Microstructure and mechanical properties of the cast and wrought Al–Mg–Si alloy micro-alloyed with 0.04 wt% and 0.08 wt% Sn were investigated at various processing conditions, viz. as-cast, solutionised, homogenised, hot rolled and peak-aged. Additionally, fracture surfaces of the alloys were also examined in the as-cast, peak-aged cast and peak-aged rolled conditions. It was observed that 0.04 wt% Sn favours the formation of a lamella-like eutectic Al + Mg₂Si, whereas 0.08 wt% Sn favours the formation of plate/rod-like Mg₂Si. The formation of the former deteriorated the hardness and tensile strength, but improves the ductility, whereas the formation of the later was found to contribute to the hardness, tensile strength as well as ductility of the Al–Mg–Si alloy. Homogenisation treatment had reduced the hardness of all the alloys to the lowest value due to the dissolution and spheroidisation of the intermetallic phases. However, hot rolling had significantly increased the hardness, tensile strength and ductility of the alloys. Thus, the increase in hardness, tensile strength and ductility were more prominent in the peak-aged rolled alloys relative to the peak-aged cast alloys. At the studied processing stages, the hardness and tensile strength of Al–Mg–Si alloy were found to decrease with the addition of 0.04 wt% Sn and increase with the addition of 0.08 wt% Sn. However, the ductility increased with Sn addition, and the increment was more prominent when micro-alloyed with 0.04 wt% Sn. Improvement in ductility in 0.04 wt% Sn alloy could be attributed to the formation of script-like Al(Fe, Mn)Si phase, whereas in 0.08 wt% Sn alloy could be attributed to the formation of ductile Mg₂(Si, Sn) phase. Furthermore, the fractography study had revealed that the fracture in the alloys was mainly developed by the cracking of Al(Fe, Mn)Si intermetallic particles. The fractures mode in the as-cast and peak-aged cast alloys was mainly by transgranular brittle with a cleavage fracture surface, whereas in the peak-aged rolled alloys was mainly by transgranular ductile with a dimpled fracture surface.

在不同的加工条件下研究了铸造和锻造 Al-Mg-Si 合金微合金化与 0.04 wt% 和 0.08 wt% Sn 的显微组织和机械性能，即。铸态、固溶、均质、热轧和峰时效。此外，还在铸态、峰时效铸造和峰时效轧制条件下检查合金的断裂表面。据观察，0.04 wt% Sn 有利于形成片状共晶 Al + Mg ₂ Si，而 0.08 wt% Sn 有利于形成板/棒状 Mg ₂西。前者的形成降低了硬度和抗拉强度，但提高了延展性，而后者的形成有助于提高 Al-Mg-Si 合金的硬度、抗拉强度和延展性。由于金属间相的溶解和球化，均质化处理将所有合金的硬度降低到最低值。然而，热轧显着提高了合金的硬度、抗拉强度和延展性。因此，与峰时效铸造合金相比，峰时效轧制合金的硬度、抗拉强度和延展性的增加更为显着。在研究的加工阶段，发现 Al-Mg-Si 合金的硬度和抗拉强度随着 0.04 wt% Sn 的添加而降低，并随着 0.08 wt% Sn 的添加而增加。然而，延展性随着 Sn 的加入而增加，并且在加入 0.04 wt% Sn 的微合金化时增加更为显着。0.04 wt% Sn 合金延展性的提高可归因于脚本状 Al(Fe, Mn)Si 相的形成，而在 0.08 wt% Sn 合金中，可归因于延展性 Mg 的形成₂ (Si, Sn) 相。此外，断口分析表明，合金的断裂主要是由 Al(Fe, Mn)Si 金属间化合物颗粒的开裂造成的。铸态和峰时效铸造合金的断裂模式主要是具有解理断面的穿晶脆性，而峰时效轧制合金的断裂模式主要是具有凹痕断面的穿晶韧性。