利用機械合金法製備Cu-Al2O3複合材料之研究

Preparation of Cu-Al2O3 Composite Material by Mechanical Alloying

陳進忠(Jin-Zhong Chen)

指導教授 ： 徐開鴻

國立臺北科技大學/工程學院/材料科學與工程研究所/碩士(2009年)

摘要

本論文利用機械合金法將純銅粉與氧化鋁粉混合研磨製備成Cu-3wt.%Al2O3氧化物散佈強化（ODS）複合粉末。固定轉速、BPR、溫度等製程參數，以球磨時間為變數，分別以攪磨機以及行星式球磨機對粉末進行研磨，完成後的複合粉末以XRD、SEM及雷射粒度分析儀等分析粉末的形貌、粒度變化並比較其差異性。從XRD分析結果可知在非封閉性環境研磨粉末導致銅粉形成銅氧化物。從繞射峰半高寬值的變化，可了解粉末微結構隨球磨時間增加的變化情況，行星式球磨機雖為非開放式環境，可有效降低銅氧化情況並可得到較細微的複合粉末，但配合SEM分析可得知其混合均勻性並不佳，無法得到均質化的複合粉末。而經攪磨機研磨後的複合粉末粒徑可有效縮小，在轉速600 rpm、BPR 80、溫度30℃及攪磨10 hr時，即可得到均勻性良好的Cu-3wt. %Al2O3氧化物散佈強化複合粉末，之後進行還原熱處理以有效地改善攪磨機研磨粉末時所發生的氧化情況，使銅氧化量降低。
接著以攪磨10小時之複合粉末利用單軸熱壓的方式製成複合材料，並觀察熱壓參數對材料性質的影響。結果顯示熱壓持溫時間對材料影響較低，隨熱壓壓力與溫度之提升，可有效提升材料之密度、硬度、電性等性質，但溫度若過高時反而會使材料硬度降低。透過氫還原處理的複合粉末更利於燒結，材料經熱壓後可得到良好機械性質的銅基複合材料。銅基複合材料中氧化物含量，會影響複合材料的電性與機械性質，隨著銅氧化物含量的降低，可以有效提高材料的密度、硬度及導電度。

關鍵字

複合材料 ； 氧化鋁 ； 機械合金化法 ； 氧化物散佈強化

並列摘要

Pure Cu powder and alumina powder are used for preparing Cu-3wt.%Al2O3 oxide dispersion strengthen（ODS）composite powders through mechanical alloying（MA）method. Fixed rotation speed of ball mill, BPR and temperature, milling time as the variety unit. The evolution of microstructure change and composite powder morphology are analyzed by XRD, SEM, EDS and Laser light scattering particle size analyzer. Cu oxides are formed during Cu powder preparation where open environment. The microstructure of powder changes the milling time with decreases. Uniformly mixed Cu-3wt.%Al2O3 oxide dispersion strengthened composite powder is obtained with BPR 80 at 30℃and rotating speed 600rpm for attrition milling 10hr, then undergoing reduced heat treatment can improve the oxidation and reducing the Cu oxide effectively.
10 hr milled composite powder is then hot pressed of uniaxial to form bulk, and observe how the parameters of hot pressing influence on material. The result shows that the hot pressing time influence on material is relatively small, but the hot pressing pressure and temperature are relatively high, as the hot pressing pressure and temperature increase, the density、hardness and electrical conductivity also increase, but the hardness will decrease when temperature is too high. The composite powder after proceeding hydrogen reduction is more advantageous for sintering and has much better mechanical properties than using unreduced powders and pure copper. The content of oxide also affects the electrical and mechanical properties of Cu base composite material.

並列關鍵字

Composite material ； Al2O3 ； Mechanical Alloying ； Oxide dispersion strengthened

參考文獻

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