预合金粉末内氧化过程中金属/氧化物界面的原位形成和结构演变研究

项目名称： 预合金粉末内氧化过程中金属/氧化物界面的原位形成和结构演变研究

项目编号： No.51474244

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 矿业工程

项目作者： 易丹青

作者单位： 中南大学

项目金额： 85万元

中文摘要： 金属/氧化物界面是一类非常重要的界面，申请人在以往国家科技支撑计划和国防科研项目的研究中，发现其对粉末冶金材料的物理力学性能有重要影响。本项目针对预合金粉末内氧化过程中金属/氧化物界面的原位形成和演变问题，以Ag/SnO2界面为具体研究对象，开展以下研究：(1)采用HRTEM等手段，深入表征内氧化界面结构特征；(2)借助第一性原理界面热力学计算，揭示内氧化界面结构稳定性与环境因素的相关性；(3)综合扩散动力学和界面热力学计算结果，建立制备过程中内氧化界面结构演变动力学模型；(4)以计算和实验结果为基础，预测界面结构、界面能量和结合强度。项目旨在揭示内氧化界面结构和界面性能随工艺条件演变的内在规律，发展将界面结构表征、第一性原理界面热力学、扩散动力学等相结合的界面研究新方法，为该类材料的成分和微结构设计以及制备工艺优化提供科学依据。

中文关键词： 粉末冶金；氧化物弥散强化；第一性原理；界面反应；微观结构

英文摘要： Metal/oxide interface is one of important interfaces. After experiment and calculation works during the fullfill of national key science and technology support program and national defence research project, we found that the physical and mechanical properties are very sensitive to metal/oxide interface. In this project, Ag/SnO2 interface will be taken as and example for the investigation of structure and energy of metal/oxide interface,which in-situ formed during internal oxidation of pre-alloyed powder.The research contents are as followings: (1) the internal oxidized interface will be better characterized by HRTEM, EFTEM and EELS; (2) the relationship between circustance factor and structure stability of interface will be investigated by the use of first principle interface thermodynamic; (3) the kinetic model of interface structure evolution during internal oxidation process will be constructed by the combination of diffusion kinetics and thermodynamics; (4) the interface structure, interface energy and interface bonding strength will be predicted on the basis of calculated and experimental results. The aims of this program are to reveal the law of interface structure and property evolution with the experiment conditions, develop a method for investigating interface by the combination of interface structure characterization, interface first-principle & thermodynamic calculation and diffusion kinetics, provide scientific basis for interface design, prediction of interface property and internal oxidation process.

英文关键词： powder metallurgy;oxide dispersion strengthening;first principle;interface reaction;microstructure