7A04铝合金壳体失效分析

Failure analysis of 7A04 aluminum alloy shell

7A04铝合金壳体在使用过程中发生开裂失效,通过对失效件的外观、断口宏微观形貌观察,以及对失效件和库存件材质、显微组织、力学性能和表面应力等方面的测试,对壳体的开裂原因进行了分析。结果表明,失效壳体为沿纵向脆性断裂,壳体横向力学性能较低,使用过程中承受较大的工作应力是导致开裂的主要原因。

Cracking failure occurred in 7A04 aluminum alloy shell during service.The causes of cracking were analyzed by observing the appearance of failed part and macro and micro morphologies of fracture,testing and comparing the material,microstructure,mechanical properties and surface stress of failed parts and inventory parts.The results show that the failed shell is brittle fractured along longitudinal direction of the shell,the main cause of the cracking is that the transverse mechanical properties of the shell is relatively low,and the working stress beared by the shell is large.