不同陽極處理對7075-T6及7050-T6鋁合金耐腐蝕性質及疲勞強度分析

邱奕緯(Yi-wei Chiu)

指導教授 ： 施登士

國立中央大學/工學院/機械工程學系/碩士(2015年)

摘要

本研究對7075-T6及7050-T6兩種材料進行三種不同的陽極處理，分別是一般陽極、低定電流硬化陽極和高定電流硬化陽極，陽極氧化膜的厚度皆控制在10um左右。封孔處理後對材料進行腐蝕測試，並記錄各材料的腐蝕電位(Ecor)及腐蝕速率(Icor)。利用光電子能譜儀(XPS)分析陽極皮膜的表面層和介面層(氧化膜/基材)組成分，電子顯微鏡(SEM)觀察氧化膜表面型態，探討其結果與耐蝕能力之關係。
各材料皆會加工成試棒以進行旋轉梁疲勞試驗，並記錄其疲勞曲線。陽極後的材料會分成內外兩部分進行氫含量測試。最後，利用材料中之氫含量分布及材料表面之陽極氧化膜探討對材料疲勞強度之影響。
實驗結果顯示，陽極氧化鋁孔洞大小、間距以及形態都影響著腐蝕性質。疲勞強度則與陽極氧化膜品質以及材料內部之氫含量有關。

關鍵字

7075-T6 ； 7050-T6 ； 陽極處理 ； 光電子能譜儀XPS ； 陽極極化曲線 ； 旋轉梁疲勞試驗

並列摘要

In this study, Al7075 and Al7050 alloy samples were prepared for three Anodization treatment(Anodization、Hard Anodization(low current density)、Hard Anodization(high current density) ) to obtain a fixed anodic aluminum oxide (AAO) film thickness(10um).
The anodized and sealed samples were observed and analyzed by X-ray Photoelectron(XPS) , Scanning electron microscope(SEM),hydrogen concentration detector and potentiodynamic test.The samples were also carrying out rotating bending fatigue test.
We found the factors influenced the corrosion resistance of two alloy samples included pore numbers and/or volume,constituted oxide phases and voids formed in the AAO film.And the anodized/sealed Al7050 alloy samples exhibited the greatest fatigue strength at 107 life cycles among all samples. Hydrogen content remained in the samples’ matrix mainly

參考文獻

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