- 期刊
壓鑄用ADC12鋁合金之硬脆相改良
Refinement of the Brittle Phases in ADC12 Die Casting Al Alloy
摘要
壓鑄用ADC12鋁合金之鑄造性良好，應用十分廣泛，但一般壓鑄件通常不作T6處理來提升拉伸性質(因在高溫固溶處理時易發生表面起泡問題)，故其製品往往只能作為外觀件，若作為結構件則常有延性不足之問題。本研究以成分微調方式來進行改善，共配製七種ADC12系列鋁合金，包括ADC12(10Si)、ADC12(11Si)兩種商用鋁合金以及ADC12-1~ADC12-5等五種改良型合金，來提升壓鑄用ADC12鋁合金之拉伸性質。實驗結果顯示，七種ADC12系列鋁合金中，添加0.02%Sr、0.3%Cr及0.3%Zr之ADC12-2鋁合金顯現最佳之微觀組織與拉伸性質。所添加微量Sr調質劑可將合金內片狀共晶矽轉化為微細纖維狀，Cr中和劑將大片狀β-Al_5FeSi富鐵相轉化為細小塊狀之α-Al_(13)(Fe,Cr)_4Si_4，使合金之延伸率得以提升。拉伸性質數據顯示，在壓鑄鑄造狀態下改良型之ADC12-2鋁合金降伏強度、抗拉強度、延伸率及品質指數分別為259MPa、345MPa、3.9%及434MPa；若與商用ADC12鋁合金者作比較，改良型ADC12-2鋁合金之延伸率與商用ADC12鋁合金者相近，但降伏強度及抗拉強度均明顯優於商用ADC12鋁合金。
並列摘要
Due to its excellent castability the ADC12 die casting Al alloy is widely used for various consumer products. However, its applications as structural components are limited due to its poor mechanical properties, especially in ductility. Normally, the T6 treatment is seldom applied to the die casting components for improvement of their mechanical properties, since blistering problem may easily occur during solution treatment. As such, a study aims to improve its mechanical properties is conducted. A total of seven ADC12-type alloys were studied, including two commercial ADC12 alloys with different Si contents and five modified ADC12 alloys, namely ADC12(10 Si), ADC12(11 Si) and ADC12-1 ~ ADC12-5. The results showed that, among the various modified ADC12-type alloys examined, the ADC12-2 alloy with additions of 0.02% Sr, 0.3% Cr and 0.3% Zr exhibits proper microstructures in the as cast condition with promising mechanical properties. The Sr modifier and Cr neutralizer added to the alloy have modified the shapes of coarse plate-like eutectic Si into fibrous and the thin sheet-like β-Al_5FeSi into small particles of α-Al_(13)(Fe,Cr)_4Si_4, respectively. Tensile properties data show that the yield strength, tensile strength, elongation and quality index of the as-cast ADC12-2 alloy to be 259MPa, 345MPa, 3.9% and 434MPa, respectively. In comparison with the commercial ADC12(10 Si) alloy, the tensile elongation of ADC12-2 alloy is similar to that of ADC12(10 Si), but the yield strength and tensile strength are significantly higher than those of ADC12(10 Si) alloy.