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Creep Characterization of 9Cr1Mo Steel Used in Super Critical Power Plant by Conversion of Stress and Strain for SP-Creep Test

SP-Creep 시험의 응력 및 변형률 환산에 의한 초임계압 발전설비용 9Cr1Mo강의 크리프 특성 평가

  • 백승세 (전북대학교 대학원 정밀기계공학과) ;
  • 박정훈 (전북대학교 대학원 정밀기계공학과) ;
  • 유효선 (전북대학교 기계항공시스템공학부, 자동차신기술연구센터)
  • Published : 2006.09.01

Abstract

Due to the need of increasing thermal efficiency, supercritical pressure and temperature have been utilized in power plants. It is well known that 9Cr1Mo steel is suitable fer use in power plants operating at supercritical conditions. Therefore, to ensure the safety and the soundness of the power plant, creep characterization of the steel is important. In this study, the creep characterization of the gCr1Mo steel using small punch creep(SP-Creep) test has been described. The applied load and the central displacement of the specimen in SP-Creep test have been converted to bearing stress and strain of uc, respectively. The converted SP-Creep curves clearly showed the typical three-stage behavior of creep. The steady-state creep rate and the rupture time of the steel logarithmically changed with the bearing stress and satisfied the Power law relationship. Furthermore, the Larson-Miller parameter of the SP-Creep test agreed with that of the tensile creep test. From the comparison with low Cr-Mo steels, the creep characteristics of 9Cr1Mo steel proved to be superior. Thus, it can be confirmed that the 9Cr1Mo steel is suitable for supercritical power plant.

Keywords

SP-Creep Test;Creep Characteristics;Bearing Stress;Power Law Relationship;Creep date;Rupture Time;Stress Exponent;Larson-Miller Parameter;9Cr1Mo Steel

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