Journal of the Korean Society for Nondestructive Testing (비파괴검사학회지)

The Korean Society for Nondestructive Testing (한국비파괴검사학회)
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Detection and Evaluation Technique of Hydrogen Attack

수소손상 검출과 평가기술

  • Won, Soon-Ho (Nondestructive Evaluation Group, Korea Institute of Machinery and Materials) ;
  • Hyun, Yang-Ki (Nondestructive Evaluation Group, Korea Institute of Machinery and Materials) ;
  • Lee, Jong-O (Nondestructive Evaluation Group, Korea Institute of Machinery and Materials) ;
  • Cho, Kyung-Shik (Nondestructive Evaluation Group, Korea Institute of Machinery and Materials) ;
  • Lee, Jae-Do (Nondestructive Evaluation Group, Korea Institute of Machinery and Materials)
  • 원순호 (한국기계연구원 비파괴평가그룹) ;
  • 현양기 (한국기계연구원 비파괴평가그룹) ;
  • 이종오 (한국기계연구원 비파괴평가그룹) ;
  • 조경식 (한국기계연구원 비파괴평가그룹) ;
  • 이재도 (한국기계연구원 비파괴평가그룹)
  • Published : 2002.02.28
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Abstract

The presence of hydrogen in industrial plants is a source of damage. Hydrogen attack is one such form of degradation and often causing large tube ruptures that necessitate an immediate shutdown. Hydrogen attack may reduce the fracture toughness as well as the strength of steels. This reduction is caused partially by the presence of cavities and microcracks at the grain boundaries. In the past several techniques have been used with limited results. This paper describes the application of an ultrasonic velocity and attenuation in hydrogen damage. Ultrasonic tests showed a decrease in wave velocity and an increase in attenuation. Such results demonstrate the potential for ultrasonic nondestructive testing to quantify damage. Based on this study, reliable recommendation is suggested to detect hydrogen attack.

산업현장에서 수소는 설비를 손상시킬 수 있는 주원인 중의 하나이며, 종종 설비를 파괴시키는 사고를 발생시킨다. 수소손상에 의한 결정립계의 공동 또는 미세균열은 강재의 파괴인성과 강도를 떨어뜨리는 원인이 되고, 따라서 과거 제한적인 방법으로 수소손상을 평가하기 위한 시도가 수행되었다. 본 연구에서는 초음파를 적용하여 수소손상을 검출하고 평가하기 위한 연구를 수행하였다. 미세조직 시험에 의해 확인된 시험편을 이용하여 초음파의 속도와 감쇠계수를 구한 결과, 수소손상에 의해서 초음파 속도는 감소하고 감쇠는 현저하게 증가하는 것으로 나타났다. 이러한 결과를 바탕으로 수소손상을 검출하기 위한 신뢰성 있는 평가법을 제시하였다.

Keywords

References

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