Monte Carlo simulation of stress corrosion cracking on a smooth surface of sensitized stainless steel type 304
Monte Carlo simulation of stress corrosion cracking on a smooth surface of sensitized stainless steel type 304
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DOI：
10.1016/j.corsci.2009.06.013
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发表时间：
2009-09
影响因子：
8.3
通讯作者：
K. Tohgo;H. Suzuki;Y. Shimamura;G. Nakayama;T. Hirano
中科院分区：
文献类型：
--
作者：
K. Tohgo;H. Suzuki;Y. Shimamura;G. Nakayama;T. Hirano
应力腐蚀裂纹（SCC）是金属结构材料光滑表面在材料、应力和腐蚀环境的共同作用下，通过微裂纹的萌生、合并、亚临界裂纹扩展和多个大裂纹的形成或最终失效而产生的。在本文中，提出了一个Monte Carlo模拟的SCC过程的基础上的随机性质的微裂纹萌生和断裂力学的概念，裂纹的合并和扩展。程序如下：在给定的空间内，设定可能产生的晶粒尺寸微裂纹的数量，并根据指数分布的随机数分配所有裂纹的产生时间。裂缝的位置和大小分别由均匀随机数和正态随机数指定。根据断裂力学确定裂纹的合并和扩展。在模型中的重点放在半椭圆表面裂纹的影响。根据敏化304不锈钢在高温高纯水中的裂纹弯曲梁试验结果，对微裂纹的萌生速率和聚并条件对数值模拟结果的影响进行了讨论。
Stress corrosion cracking (SCC) on a smooth surface of structural metal materials occurs by initiation and coalescence of micro cracks, subcritical crack propagation and multiple large crack formation or final failure under combination of material, stress and corrosive environment. In this paper, a Monte Carlo simulation of the SCC process is proposed based on stochastic properties for micro crack initiation and concepts in fracture mechanics for crack coalescence and propagation. The procedure is as follows: The possible number of grain-sized micro cracks which can be initiated is set for a given space and initiation times for all cracks are assigned by random numbers based on exponential distribution. Sites and sizes of cracks are assigned by uniform random numbers and normal random numbers, respectively. Coalescence and propagation of cracks are determined based on fracture mechanics. The emphasis in the model is put on the influence of semi-elliptical surface cracks. Numerical simulations are carried out based on the results of creviced-bent-beam tests for sensitized stainless steel type 304 under high-temperature and high-purity water containing dissolved oxygen and the influence of micro crack initiation rate and coalescence condition on the simulation results is discussed.