In this work, the microstructure of Al-Mg-Si-Cu alloy was tailored by controlling the aging process and its effect on the fracture mechanism was systematically explored by in-situ tensile test and microstructural observations. It was found that the aging process influences the mechanical performance and leads to the alteration of the tensile fracture mode of the aged alloy. Microscopy observations revealed that the Al₂Cu precipitates distribute heterogeneously in the peak-aged alloy. The density of the Al₂Cu precipitates in the intergranular fracture regions is much higher than that in the transgranular regions. The effect of Al₂Cu precipitates on the fracture mode was systematically discussed and a hybrid fracture mechanism was proposed.

在这项工作中，通过控制时效过程来定制Al-Mg-Si-Cu合金的显微组织，并通过原位拉伸试验和显微组织观察系统地探讨了其对断裂机理的影响。发现时效过程会影响机械性能，并导致时效合金的拉伸断裂模式发生变化。显微镜观察表明，Al ₂ Cu沉淀在峰时效合金中分布不均。Al ₂ Cu析出物在晶间断裂区的密度远高于在晶间断裂区。系统地讨论了Al ₂ Cu析出物对断裂模式的影响，并提出了混合断裂机理。