Prediction of Inner Cracking Behavior in Heat-Resistant Steel under Creep-Fatigue Condition by Means of Three-Dimensional Numerical Simulation
Prediction of Inner Cracking Behavior in Heat-Resistant Steel under Creep-Fatigue Condition by Means of Three-Dimensional Numerical Simulation
复制标题
三维数值模拟预测蠕变疲劳条件下耐热钢的内部裂纹行为
DOI：
10.1007/978-94-015-9628-2_8
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
R. Ohtani
中科院分区：
文献类型：
--
作者：
N. Tada;R. Ohtani
图1显示了304型奥氏体不锈钢的非弹性应变范围与高温疲劳失效循环次数之间的关系[1]。从小裂纹的位置来看，蠕变疲劳断裂可分为两种类型。一种是“表面裂纹型”，在图1中用O表示，其中小的晶间裂纹仅在试样表面上萌生，它们的生长和合并导致最终断裂。已知这种类型出现在具有相对高的应变率（或应力）的中间温度下。由于这种类型的裂纹仅在试样表面萌生，因此可以通过裂纹的表面观察来评估蠕变疲劳损伤。另一方面，随着温度的升高和/或应变速率（或应力）的降低，仅限于试样表面的开裂区域向内延伸，最后，小裂纹几乎均匀地出现在整个试样中。
Figure 1 shows the relationship between inelastic strain range and the number of cycles to failure for high-temperature fatigue of Type 304 austenitic stainless steel [1]. From the viewpoint of the location of small cracks, creep-fatigue fracture can be divided into two types. One is a “surface cracking type” indicated by O in Figure 1, in which small intergranular cracks are initiated only on the surface of the specimen, and their growth and coalescence bring about the final fracture. It is known that this type appears at intermediate temperatures with relatively high strain rates (or stresses). As the cracks are initiated only on the surface of the specimen in this type, creep-fatigue damage can be evaluated by surface observation of cracks. On the other hand, with increasing the temperature and/or decreasing the strain rate (or stress), the region of cracking, which was limited to the surface of the specimen, extends inward and, finally, small cracks appear almost uniformly throughout the specimen.