7075-T6鋁合金經微弧氧化處理後之疲勞特性

Fatigue behavior of 7075-T6 aluminum alloy by micro-arc oxidation

杜承洋(Cheng-Yang Tu)

指導教授 ： 邱傳聖

元智大學/工程學院/機械工程學系/碩士(2009年)

摘要

微弧氧化處理技術是一新興的電化學表面處理技術，適合用來處理鋁、鎂、鈦等輕金屬合金。藉著在水溶液中的電弧放電所產生的表面電漿及短暫高溫，對基材表面進行電漿氧化及高溫熔融，使得所形成的覆膜具備極高的硬度與抗蝕性。本實驗主要是探討7075-T6鋁合金經過微弧氧化處理後，顯微結構的變化對疲勞破壞方式的影響。實驗結果顯示經微弧氧化處理後，由於其基材靠近與塗層內部之介面處較易產生應力集中之現象，因而造成疲勞強度之縮減。

關鍵字

7075 ； 微弧氧化處理 ； 應力集中 ； S-N曲線圖

並列摘要

Micro-arc oxidation (MAO) is a new electrochemical surface treatment technology, suitable for treating the aluminum, magnesium, titanium and other light metal alloys. In aqueous solution by the arc discharge plasma generated by the surface and short-term high temperature plasma on the surface of the substrate oxidation and high temperature melting, the film were formed with high hardness and corrosion resistance. The aim of this research was mainly to observe the fatigue behavior and the morphology of fracture surface of 7075-T6 aluminum alloy with and without MAO. Due to the coating into substrate near the interface, which are considered as the notch sites of stress concentration to induce the crack initiation. The fatigue characteristics was inferior to that of original Al 7075 without MAO.

並列關鍵字

7075-T6 ； MAO ； Stress Concentration ； S-N curve

參考文獻

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