基于第一性原理的新型三元可加工陶瓷理论设计及实验验证

项目名称： 基于第一性原理的新型三元可加工陶瓷理论设计及实验验证

项目编号： No.11302061

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 柏跃磊

作者单位： 哈尔滨工业大学

项目金额： 25万元

中文摘要： 一类三元层状可加工陶瓷材料MAX相由于具有金属和陶瓷的共同性能而受到广大材料研究者的广泛关注，具有广阔的应用前景。理论预测具有优异工程性能的新型MAX材料是目前的研究热点之一，其中它的物相稳定性扮演了核心角色。然而由于物相稳定性在本质上是一个动力学问题，因而目前单纯基于热力学的分析方法难以准确预测MAX相的稳定性。针对这一问题，本课题将采用第一性原理计算方在本征稳定性分析基础上，重点从热力学和动力学分析和研究MAX相化合物的形成规律和内在机制，综合考察物相稳定性，建立理论分析模型。具体地，通过比较体系中MAX相与其它所有竞争相的能量差研究热力学稳定性；计算相关化学反应和多态性相变的势垒，考察动力学稳定性。然后，通过控制晶格空位、掺杂和固溶等方法理论设计和预测具有优异工程性能的新型MAX相材料，并在实验中进行初步验证。该课题将从新的视角阐明MAX相的形成机制，为新材料的理论设计奠定基础。

中文关键词： 三元层状化合物；第一性原理；物相稳定性；二维过渡金属碳化物；晶格动力学

英文摘要： A class of layered ternary MAX compounds have attracted great attention due to its unique combination of both metal- and ceramic-like properties, which render it to be the suitable candidature for many structural and functional applications. It is one of the interesting research topics to theoretically predict new MAX compounds, where the phase stability plays a critical role. However, the present method based on the chemical thermodynamics could not predict the phase stability accurately because it is a kinetical problem in origin. To concern this problem, the present project is going to investigate general trend and intrinsical mechanism for the formation of MAX phases, examine their phase stability overall, and build theoretical analytical model, after the intrinsic-stability study using First-principle. In detail, the thermodynamical research would be conducted by comparing the energy of MAX phases with all the competing phases; the kinetical study would be completed by concerning the energy barrier of possible reaction. Then, new MAX compounds with excellent performance for potential engineering application would be designed using some means, such as vacancy, solid solution, doping and so on. These predictions would be verified experimentally. The project will clarify the formation mechanism of MAX phases f

英文关键词： Ternary layered compounds；First principles；Phase stability；2D transition-metal carbides；Lattice dynamics