鎂鋰合金添加微量元素之微弧陽極處理研究

Micro-arc anodizing of magnesium-lithium alloys add rare-earth element

高銘辰(Vincent Kao)

指導教授 ： 李雄

國立中央大學/工學院/機械工程學系/碩士(2008年)

摘要

本研究利用微弧陽極處理的方式改善鎂鋰合金系列LAZ1110、LAZ1110+Be、LAZ1110+Sc、LAZ1110+Be+Sc之耐蝕性，並探討其差異性，實驗中利用矽酸鈉(40g/L)、氫氧化鈉(100g/L)、次磷酸鈉(20g/L)、乙二酸(80g/L)之電解液進行陽極處理，然後針對不同材料與時間參數進行探討，由實驗結果顯示，LAZ1110、 LAZ1110+Be、LAZ1110+Sc、LAZ1110+Be+Sc其四種材料所添加之微量元素，其中添加Be元素之LAZ1110+Be為其四種材料中其抗蝕性最差的，而添加Sc元素之LAZ1110+Sc為其四種材料中其抗蝕性最佳的，乃由於添加Be元素具有減少熔融金屬表面的氧化作用，並有阻燃的效果，造成LAZ1110+Be於陽極處理的過程中破壞陽極膜的生成，而Sc原素本身既有增加抗蝕的效果，故LAZ1110+Sc為其四種材料中其抗蝕性最佳的。
陽極膜會因操作溫度、頻率、時間、電流密度、陽極處理液濃度等參數的影響，使陽極膜有不同結構與抗蝕性，本實驗乃利用相同電流密度，相同操作條件，利用不同時間參數找出陽極處理最佳操作條件，實驗結果顯示於8min的操作條件下，陽極膜其抗蝕性為最佳。

關鍵字

微弧陽極處理 ； 鎂鋰合金

並列摘要

This research tries to improve corrosion resistance of LAZ1110, LAZ1110 +Be, LAZ1110 +Sc, LAZ1110 +Be +Sc magnesium alloys by means of micro-arc anodizing. In the experiment, the electrolytic solution is composed of 40gl-1 Na2SiO3, 100gl-1 NaOH, 20gl-1 NaPO2and 80gl-1(COOH)2.2H2O in distilled water. After the micro-arc anodizing treatment, it will discuss to various parameters.
The results indicated that the anodic oxidation film has better corrosion performance under the pulse current condition. In four materials of LAZ1110, LAZ1110 +Be, LAZ1110 +Sc, LAZ1110 +Be +Sc magnesium alloys, LAZ1110 +Be have the worst of corrosion resistance, and LAZ1110 +Sc have the best of corrosion resistance, in the basic extrapolate, add the Be element have decrease the oxidation on the magnesium alloys surface, this phenomenon destroy the anodic oxidation film of LAZ1110 +Be during micro-arc anodizing treatment, add the Sc element have increase the effect of corrosion resistance.
Temperature, frequency, time, current density, duty cycle and electrolytic concentration have an influence on micro-structure and corrosion performance of anodic films. In our research, it fixed current density and another parameter, and it used various of time parameter to find out the best operate condition, the results indicated that at 8min of operate condition of micro-arc anodizing treatment have the best of anodic oxidation film.

並列關鍵字

magnesium-lithium alloys ； anodizing

參考文獻

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