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Estimation of Transient Creep C(t)-integrals for SE(B) Specimen Under Elastic-Plastic-Creep Conditions

탄성-소성-크리프 상태에서 SE(B) 시편의 천이크리프 C(t)-적분 평가

  • Lee, Han-Sang (Dept. of Mechanical Engineering, Korea Univ.) ;
  • Je, Jin-Ho (Dept. of Mechanical Engineering, Korea Univ.) ;
  • Kim, Dong-Jun (Dept. of Mechanical Engineering, Korea Univ.) ;
  • Kim, Yun-Jae (Dept. of Mechanical Engineering, Korea Univ.)
  • Received : 2015.04.23
  • Accepted : 2015.06.24
  • Published : 2015.09.01

Abstract

In this paper, we estimate the time-dependent C(t) integrals under elastic-plastic-creep conditions. Finite-element (FE) transient creep analyses have been performed for single-edge-notched-bend (SEB) specimens. 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 exponents in the power-law creep and plasticity to elastic-plastic-creep behavior. To estimate the C(t) integrals, we compare the FE analysis results with those obtained using formulas. In this paper, we propose a modified equation to predict the C(t) integrals for the case of creep exponents that are different from the plastic exponent.

Keywords

Elastic-plastic-creep;C-integrals;Transient Creep;FE Analysis;SEB Specimen

Acknowledgement

Supported by : 한국연구재단

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