The Fe-rich intermetallic phases have a broadly detrimental effect on the mechanical properties of Al–Cu alloy. In this paper, the continuous evolution of Fe-rich intermetallics and their effects on mechanical properties, especially the tensile fracture behavior of 2219 wrought Al–Cu alloys as a function of Fe content against different processing approaches (i.e., as-cast, homogenization, multidirectional forging, and solution-peak aging treatment) were investigated using optical microscopy, scanning electron microscopy, and tensile tests. The results indicated that needle-like Al₇Cu₂Fe or Al₇Cu₂(Fe, Mn) intermetallics mainly presented in the final microstructures of all alloys with various Fe contents. The size and number of Al₇Cu₂Fe/Al₇Cu₂(Fe, Mn) intermetallics increased with the increase of Fe content. The increase of Fe content had little influence on the ultimate tensile strength and yield strength, while obvious deterioration in the elongation, because fracture initiators mainly occurred at the Al₇Cu₂Fe/Al₇Cu₂(Fe, Mn) particles or particles–matrix interface. Therefore, the 2219 Al–Cu alloy with 0.2 wt.% Fe content presented relatively low tensile ductility. The tensile fracture mechanism has been discussed in detail.

中文翻译：

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2219不同铁杂质含量的锻造Al-Cu合金的组织和拉伸断裂行为

富铁金属间相对Al-Cu合金的机械性能具有广泛的不利影响。在本文中，富铁金属间化合物的不断演变及其对机械性能的影响，特别是2219变形Al-Cu合金的拉伸断裂行为，随不同处理方法（如铸态，均质化，使用光学显微镜，扫描电子显微镜和拉伸试验研究了多向锻造和固溶时效处理。结果表明，针状的Al ₇ Cu ₂ Fe或Al ₇ Cu ₂（Fe，Mn）金属间化合物主要存在于所有不同Fe含量的合金的最终组织中。Al的大小和数量₇ Cu ₂ Fe / Al ₇ Cu ₂（Fe，Mn）金属间化合物随着Fe含量的增加而增加。Fe含量的增加对极限抗拉强度和屈服强度影响很小，而伸长率则明显降低，这是因为断裂引发剂主要发生在Al ₇ Cu ₂ Fe / Al ₇ Cu ₂（Fe，Mn）颗粒或颗粒上。矩阵接口。因此，铁含量为0.2 wt。％的2219 Al-Cu合金具有较低的拉伸延展性。已经详细讨论了拉伸断裂机理。