quasi-brittle behavior, and gets oxidized at $450^{\circ}C$. Therefore, it is important to evaluate the thermal and mechanical properties of this material for using it in structural applications. This study presents an experimental method to investigate the fracture behavior of ATJ graphite at elevated temperatures. In particular, the effects of major parameters such as temperature, loading, and oxidation conditions on strength and fracture characteristics were investigated. Uniaxial compression and tension tests were conducted in accordance with the ASTM standard at room temperature, $500^{\circ}C$, and $1,000^{\circ}C$. Fractography analysis of the fractured specimens was carried out using an SEM.

Keywords

ATJ Graphite;Oxidation;Uniaxial Compression;Uniaxial Tension;Silicon Carbide;Oxidation Protection Coating;SEM

Acknowledgement

Supported by : 충남대학교

References

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