空位有序化的非化学计量过渡族金属碳化物氧化机制及相关现象研究

项目名称： 空位有序化的非化学计量过渡族金属碳化物氧化机制及相关现象研究

项目编号： No.51272225

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 一般工业技术

项目作者： 柳忠元

作者单位： 燕山大学

项目金额： 80万元

中文摘要： 过渡族金属碳化物（TMC）具有很多优良性能，如高熔点、高硬度、导电导热性好、热与机械稳定性高、耐化学腐蚀与辐射等，在高温结构和耐磨硬质合金材料领域应用前景广泛，国内外对此进行了大量的研究工作，然而，对于TMC优良特性的本质起源，迄今相关研究仍然不足，人们缺乏足够了解。特别是TMC的非化学计量性，碳原子缺失产生空位，空位有序分布有利于性能提高，而无序化导致性能下降。但是，采用传统烧结工艺制备非化学计量TMC，难以实现空位有序化。最近，采用火花放电等离子烧结技术，我们在非化学计量TiCx的烧结过程中直接实现了空位有序化，此特殊烧结工艺使深入研究空位有序非化学计量TMC成为可能。本项目针对非化学计量TMC展开研究，探索实现空位有序的最佳烧结工艺条件，揭示微观烧结机制，研究有序化空位在非化学计量TMC氧化中的作用机制、相关新现象与形成机理，为开发空位有序非化学计量TMC的应用前景提供实验支持。

中文关键词： 过渡族金属碳化物（TMC）；空位有序化；氧化；二氧化锆；二氧化钛

英文摘要： Transition metal carbides (TMC) have many excellent properties such as high melting point, high hardness, good thermal and mechanical stability, strong resistance to chemical corrosion and radiation, etc. Owing to these excellent properties, TMC exhibit wide applications in high-temperature structural materials and wea-resisting hard alloy materials. Nationally and internationally, huge amount of investigations have been performed on the applications of TMC. To date, however, the studies are not sufficient on the essential origins of these TMC excellent properties, and they are not known very much. Especially, TMC is nonstoichiometric. In the nonstoichiometric TMC, the lack of carbon atoms leads to the appearance of carbon vacancies. The ordered vacancies in the C sublattice is favorable for the improvement of TMC properties, while the disordered vacancies is detrimental to TMC properties. By the conventional sintering techniques, however, it is hard to realize the ordering distribution of carbon vacancies in the C sublattice of TMC. Recently, by using the spark plasma sintering (SPS) technique, we have directly obtained the ordered-vacancy nonstoichiometric titanium carbides (TiCx). Thus, this special SPS technique makes it possible to perform the extensive investigations on the ordered-vacancy nonstoichiometri

英文关键词： Transition metal carbide (TMC)；carbon vacancy ordering；oxidation；ZrO2；TiO2