Analysis of fatigue damage of aluminium alloy under multiaxial random vibration
Analysis of fatigue damage of aluminium alloy under multiaxial random vibration
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多轴随机振动下铝合金疲劳损伤分析
DOI：
10.1016/j.prostr.2018.12.087
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发表时间：
2018
期刊：
影响因子：
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通讯作者：
Tadahiro Shibutani
中科院分区：
文献类型：
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作者：
Junji Sakamoto;Tadahiro Shibutani
许多研究都对材料在振动作用下的疲劳损伤进行了研究。然而，振动引起的疲劳损伤机理尚不清楚，也没有建立振动疲劳强度的评估方法。因此，建立一种材料振动疲劳强度的评价方法，对于保证材料在设计中具有合适的强度是非常重要的。在本研究中，我们对材料在多轴随机振动作用下的断裂机理进行了实验研究。我们选择了A5056铝合金作为试验材料，并采用了带缺口的扣头式试件。在10-5000 Hz的频率范围内，在不同的加速度输入(10、20、30、40、50、60和70 GRMS)下进行了多轴随机振动实验。在振动测试期间，我们对振动行为进行了观察。振动试验后，用扫描电子显微镜观察了试件的断口。结果表明，对于给定形状和尺寸的试件，疲劳断裂是由于弯曲共振模式所致。此外，裂纹在断口表面的不同区域萌生，随后扩展；随后，裂纹聚合。最后，讨论了有限元分析能否预测材料在振动作用下的疲劳寿命。
Many studies have investigated the fatigue damage of materials under vibration. However, the mechanism of vibration-induced fatigue damage remains unclear, and no method has been established for evaluating the vibration fatigue strength. Therefore, it is important to establish an evaluation method for the vibration fatigue strength of materials to ensure appropriate strength in their design. In this study, we performed experiments to investigate the fracture mechanism of a material under multi-axial random vibration. We selected aluminium alloy A5056 as the test material and employed button-head-type specimens with a notch. The multi-axial random vibration experiments were performed at different acceleration inputs (10, 20, 30, 40, 50, 60, and 70 Grms) within a frequency band of 10–5000 Hz. During the vibration tests, we conducted observations of vibration behaviour. After the vibration tests, we observed the fracture surfaces of the specimens using a scanning electron microscope. The results show that the fatigue fracture was due to the bending resonance mode for the given shape and dimensions of the specimens used in this study. In addition, cracks initiated at different areas on the fracture surface and later propagated; subsequently, the cracks coalesced. Finally, we discussed whether the fatigue life of materials subjected to vibration can be predicted using finite element analysis.