機械合金化合成鎂鋅釔準晶粉末之研究

Synthesis of Mg-Zn-Y Quasicrystalline Powders by Mechanical Alloying

竇自強(Tz-Chiang Dou)

指導教授 ： 吳新明

大同大學/工程學院/材料工程學系所/碩士(2005年)

摘要

本研究利用機械合金化法合成含Mg-Zn-Y準晶相的粉末。發現準晶相Mg3Zn6Y能在準晶成分Mg30Zn60Y10直接經過2小時球磨後獲得。準晶周圍成分則容易形成Mg的固溶體，需再經過300℃的退火才會生成準晶。準晶相在300℃以下穩定，在400℃時會轉變為MgZn2及YZn5。靠近Mg3Zn3Y2立方相的成分則不會有準晶相的生成。球磨Zn含量較多的成分Mg20Zn70Y10則直接生成YZn5。

關鍵字

機械合金化 ； 鎂鋅釔 ； 準晶

並列摘要

The synthesis of Mg-Zn-Y quasicrystalline powders by mechanical alloying was investigated in this study. The results indicate that Mg3Zn6Y quasicrystal can be obtained directly by milling the pure Mg, Zn, Y powders of Mg30Zn60Y10 composition for 2 hours. However, milling the powders with compositions in the neighborhood of stoichiometric Mg3Zn6Y quasicrystal creates the Mg solid solutions, which transform to the Mg3Zn6Y quasicrystal by annealing the milled powders at 300℃. The Mg3Zn6Y quasicrystal is stable below 300℃. At 400℃ it transforms to MgZn2 and YZn5 phases. No quasicrystalline phases were formed upon milling the compositions near the cubic Mg3Zn3Y2 phase. For the initial composition Mg20Zn70Y10, which is close to Zn end in the Mg-Zn-Y phase diagram, milling directly creates YZn5 phase.

並列關鍵字

mechanical alloying ； Mg-Zn-Y ； quasicrystal

參考文獻

1.David R. Nelson. Scientific American.

3.Z. M. Stadnik ed., Physical Properties of Quasicrystals, Springer, New York, 1999.

7.D. H. Bae, S. H. Kim, W. T. Kim, and D. H. Kim, Mater. Trans. JIM, vol.42, p.2144, 2001.

8.D. H. Bae, S. H. Kim, D. H. Kim, W. T. Kim. Acta Materialia, vol.50, p2343, 2002.

11.C. Suryanarayana. Prog. Mater. Sci., vol.46, p1, 2001.