6082鋁合金具有質輕、高比強度、耐蝕性佳等優點，目前已廣泛應用在交通工具與建築材料上。此合金為熱處理型，熱處理條件對於其機械性質會有很大的影響。與鋼鐵材料相比之下，加工成形性不佳的問題導致其在應用受到限制。一般而言，鋁合金可藉由施加熱處理改善成形性。因此，本實驗利用不同溫度之熱處理，探討其對6082鋁合金拉伸性質之影響，另外也進行常溫到500℃之拉伸試驗以了解在不同溫度加工時此材料之變形行為。
本研究選用兩種熱處理方式：一種為退火處理(O材)，退火溫度為415℃，時間3小時之後空冷；另一種為固溶處理(T4NA材)，固溶溫度為570℃，持溫時間為2小時後水冷，並放置自然時效24小時後與O材進行相同之拉伸測試。
實驗結果發現，兩組材料內Al(Fe,Mn,Cr)Si相在拉伸溫度RT至500℃皆與裂紋起始有關，O材內的Si顆粒也會造成裂紋的產生。在RT 及 100℃時，O材之拉伸曲線會有DSA產生，推測DSA與O材基地內第二相含量是拉伸溫度RT至200℃區間影響延伸率的因素。拉伸溫度300℃及400℃時，O材及T4NA材之UE陡降推測是因動態回復及動態再結晶導致加工硬化率降低所造成；拉伸溫度400℃時O材因為受Si顆粒破裂影響而造成總伸長量較低。拉伸溫度400℃及 500℃時，兩組材料之曲線皆有抖動的現象，觀察拉伸試片平行部表面發現晶粒有相對位移的變形特徵，與文獻對比得知上述情況是起因於動態再結晶。拉伸溫度500℃觀察到晶格狀裂紋，此裂紋可能為晶界在拉伸時產生熔融所造成，透過適度的熔融可調節變形，有助於緩和動態再結晶所造成均勻延伸率下降的現象並使延性提升。
關鍵字：固溶處理;高溫拉伸

6082 is an important aluminum alloy for automotive industry because of its low cost, good weldability, high strength to weight ratio and good corrosion resistance. To increase ductility for broadening applications of this alloy, annealing has been wildly used in industry, but it takes much time in process. For this reason, we use solution treatment to improve it. This research is to investigate tensile properties of 6082 aluminum alloy with solution treatment and with annealing. The result shows that uniform elongation of solution treatment sample(T4NA) is higher than annealing sample(O) at room temperature. It could be observed DSA effect on O at tensile temperature RT and 100℃. T4NA had a tendency to DRX at 300℃, and O was at 400℃. At tensile temperature 500℃, the growth of new grains due to DRX can be observed easily on fracture surface of O and T4NA.

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