本研究針對Al-Mg-Si 6061鋁合金添加微量元素Cr、Mn進行探討，所設計之三種合金6061、6061+Cr及6061+Mn鋁合金藉由熔煉爐鑄造，一批以550˚C/24h、爐冷的方式進行均質化處理，另外一批不均質化處理。這兩批分別進行450˚C熱鍛、鍛壓量70%再作T6熱處理（固溶520˚C/2h，時效167 ˚C/24h）。探討不同微量元素添加及T6處理後的機械性質以及顯微組織。實驗結果顯示，6061、6061+Cr及6061+Mn鋁合金經由T6處理後硬度皆有明顯的提升，而強度方面在添加Cr 0.3%及Mn 0.7%時有最大值。而且已均質化之合金其強度皆小於未作均質化之合金。The effects of trace elements chromium (Cr) and manganese (Mn) addition on aluminum-magnesium-silicon alloys were investigated. The alloys of interest are AA6061. Alloys design of the casted 6061, 6061+Cr and 6061+Mn aluminum alloys by melting furnace. The alloys were homogenizated at 550˚C for 24hrs and furnace cooling. After hot forging process, the alloys were solid solution treated at 520˚C for 2 hrs and then aged at 167˚C for 24hrs; Mechanical properties test results are reports. Moreover, the morphologies of casted and T6-heat treated after hot forging were observed by optics microscope (OM).Results indicated that after T6 treatment, the hardness of 6061, 6061+Cr and 6061+Mn aluminum alloys increase obviously. 6061-Cr0.3% has a maximum strength among 6061-Cr x wt% (x=0.1, 0.3, 0.4, 0.5). 6061-Mn 0.7% has a maximum strength among 6061-Mn y wt% (y=0.1, 0.2, 0.5, 0.7, 0.9, 1.1). The strength of homogenized alloys are lower than non-homogenized alloys.
