The fretting fatigue behavior in Al–Zn–Mg alloy is investigated under conditions of various equivalent stress amplitudes of cyclic multiaxial loadings and the same contact pressure with a point contact. The ANSYS finite element analysis is used to analyze stress distribution by a numerical study using the 3D finite element method. Fretting regions’ morphology and fracture of specimens are characterized by scanning electron microscopy. Results obtained indicate that at the contact stress of 180 MPa, with increasing of equivalent stress amplitude, the degree of cyclic softening under tension/torsional fretting fatigue loading increases, and the fretting fatigue durability drops with the equivalent stress amplitude. The different equivalent stress amplitudes play a very important role in fretting regions’ morphology and fracture forming. Their influence on the fretting fatigue life is discussed by the comparison of the experimental results.

中文翻译：

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等效应力幅度对Al-Zn-Mg合金多轴微动疲劳行为的影响

在循环多轴载荷的各种等效应力幅度和相同的点接触接触压力条件下，研究了Al-Zn-Mg合金的微动疲劳行为。ANSYS有限元分析用于通过使用3D有限元方法进行的数值研究来分析应力分布。用扫描电子显微镜表征微动区域的形貌和试样的断裂。所得结果表明，在180 MPa的接触应力下，随着等效应力幅值的增加，在拉伸/扭转微动疲劳载荷作用下的循环软化程度增加，而微动疲劳耐久性随等效应力幅值而下降。不同的等效应力幅度在微动区域的形态和裂缝形成中起着非常重要的作用。