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Estimation of Transient Creep Crack-tip Stress Fields for SE(B) specimen under Elastic-Plastic-Creep Conditions

탄성-소성-크리프 상태에서 SE(B) 시편의 천이크리프 균열 선단 응력장 평가

  • Lee, Han-Sang (Department of Mechanical Engineering, Korea Univ.) ;
  • Je, Jin-Ho (Department of Mechanical Engineering, Korea Univ.) ;
  • Kim, Dong-Jun (Department of Mechanical Engineering, Korea Univ.) ;
  • Kim, Yun-Jae (Department of Mechanical Engineering, Korea Univ.)
  • Received : 2015.05.06
  • Accepted : 2015.06.28
  • Published : 2015.10.01

Abstract

This paper estimates the time-dependent crack-tip stress fields under elastic-plastic-creep conditions. We perform Finite-Element (FE) transient creep analyses for a Single-Edge-notched-Bend (SEB) specimen. We investigate the effect of the initial plasticity on the transient creep by systematically varying the magnitude of the initial step-load. We consider both the same stress exponent and different stress exponent in the power-law creep and plasticity to determine the elastic-plastic-creep behaviour. To estimation of the crack-tip stress fields, we compare FE analysis results with those obtained numerically formulas. In addition, we propose a new equation to predict the crack-tip stress fields when the creep exponent is different from the plastic exponent.

Keywords

Elastic-Plastic-Creep;Crack-Tip Stress Fields;Transient Creep;FE Analysis;SEB Specimen

Acknowledgement

Supported by : 한국연구재단

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