Wang Jun, Xu Hong, Su Tiexiong, Zhang Yi, Guo Zhen, Mao Huping, Zhang Yangang
School of Mechanical and Power Engineering, North University of China, Taiyuan 030051, China.
School of Materials Science and Engineering, North University of China, Taiyuan 030051, China.
Materials (Basel). 2016 Dec 5;9(12):984. doi: 10.3390/ma9120984.
An investigation was carried out in order to study the fretting fatigue behavior of an AlSi9Cu2Mg aluminum alloy. The fretting fatigue tests of AlSi9Cu2Mg were performed using a specially designed testing machine. The failure mechanism of fretting fatigue was explored by studying the fracture surfaces, fretting scars, fretting debris, and micro-hardness of fretting fatigue specimens using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and micro Vickers hardness test techniques. The experimental results show that the fretting fatigue limit (42 MPa) is significantly reduced to approximately 47% of the plain fatigue limit (89 MPa) under 62.5 MPa contact pressure. Furthermore, the fretting fatigue life decreases with increasing alternating stress and increasing contact pressure. The examination results suggest that the stress concentrates induced by oxidation-assisted wear on the contact interface led to the earlier initiation and propagation of crack under the fretting condition.
为了研究AlSi9Cu2Mg铝合金的微动疲劳行为，开展了一项调查。使用专门设计的试验机对AlSi9Cu2Mg进行微动疲劳试验。通过利用扫描电子显微镜（SEM）、能量色散X射线光谱仪（EDX）和显微维氏硬度测试技术研究微动疲劳试样的断口表面、微动磨损痕迹、微动磨屑和显微硬度，探索了微动疲劳的失效机制。实验结果表明，在62.5MPa的接触压力下，微动疲劳极限（42MPa）显著降低至约为普通疲劳极限（89MPa）的47%。此外，微动疲劳寿命随着交变应力和接触压力的增加而降低。检查结果表明，接触界面上氧化辅助磨损引起的应力集中导致了微动条件下裂纹的更早萌生和扩展。
