利用機械合金化法製備銅基複合材料之研究

Processing of Cu-matrix Composite by Mechanical Alloying

郭書凱(Shu-kai Kuo)

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(2008年)

摘要

本實驗是將單一原始粉末Cu-10wt％Al合金粉，在大氣的環境下，利用機械合金化法製備成氧化物散佈強化（ODS）複合粉。固定轉速、BPR（Ball-to-powder ratio）、溫度等製程參數，改變攪磨的時間，從0hr ~ 40hr 每4小時為一單位，再以XRD、SEM、EDS、TEM及雷射粒度分析儀，分析粉末的相成分變化與型貌。從XRD分析結果中繞射峰值的偏移與晶格常數的變化，可了解富鋁相在銅晶格中的析出，配合SEM分析可觀察析出的富鋁相所形成第二相的散佈情形，經過EDS與TEM的分析可以確認散佈相為鋁氧化合物。在轉速600 rpm、BPR 80、溫度30℃及攪磨24hr時，可得到均勻性良好與奈米尺度的銅基氧化物散佈強化複合粉。
接著將攪磨24小時之複合粉，利用單軸熱壓的方式製成複合材料。經950℃持溫30分鐘與65MPa的熱壓壓力後，可得到緻密性為92％的銅基複合材料。且銅基複合材料硬度值比純銅高出許多，顯示氧化鋁的均勻散佈能有效阻礙差排的滑移，提升其機械性質。銅基複合材料中氧化鋁含量，會影響複合材料的電性與機械性質，隨著氧化鋁含量的增加，硬度有提高的趨勢，但抗彎強度及導電度則會降低。而經20%以下的熱加工量後，由於氧化鋁含量過高，使複合材料整體可塑性降低，因此密度、硬度及導電度並無明顯變化。

關鍵字

銅基複合材料 ； 機械合金化法 ； 氧化物散佈強化

並列摘要

Pre-alloy Cu-Al（10wt％）powder is used for preparing oxide dispersion strengthen（ODS）composite powder through mechanical alloy（MA）method in normal atmospheres. Milling time is controlled form 0hr to 40hr , and 4hr as an unit. The process of phase change and morphology of particles are analyzed by XRD, SEM , EDS , TEM and Laser light scattering. Al atom precipitates in the Cu lattice is identified form the XRD results due to the diffraction peak shift and lattice parameters variation. Dispersion of the Al precipitation second phase is also observed by SEM. And the component of the precipitation phase is alumina confirmed by EDS and TEM. A homogeneous and nano-sized oxide dispersion strengthened Cu base composite powder is obtained with BPR 80 at 30℃and 600rpm for 24hr.
24 hour milled composite powder is then hot pressed of uniaxial to form bulk. A 92%relative density of Cu base composite is obtained with 65MPa hot press at 950℃ for 30 minutes. The hardness of Cu base composite is much higher than that of pure capper. The improve of mechanical properties is due to the block of dislocation by dispersion of alumina. The content of alumina also affect the electrical and mechanical properties of Cu base composite material. The bending strength and electrical conductivity increases as the alumina increases, but the hardness decreases. The density, hardness and electrical conductivity of 20% hot rolled Cu base composite material show no obvious variation due to the degradation of plasticity of high content of alumina.

並列關鍵字

Cu-matrix composite ； Mechanical Alloying ； Oxide dispersion strengthened

參考文獻

[1] P.S Gilman and J.S Benjamin , Mechanical Alloying , Ann.Rev.Mater.Sci. , 13（1983）279

[2] C.C Koch , O.B. Cavin , C.G. Mckamey and J.O. Scarbeough , Preparation of “amorphous” Ni60Nb40 by Mechanical Alloying Appl. Phys.Lett.43（1983）1017.

[3] C. Poltits , Amorphous Superconducting Nb3Ge and Nb3Ge1-xAlx Powders Prepared by Mechanical Alloying , J.de Physique. , 46（1985）C8-573

[4] F.Petzoldt , Synthesis and Process Characterization of Mechanically Alloyed Amorphous Ni-Nb Powders , J. Less-Common Met., 140（1988）85.

[5] P.Y. Lee and C.C. Koch , The formation and Thermal Stability of Amorphous Ni-Nb Alloy Powder Synthesized by Mechanical Alloying , J. Non-Cryst. Solids , 94（1987）88.