Fatigue is a major cause of failure in several industries, and in many practical cases, local mixed-mode conditions prevail at the crack front. The effect of plane mode mixity on the crack growth rate and crack growth direction has been investigated. Fatigue crack growth experiments have been conducted on aluminum alloy Al5083-H111 for several mode mixities. A fixture was manufactured in order to apply the different combinations of mode I and II by changing loading angle. Afterward, three-dimensional simulations have been implemented using the Zencrack software. Based on numerical simulations, new relations are proposed to estimate stress intensity factors for compact tension shear geometry by modifying Richard’s equations [1].

疲劳是导致多个行业失败的主要原因，在许多实际情况下，局部混合模式条件普遍存在于裂纹前沿。研究了平面模式混合对裂纹扩展速率和裂纹扩展方向的影响。已经对铝合金Al5083-H111进行了几种模式混合的疲劳裂纹扩展实验。制造了一种夹具，以通过更改加载角度来应用模式I和II的不同组合。之后，使用Zencrack软件进行了三维模拟。在数值模拟的基础上，提出了新的关系，通过修改Richard方程[1]来估算紧凑型拉伸剪切几何结构的应力强度因子。