電參數及電解液對陽極氧化鋁之孔洞結構形貌與性質之影響研究

A Study of Electrical Parameter and Electrolyte Effect on the Cell Structure, Microstructure and Properties of Anodized Aluminum Oxide

高嘉駿(Chia-Chun Kao)

指導教授 ： 林新智

國立臺灣大學/工學院/材料科學與工程學研究所/碩士(2020年)

https://doi.org/10.6342/NTU202001966

摘要

陽極處理作為鋁合金的表面改質技術已經被使用了將近一個世紀之久，但近年來奈米材料的新起，使這個傳統的技術有了新的應用。透過適當的參數控制，陽極處理所生成的陽極氧化鋁(Anodic Aluminum Oxide, AAO)可以具有奈米尺度的高規則排列六角形孔洞陣列結構，可應用在感測器、催化劑或模具的使用上，深具發展潛力。
本研究透過調整陽極處理製程中直流電下陽極電流密度和工作時間、不同條件的電解液及脈衝電流下負電流密度和頻率，在純鋁上探討不同參數對陽極氧化鋁的孔洞結構與性質的影響。以掃描式電子顯微鏡、X光繞射儀進行膜層微觀結構與成分分析；以維氏硬度機分析膜層機械性質；以動電位極化曲線分析膜層的耐腐蝕性質；以Ball-on-Disc磨耗試驗評估膜層的耐磨耗性質。
研究結果指出，陽極電流密度主要影響陽極處理膜層生長速率，電流密度過大會造成膜層缺陷產生；工作時間和膜層厚度成正比；電解液的溫度影響陽極氧化鋁的孔洞直徑大小和膜層硬度；不同的電解液系統則因為導電性不同而可以得到不同尺度的陽極氧化鋁孔洞直徑區間，可以依需求選用適當的電解液系統或是依所需比例混合不同的電解液；負電流密度會使陽極處理試片上產生氫氣泡，破壞陽極氧化鋁的孔洞結構；頻率則對陽極氧化鋁的結構或性質沒有太大的影響。

關鍵字

純鋁 ； 陽極處理 ； 奈米材料 ； AAO

並列摘要

Anodizing has been used as a surface treatment of aluminum for almost a century. But the rapidly increasing interest in nanoscale materials has propelled this traditional technology to the fore. With proper controlled parameters, Anodic aluminum oxide (AAO) can have nanoscale, highly self-ordering hexagonal pore structure which can be applied on sensors, catalysis and templating.
In this study, several anodizing parameters including positive current density, time, different electrolyte condition, negative current density and frequency are controlled to discuss the influence of these parameters on AAO pore structure and properties. The microstructure and composition of the films are analyzed by Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD). Mechanical property is evaluated by Vickers Hardness Test. Potentiodynamic polarization test is used for analyzing corrosion behavior and Ball-on-disc tribometer for wear resistance performance.
Experimental results point out that positive current density mainly effect the aluminum oxide growth rate. Over high current density may cause defect appear. Time is proportional to the film thickness. The temperature of electrolyte effects the AAO pore diameter and films hardness. Different pore size interval can be obtained by different electrolyte system and concentration due to the conductivity difference. Negative current density may cause the generation of hydrogen on the sample surface which destroyed the AAO pore structure. Frequency doesn’t have significant effect on AAO pore structure or properties.

並列關鍵字

pure aluminum ； anodizing ； nano-material ； AAO

參考文獻

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