6XXX系鋁合金發展歷史悠久，運用範圍廣泛，為熱處理型的析出強化材，具有質輕、成形性佳、高比強度、耐蝕性佳等優點，常使用於交通運輸工具上，如：汽車、船隻、航太等工業，另外也常使用於建築業上。此系合金主要析出強化相為Mg2Si，而熱處理條件對其機械性質會有很大的影響，本實驗施以固溶處理+人工時效處理 (T6)的熱處理條件。較高的固溶溫度會有較大的固溶量但卻有第二相重融的問題產生，因此本實驗探討6066及6067鋁合金經兩種固溶溫度後T6材之拉伸性質表現；此外，材料穩定性在應用上也是非常重要的性質，因此本實驗也利用韋柏解析評估材料的可靠度。
實驗結果顯示，6066鋁合金經520℃固溶處理後T6材拉伸強度較經550℃固溶處理後T6材的拉伸強度高出約100MPa，造成此種可觀差異的原因推測為經550℃固溶處理時，Q相熔融凝固過程中，在6066鋁合金內部留下的微孔洞使其有效截面積減少所致；然而6067鋁合金經520℃固溶處理後T6材拉伸強度反而較經550℃固溶處理後T6材的拉伸強度低，兩者差異約為50MPa，這可能是因為經550℃固溶處理後，材料內部有較高的析出物密度所致。延性方面，6066及6067鋁合金經550℃固溶處理後T6材均展現較優異的延性。對此，本實驗在結果與討論中利用6067-HCu鋁合金驗證Q相對材料在經不同固溶處理溫度後T6材拉伸性質之影響。
材料可靠度方面，本實驗針對經550℃固溶處理後T6材拉伸性質中的降伏強度 (YS)與總延伸率 (TE)作韋伯解析。結果顯示，不論是YS或TE，6066鋁合金都接近隨機破壞的型式，其可靠度不佳，推測是因上述Q相造成的微孔洞所致；而6067鋁合金為破壞率遞增型，其可靠度優於6066鋁合金。另外，本實驗在結果與討論中利用6067-HCr鋁合金進行韋伯解析，用以驗證材料內部硬質相對可靠度的影響。

6xxx-series aluminum alloys are age hardening alloys which have many excellent properties, such as light weight, good formability, high specific strength and good resistance to corrosion. They are widely used in transportation applications, for instance, automobiles, aircraft industry, and architectures as well. The main precipitation phase of the series is Mg2Si and the conditions of heat treatment will have a great impact on the mechanical properties. In this study, we apply solid solution treatment and then use the artificial aging treatment (T6). The higher temperature of solid solution will have larger amount of solid solution, but it will also lead to the problem of remelting second phase. Therefore, the tensile properties of T6 treatment 6066 and 6067 aluminum alloys taking two different solid solution temperatures will be discussed. In addition, reliability is an important property and it will be estimated by Weibull analysis.
According to the tensile testing, T6 treatment 6066 aluminum at solid solution temperature of 520℃ has higher strength than that at solid solution temperature of 550℃ by 100MPa. This may caused by the Q phase which left the tiny voids in alloy when 6066 aluminum took solid solution temperature of 550℃. However, 6067 aluminum may have the opposite condition. It has higher strength under solid solution temperature of 520℃. This was probably due to the higher precipitates density. On the other hand, both two alloys have good ductility when taking solid solution temperature of 550℃. In this study, 6067-HCu aluminum was used to verify the Q phase effect in chapter 5.
In terms of reliability, this study used Weibull analysis to estimate the YS and TE properties which took solid solution temperature of 550℃. Observation indicated that for both YS and TE, 6066 aluminum has a constant failure rate, and it may be due to the Q phase. However, 6067 aluminum has an increasing failure rate, and it has better reliability than 6066 aluminum. Furthermore, 6067-HCr aluminum was used to verify the effect of hard phases on reliability in chapter 5.

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