退火條件對鋁材陽極處理及電解著色之影響

THE EFFECT OF ANNEALING CONDITIONS ON ANODIC TREATMENT AND ELECTROLYTIC COLORING OF ALUMINUM SHEET

郭賦(Fu Kuo)

指導教授 ： 施幸祥

大同大學/工程學院/化學工程學系所/碩士(2006年)

摘要

本研究在探討退火條件對陽極處理膜及其電解著色膜物性之影響，期望利用退火處理之優點，獲得更良好的氧化鋁膜，以利於進行電解著色，並尋求最佳黑色電解著色操作條件。將退火後之純鋁試片在硫酸溶液中進行陽極處理及在硝酸銀溶液中進行電解著色，藉由微硬度、膜厚及色差的測量，並且配合SEM之觀察及EDS分析存在的化學元素，來瞭解退火之影響。
實驗結果發現，經過一定溫度和時間下退火處理，由於表面結晶組織重新排列，可改善氧化膜的生長情形。在退火後所產生的結晶相，由X-ray繞射分析得知為γ-Al2O3，此外，由SEM可觀察到，退火後之鋁片，其孔洞結構較大，因此所產生的氧化鋁膜會影響在硝酸銀溶液中電解著色。使用色差計測量，可測得最低的L值為10.32，而在可見光波長範圍下測試下，可得最低反射度值為5.54%之黑色陽極氧化膜。
為了在鋁片上得到最佳的黑色膜，其最佳的操作條件如下：退火溫度 500 ℃及退火時間2hr，陽極電流密度 2 A/dm2，浴溫20 ℃。

關鍵字

電解著色，陽極處理，退火

並列摘要

This research is to investigate the effect of the annealing conditions on the physical properties of the anodic oxide film and colored film. It is expected that by taking the advantages of annealing, a better aluminum oxide layer can be obtained to proceed the electrolytic coloring for getting a black film. By the way, to find the optimum operation conditions to obtain the darkest shade of black anodic film on aluminum. Specimen of the annealed aluminum was investigated after anodizing in sulfuric acid solution and then electrolytic coloring in silver nitrate solution. The microstructure, microhardness, thickness, chromatism and chemistry elements of anodic oxide film were studied by using scanning electron microscopy (SEM), microhardness tester, electronic thickness tester, spectrophotometer and energy dispersive spectroscopy (EDS).
It is found that after the annealing treatment at given temperature and time, because of the rearrangement of the surface crystalline structure, the growth condition of the anodic film can be improved. From the analysis of X-ray diffraction and the observation of SEM, it is known that the crystalline produced after the annealing is γ-Al2O3, and the structures of the pores are larger. Therefore, the anodic oxide film from annealing would be helpful for the electrolytic coloring in the silver nitrate solution, hence the lowest L-value of 10.32 and the minimum reflectivity of 5.54 % were obtained.
To obtain the better black film on aluminum, the best operating conditions are as follows: annealing temperature of 500 ℃ for 2hr, anodic current density of 2 A/dm2 at bath temperature of 20 ℃.

並列關鍵字

electrolytic coloring ； anodic treatmemt ； annealing

參考文獻

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