機械化學研磨合成Al2O3/TiC奈米複合材料 及其耐蝕性研究

Mechanochemical Synthesis of Al2O3/TiC Nanocomposite and Their Corrosion Resistance

王世英(Shin-Ying Wang)

指導教授 ： 吳新明

大同大學/工程學院/材料工程學系所/碩士(2010年)

摘要

本實驗成功地以二氧化鈦、鋁粉及碳粉為初始成份，以震動式球磨機在氬氣保護氣氛下進行球磨，利用機械化學研磨法合成Al2O3/TiC奈米晶複合材料，並探討四種不同初始鋁含量合成氧化鋁莫耳分率及對Al2O3/TiC塊材耐蝕性質之影響。實驗首先根據熱力學計算出反應之總反應焓及反應自由能，決定反應可行之鋁含量範圍。經由XRD繞射分析結果，A、B兩種成份經球磨20小時能生成Al2O3/TiC複合粉末，C成份必須經過30小時；至於D成份則必須經球磨後再在高於1050C退火才能生成Al2O3/TiC複合粉末。經熱分析檢測，氧化鋁與碳化鈦繞射峰開始發生分離溫度約在1050 ℃而達1150 ℃後則完全分離。完全反應之複合粉末作粒徑分析之結果，發現粒徑分佈皆呈現常態分佈。在極化曲線中證實經Al2O3的複合提高碳化鈦基奈米晶複合材料的耐蝕性。

關鍵字

機械化學研磨 ； Al2O3 ； TiC ； 奈米晶複合材料 ； 極化曲線 ； 耐蝕性

並列摘要

In this study, Al2O3/TiC nanocomposites have been successfully synthesized by mechanochemical synthesis in the argon atmosphere with mixtures of TiO2, aluminum and carbon as starting powders. This research investigated the effect of different starting amounts, i.e. 0.4, 0.7, 1.0 and 1.3 moles aluminum respectively, on the formation of molar fraction of alumina and the corrosion resistance of synthesized nanocomposite. The total reaction enthalpies and Gibbs free energies of formation of composites were calculated by using thermodynamics and Hess’s law to determine the feasible range of Al contents. The XRD results showed that Al2O3/TiC composite powders were formed after 20 hours of milling for 1 and 1.3 mole starting Al contents. For 0.7 mole Al, the Al2O3/TiC composite powders were not formed until after 30 hours of milling. For 0.4 mole Al, Al2O3/TiC composite powders can’t be created through milling only, but can be formed after annealing on the milled powder at over 1050 ℃. The particle size measurement revealed that all these particle size distributions of composite powders exhibit normal distribution. The polarization test verifies that Al2O3 is conducive to the corrosion resistance of TiC composite.

並列關鍵字

mechanochemical synthesis ； Al2O3 ； corrosion resistance ； polarization test ； TiC ； nanocomposite

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