Abstract A detailed analysis of grain boundaries in a highly textured Al-Mg-Si-Cu alloy is presented in this work. Electron backscatter diffraction demonstrates the presence of three main categories of grain boundaries in addition to sub-grain boundaries. These grain boundaries have been systematically analysed using high–resolution scanning transmission electron microscopy. Intergranular corrosion (IGC) susceptibility was statistically correlated with the same defined grain boundaries. A high density of metastable Q′-phase grain boundary particles correlates with a reduction in Cu segregation at grain boundaries and increased IGC resistance. Results herein are relevant in further understanding grain boundary structures in Al-Mg-Si-Cu alloys and their susceptibility to IGC, and can be implemented into modelling frameworks.

中文翻译：

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挤压Al-mg-Si-cu合金的晶界结构及其与晶间腐蚀的相关性

摘要 本文详细分析了高织构的 Al-Mg-Si-Cu 合金中的晶界。电子背散射衍射证明除了亚晶界之外还存在三个主要类别的晶界。已使用高分辨率扫描透射电子显微镜系统地分析了这些晶界。晶间腐蚀 (IGC) 敏感性与相同定义的晶界在统计上相关。亚稳态 Q' 相晶界颗粒的高密度与晶界处 Cu 偏析的减少和 IGC 电阻的增加有关。本文的结果与进一步了解 Al-Mg-Si-Cu 合金中的晶界结构及其对 IGC 的敏感性相关，并且可以实施到建模框架中。