수치 해석 방법을 이용한 크리프 균열 진전에 미치는 1차 크리프 속도의 영향 평가 : 1차 크리프 속도를 고려한 크리프 균열 진전의 유한요소 = Finite Element Analysis of Creep Crack Growth Behavior Including Primary Creep Rate

다국어 초록 (Multilingual Abstract)

An elastic-viscoplastic finite element analysis is performed to investigate detailed growth behavior of creep cracks and the numerical results are compared with experimental results. In Cr-Mo steel stress fields obtained from the crack growth method by mesh translation were compared with both cases the secondary creep rate is only used as creep material property and the primary creep rate is included. Analytical stress fields, Riedel-Rice(RR) field, Hart-Hui-Riedel(HR) field and Prime(named in here) field, and the results obtained by numerical method were evaluated in details. Time vs. Stress at crack tip was showed and crack tip stress fields were plotted. These results were compared with analytical stress fields. There is no difference of stress distribution at remote region between the case of 1st creep rate + 2nd creep rate and the case of 2nd creep rate only. In case of slow velocity of crack growth, the effect of 1st creep rate is larger than the one of fast crack growth rate. Stress fields at crack tip region are, in order, Prime field, HR field and RR field from crack tip.