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New Considerations on Variability of Creep Rupture Data and Life Prediction

크리프 파단 데이터의 변동성에 대한 새로운 고찰과 수명예측

  • 정원택 (부경대학교 대학원 기계설계공학과) ;
  • 공유식 (부경대학교 기계공학부) ;
  • 김선진 (부경대학교 기계공학부)
  • Published : 2009.10.01

Abstract

This paper deals with the variability analysis of short term creep rupture test data based on the previous creep rupture tests and the possibility of the creep life prediction. From creep tests performed by constant uniaxial stresses at 600, 650 and $700^{\circ}C$ elevated temperature, in order to investigate the variability of short-term creep rupture data, the creep curves were analyzed for normalized creep strain divided by initial strain. There are some variability in the creep rupture data. And, the difference between general creep curves and normalized creep curves were obtained. The effects of the creep rupture time (RT) and steady state creep rate (SSCR) on the Weibull distribution parameters were investigated. There were good relation between normal Weibull parameters and normalized Weibull parameters. Finally, the predicted creep life were compared with the Monkman-Grant model.

Keywords

Creep Rupture Time;Steady State Creep Rate;Weibull Distribution;Variability;Life Prediction;Monkman-Grant Model

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