A representative volume element (RVE) based multi-scale method is proposed to investigate the mechanism of fatigue crack propagation by the molecular dynamics (MD) and the extended finite element methods(XFEM) in this study. An atomic model of carbon steel plate is built to study the behavior of fatigue crack at the micro scale by MD method. Then the RVE model for fatigue crack propagation should be built by fitting the data which was obtained from the MD result with the Paris law model. Moreover, the effect of micro-structural defects including interstitial atoms, vacancies have also been considered in this study. The results indicate that the micro-structural defects can deeply influence the values of Paris law constants and the life of the specimen can be evaluated by the proposed method.
翻译:提议了一种基于代表性体积元素(RVE)的多尺度方法,以调查分子动态(MD)的疲劳裂痕传播机制以及本研究中扩大的有限元素方法(XFEM),碳钢板原子模型的构建是为了研究微量体积疲劳裂痕行为;然后,疲劳裂痕传播RVE模型的构建方法应是将MD结果获得的数据与巴黎法律模型相匹配;此外,本研究还考虑了微结构缺陷(包括间原子)的影响;研究结果表明,微结构缺陷可以深刻影响巴黎法律常数的价值,而标本的生命期可以通过拟议方法加以评估。