대한기계학회논문집A (Transactions of the Korean Society of Mechanical Engineers A)

  • 제37권3호
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  • Pages.353-358
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  • 2013
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  • 1226-4873(pISSN)
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  • 2288-5226(eISSN)
대한기계학회 (The Korean Society of Mechanical Engineers)
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등온열처리에 따른 2.25Cr-1Mo강의 초음파 특성 변화

Change in Ultrasonic Characteristics with Isothermal Heat Treatment of 2.25Cr-1Mo Steel

  • 남영현 (한국표준과학연구원 재료측정표준센터) ;
  • 백운봉 (한국표준과학연구원 재료측정표준센터) ;
  • 박종서 (한국표준과학연구원 재료측정표준센터) ;
  • 남승훈 (한국표준과학연구원 재료측정표준센터)
  • Nam, Young-Hyun (Center for Material Measurement, Korea Research Institute of Standards and Science) ;
  • Baek, Un-Bong (Center for Material Measurement, Korea Research Institute of Standards and Science) ;
  • Park, Jong-Seo (Center for Material Measurement, Korea Research Institute of Standards and Science) ;
  • Nahm, Seung-Hoon (Center for Material Measurement, Korea Research Institute of Standards and Science)
  • 투고 : 2012.08.02
  • 심사 : 2012.09.10
  • 발행 : 2013.03.01
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초록

본 논문은 등온열처리 온도 및 시간에 따른 2.25Cr-1Mo강의 초음파 특성 변화를 조사하였다. Charpy 충격시험과 경도시험이 3종류의 열처리조건을 가지는 각 시편들에 대하여 실시되었다. 종파를 이용한 펄스-에코법이 초음파의 감쇠와 속도 측정에 사용되었다. 연취성천이온도(FATT)는 등온열처리 시간이 길어짐에 따라 증가하였는데, 이는 인성이 감소되고 있음을 의미한다. 등온열처리 시간과 온도의 증가와 함께 종파의 속도 및 초음파의 감쇠계수는 증가하였다.

The ultrasonic characteristics of 2.25Cr-1Mo steel were investigated in relation to the isothermal heat treatment temperature and time. Charpy impact tests and hardness tests were conducted on individual specimens with three different heat treatment conditions. A pulse-echo method with longitudinal waves was used to measure the attenuation and velocity of ultrasonic waves. The FATT (fracture appearance transition temperature) increased with an increase in the isothermal heat treatment time, which implies that the toughness decreased. As the isothermal heat treatment time and temperature increased, the longitudinal wave velocity and ultrasonic attenuation coefficient were raised.

키워드

참고문헌

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