Modeling Creep Behavior and Life by Damage Mechanics

손상역학에 의한 크리프 거동 및 수명 모델링

Sin, Chang-Hwan;Jeong, Il-Seop;Chae, Yeong-Seok

  • Published : 2000.07.01


Commercially pure copper is tested to obtain creep curves at 2500C. Constitutive relations adopting continuum damage mechanics concept is found to be appropriate to model the creep defor mation up to the tertiary stage. Microscopic observation by SEM reveals that creep condition induces cavities and microcracks subsequently. The constitutive equations along with evaluated creep parameters are implemented into finite element analysis code. The analysis reproduces creep curves under step loading as well as constant loading with reasonable accuracy. Distribution and evolution of damage under creep loading are numerically simulated for two different types of notched specimen. Predicted creep life agrees quite well with rupture test results. The influence of mesh size at notch tip on rupture time prediction is studied, and a degree of refinement is suggested for the specific notched specimens.


Creep;Copper;Damage Mechanics;FEM


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