Determination of New Parameter for Materials Degradation Using Continuous Indentation Testing Technique

연속압입 시험기법을 이용한 석유화학설비 경년손상의 새로운 평가변수 고찰

  • Jang, Jae-Il ;
  • Choi, Yeol ;
  • Son, Dongil ;
  • Lee, Yun-Hee (School of Materials Science and Engineering, Seoul National School) ;
  • Kwon, Dongil (School of Materials Science and Engineering, Seoul National School) ;
  • Kim, Jeoung-Tae
  • 장재일 ((주)프론틱스 부설연구소) ;
  • 최열 ((주)프론틱스 부설연구소) ;
  • 손동일 ((주)프론틱스 부설연구소) ;
  • 이윤희 (서울대학교 재료공학부) ;
  • 권동일 (서울대학교 재료공학부) ;
  • 김정태 (두산중공업 기술연구원)
  • Published : 2002.05.01


Newly developed continuous indentation technique has made nondestructive assessment of tensile properties possible. The present study was undertaken to determine new parameters for indicating time-dependent material degradation of petro-chemical plant. Continuous indentation tests were performed for Cr-Ni steel and Cr-Mo steel which are widely used as facilities of petro-chemical plant. From the results, it was found that yield strength and tensile strength cannot be used as general degradation parameters because the changes in the strengths with aging time didn't show any tendency. On the other hand, work hardening exponent and yield ratio showed consistent tendency with increasing aging time. Therefore, nam attention of this work was paid on them as new degradation parameters, and the in-field applicability of the parameters was evaluated and discussed.


Continuous Indentation Test;Nondestructive Evaluation;Time-Dependent Degradation;Work Hardening Exponent;Yield Ratio;Cr-Ni Steel;Cr-Mo Steel


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