7A04铝合金球铰在疲劳试验过程中发生断裂失效.通过对失效件断口的宏微观形貌观察、能谱分析以及有限元模拟计算等,分析了 7A04铝合金球铰疲劳裂纹形成原因及其失效机制.结果表明,疲劳裂纹萌生于气孔、氧化夹杂物等冶金缺陷位置,并在后续起桥接连通作用进一步加速裂纹扩展,造成试件断裂失效.
The fracture failure of 7 A04 aluminum alloy spherical hinge occurred during the fatigue test.Through the macro and micro morphology observation,energy spectrum analysis and finite element simulation calculation of the fracture of the failure part,the causes of fa-tigue crack formation and failure mechanism of the spherical hinge were analyzed.The re-sults show that the fatigue crack initiates at the location of metallurgical defects such as pores and oxide inclusions,and further accelerates the crack propagation in the subsequent bridg-ing connection,resulting in fracture failure of the specimen.