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Sliding Wear Properties of Graphite as Sealing Materials for Cut off Hot Gas

고온차단 기밀용 그라파이트의 고온 미끄럼마모 특성 평가

  • Kim, YeonWook (School of Mechanical Design Engineering, Chungnam Nat'l Univ.) ;
  • Kim, JaeHoon (School of Mechanical Design Engineering, Chungnam Nat'l Univ.) ;
  • Yang, HoYeong (School of Mechanical Design Engineering, Chungnam Nat'l Univ.) ;
  • Park, SungHan (Agency for Defense Development) ;
  • Lee, HwanKyu (Agency for Defense Development) ;
  • Kim, BumKeun (Dept. of Mechanical and Automotive Engineering, Inje Univ.) ;
  • Lee, SeungBum (Dept. of Mechanical and Automotive Engineering, Inje Univ.) ;
  • Kwak, JaeSu (Dept. of Aerospace and Mechanical Engineering, Korea Aerospace Univ.)
  • 김연욱 (충남대학교 기계설계공학과) ;
  • 김재훈 (충남대학교 기계설계공학과) ;
  • 양호영 (충남대학교 기계설계공학과) ;
  • 박성한 (국방과학연구소) ;
  • 이환규 (국방과학연구소) ;
  • 김범근 (인제대학교 기계자동차공학부) ;
  • 이성범 (인제대학교 기계자동차공학부) ;
  • 곽재수 (한국항공대학교 항공우주 및 기계공학부)
  • Received : 2013.03.29
  • Accepted : 2013.09.12
  • Published : 2013.11.01

Abstract

Sealing structure to prevent flowing hot gas into the driving device, located between the driving shaft and the liner of On-Off valve for controlling the hot gas flow path was studied. Wear occurs due to the constant movement of the driving shaft controlled by actuator on graphite as the sealing material. In this paper, the dynamic wear behavior in high temperature of graphite(HK-6) to be used as sealing material was evaluated. Reciprocating wear test was carried out for the graphite(HK-6) to the relative motion between shaft materials(W-25Re). The results of friction coefficient and specific wear rate according to contact load, sliding speed at room temperature and $485^{\circ}C$ considering the actual operating environment were evaluated. Through the SEM analysis of the worn surface, third body as lubricant films were observed and lubricant effect of third body was considered.

Keywords

Sealing Materials;Graphite;Wear Debris;Solid Lubricant;Third Body;Elevated Temperature

Acknowledgement

Supported by : 국방과학연구소

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