Journal of the Korean Society of Propulsion Engineers (한국추진공학회지)

The Korean Society of Propulsion Engineers (한국추진공학회)
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Compression Fracture Behavior of ATJ Graphite for Rocket Nozzle throat

로켓 노즐목에 사용하는 ATJ 흑연의 압축 파단 특성

  • Choi, Hoonseok (Department of Mechanical Design Engineering, Chungnam National University) ;
  • Kim, Jaehoon (Department of Mechanical Design Engineering, Chungnam National University) ;
  • Kim, Yeonwook (Department of Mechanical Design Engineering, Chungnam National University) ;
  • Seo, Bohwi (Department of Mechanical Design Engineering, Chungnam National University) ;
  • Moon, Soonil (Advanced Propulsion Technology Center, Agency for Defense Development)
  • Received : 2013.12.09
  • Accepted : 2014.07.07
  • Published : 2014.08.01
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Abstract

Graphite is commonly used for rocket nozzle. The purpose of the present study is to evaluate compression fracture behavior of ATJ graphite. Uniaxial compression test is conducted in accordance with ASTM C 695 in the range of R.T to $900^{\circ}C$. The size effects of specimen on the compressive strength and fracture behavior were investigated. Two types of cylindrical specimen, i.e., where the diameter to length ratio is 1:2 (ASTM C 695 specimen) or 1:1, were tested at room temperature.

본 연구의 흑연은 로켓 노즐목 재료로 많이 사용되는 것으로써 온도, 가공성 및 무게 측면에서 유리하다. 하지만 고온 및 고압상태에서 고속으로 취성파괴 되므로 설계 시 구조적 안정성을 충분히 확보해야 한다. 본 연구에서는 로켓 노즐목에 이용되는 ATJ 흑연의 압축 파괴 거동에 대해 연구했다. 상온 및 고온에서 ASTM C 695에 준하여 일축 압축 시험을 수행하였다. 또한 시편의 단면적 변화에 의한 압축강도 및 파단특성을 분석하였다.

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References

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