Fatigue fracture is the one of the most common failures of mechanical components. This is caused by the initiation and growth of cracks. In this study, mixed mode-I/III fatigue crack growth is studied experimentally and numerically for cylindrical specimen with a stress ratio R = 0.1 for both loading. Digital camera was used to monitoring the crack growth path in the experimental studies. The crack growth path, crack tip profiles, variations of stress intensity factors (SIF) and equivalent SIF were calculated by Ansys, FCPAS and Solidworks software and results were compared with experimental data. Modeling, meshing and problem solving were performed using Ansys, and the resulting SIF and equivalent SIF along the crack front were calculated using FCPAS that is employed with enriched elements. It is seen that the criteria from literature (Richard, Tanaka, Pook and Ayhan-Demir) can be successfully applied to the problem. The results show that very good agreements are obtained between the results of the simulation and experiment in terms of both evolving the crack growth paths and crack tips. The presented methodology can be used to predict the both surface and interior the crack path for various loading conditions and applications.

中文翻译：

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混合模式载荷下裂纹扩展的实验与数值研究

疲劳断裂是机械部件最常见的故障之一。这是由裂纹的产生和扩展引起的。在这项研究中，实验研究和数值研究了两种载荷下圆柱体试样的应力比R = 0.1的混合模式I / III疲劳裂纹扩展。在实验研究中，使用数码相机来监测裂纹扩展路径。利用Ansys，FCPAS和Solidworks软件计算了裂纹扩展路径，裂纹尖端轮廓，应力强度因子（SIF）和等效SIF的变化，并将结果与​​实验数据进行了比较。使用Ansys进行建模，网格划分和问题求解，并使用FCPAS（与富集元素一起使用）计算沿裂纹前沿的所得SIF和等效SIF。从文献（Richard，Tanaka，Pook和Ayhan-Demir）可以成功地应用于此问题。结果表明，在模拟结果和实验结果之间，在裂纹扩展路径和裂纹尖端的演化方面都取得了很好的一致性。所提出的方法可用于预测各种载荷条件和应用的表面和内部裂纹路径。