本研究針對純鋁及在商業用高強度鋁合金在陽極製程中所面臨到的技術問題並加以討論。其研究利用高純度純鋁與商用1050純鋁板來討論陽極處理時陽極氧化層之生長行為。探討陽極處理過程中，電解液解離形成的陰離子在陽極膜中的反應。討論所反應氣體對於陽極膜的組成與孔洞的影響。鋁合金基地中的介在物顆粒與二次析出相顆粒對於陽極膜的性質有顯著的影響。研究中亦使用Al-Mg-Si與Al-Zn-Mg-Cu鋁合金討論其顆粒對於陽極膜的影響。在實驗過程中加入輥軋製程(包含冷輥軋與超冷輥軋)，其目的在於改變其介在物顆粒與二次析出相顆粒之數量與形態，並提供適合的工序確保陽極膜的防蝕性質。 純鋁與AA1050商用純鋁在硫酸中並控制不同的陽極條件，觀察及記錄陽極過程中試片表面的氣泡反應過程。利用水下麥克風紀錄陽極處理時的水下訊號，實驗中使用純鋁與AA1050相互對照可推論陽極處理時所反應形成的氣體，根據此差異推論不同材料下所生成的氣體對於陽極膜孔洞率與陽極膜生長的特性。相關的化學反應以及反應是亦會在研究中彙整並加以討論。純鋁材在陽極時，陽極膜中的極化SO42-離子在陽極孔通道中釋放O2-並氧化成SO3氣體，形成SO3奈米氣泡。當陽極膜中的SO3氣泡接觸水分子時會還原為硫酸電解液。部分SO42- 離子則會與陽極膜中的Al(OH)3組成相反應成硫酸鋁。AA1050純鋁在陽極處理時，則因基地中介在物顆粒與基地之間的氧化速率以及金屬離子與氧離子之間結合能力的差異而形成氧氣泡。 對於Al-Mg-Si與Al-Zn-Mg-Cu鋁合金的基地中存在的介在物顆粒與析出相顆粒會因輥軋製程而有顯著的差異。Al-Mg-Si鋁合金其化學組成Al-0.6 wt%Mg-0.4 wt%Si所組成，基地中主要強化相為Mg2Si二次相析出顆粒。而Al-Zn-Mg-Cu鋁合金較複雜其化學組成Al-5.4 wt%Zn-2.5 wt%Mg-1.6 wt%Cu所組成，基地中基地中主要強化相為MgZn2二次相析出顆粒以及Al2Cu, Al7Cu2Fe與Al2CuMg等複雜的介金屬化合物。鋁合金基地中存在的顆粒種類包含有介在物顆粒，一次相介金屬顆粒與二次相析出顆粒。介在物顆粒與一次相介金屬顆粒的尺寸與數量以及二次相析出顆粒的型態變化受輥軋製程影響。 輥軋製程、固溶處理、時效處理對的鋁合金基地微結構差異，以及後續陽極處理討論中則根據SEM、EPMA與TEM觀察及電化學動態極化分析等方式進行分析。其結果Mg-Si、Al-Si以及Al-Cu顆粒影響陽極氧化膜的性質較為顯著；冷輥軋製程後的Al-Mg-Si鋁合金，基地中的低角度晶界的數量顯著增加，介在物顆粒數量與Mg2Si二次相析出顆粒尺寸顯著的下降。Al-Zn-Mg-Cu鋁合金經深冷輥軋製程後再進行陽極處理可以顯著提升氧化膜之抗腐蝕能力。 In recent years, aluminum alloys are widely used for making 3C products due to their lightweight, good mechanical properties and superior cosmetic appearance after anodizing. The purpose of this study is to introduce the anodization behavior of high purity aluminum and the qualities of anodized Al-Mg-Si and Al-Zn-Mg-Cu aluminum alloy with different matrix structures. The individual brief are as following: Gas bubbles formed during anodization of aluminum in sulfuric acid solution but no precise computation of bubbles size have been presented and discussed in literatures. In this study, we utilized X-ray photoelectron spectroscopy (XPS) to investigate the constituent phases of anodic alumina oxide that formed in a short anodization time. Amorphous alumina prevailed in the films together with a certain amount of hydrated alumina (Al(OH)3), oxyhydroxide (AlOOH) and alumina sulfate (Al2(SO4)3). A hydrophone was applied to measure the acoustic pressure field in the electrolyte during anodization. Experimental results indicated that acoustic pressure oscillated with appropriate frequency ranging from 50 Hz up to 500 Hz. A power spectrum density function (PSD) and cepstrum was adopted to analyze the signal of sound spectrum. The collapse and rebirth of gas bubbles on the surface of anodic aluminum oxide (AAO) film and/or at the pore bases oscillated the measured acoustic pressure. We found that the size of gas bubbles could range from 8 nm to 16 nm in diameter to corresponding to the detected oscillated frequency 400 to 50 Hz, respectively. A series of reactions occurred during anodization to yield SO3 gas and O2 gas, which collapsed and rebirth during the early-growth of AAO film. This study also intends to investigate the effect of deformation on varying the matrix of 6063 and 7075 alloy and on the quality of anodized aluminum oxide film.The Al-Mg-Si alloy and Al-Zn-Mg-Cu contains about 0.6 %Mg and 0.4%Si and Al- 5.4 wt% Zn- 2.5 wt% Mg- 1.5 wt% Cu are a heat treatable alloy with precipitation hardening. Different degree of deformation would be introduced to simulate the forming process in making parts resulting in varying effects on the precipitation hardening of matrix. The highest dislocation density was observed in the SCRT6 sample which also showed the lowest inclusion particle numbers among the three Al-Mg-Si samples. The sample that has been subject to the cryo-rolling process prior to rolling and heat treatment showed few subgrains and smaller amounts of second phase particles in the matrix than was the case with the other two sets of Al-Zn-Mg-Cu samples. Subsequently, all samples were anodized in a 15 wt % sulfuric acid solution for different time spans to obtain different state of AAO films. The anodized samples were further analyzed and observed with Field emission scanning electron microscope (FE-SEM), Transmission electron microscopy (TEM), Atomic force microscopy (AFM) and Electrochemical impedance spectroscopy (EIS) and potential-dynamic polarization curve (PD-curve) analysis. We determined that the constituent phases in the AAO film were composed of hydrated amorphous alumina, hydrated oxide (Al(OH)3) and oxyhydroxide (AlOOH) phases together with some silicon-containing particles trapped in the films on Al-Mg-Si samples. The matrix of Al-Zn-Mg-Cu alloy contained the disc-like precipitates of Mg2Zn and Al2Cu and dissolved from the matrix during anodizatione and remained tiny air-pockets in the AAO film. In the potential-dynamic polarization test, the silicon-containing particles and tiny air-pockets that existed in the AAO films were found to inversely influence the corrosion resistance of the anodized samples.
