项目名称： 新型核堆体用铁素体钢的纳米特征结构与氦吸收特性研究

项目编号： No.51471189

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 一般工业技术

项目作者： 江勇

作者单位： 中南大学

项目金额： 84万元

中文摘要： 纳米特征铁素体钢是一种以铬铁合金为基体的析出强化型新合金，是新一代核裂/聚变反应堆用理想堆体结构材料。通过特殊粉末冶金方式制备，在基体中原位析出大量、弥散、纳米尺度特征的(Y-Ti-O)原子簇团、以及近或非化学计量比的(Y/Ti)复杂氧化物，与基体的细晶组织和高密度位错一起，为该合金获得优良综合力学性能,以及抗辐照损伤、嬗变氦吸收等特殊性能。基于已有工作基础，本项目提出，针对合金中的特殊纳米析出结构，(1)综合运用第一原理计算和现代实验表征技术相结合的研究手段，深入研究纳米析出物的微结构及其界面结构和性质，（2）从原子\电子尺度揭示纳米结构与该合金特殊氦吸收能力的相关性，（3）阐明该合金中氦泡的形成机制，并预测氦泡长大和最终形态，（4）通过实际制备介观界面和辐照模拟实验，进行验证性研究。本项目开展，有助于该型合金的改进优化，也为今后高性能合金和金属基复合材料设计和研究，提供新的思路和参考。

中文关键词： 铁素体钢；析出相；纳米结构；界面结构

英文摘要： Nano-featured ferritic alloys (NFAs) are a new group of dispersion strengthening alloys and have promising applications for new generation fission/fusion reactors. Fabricated by advanced powder metallurgical techniques, NFAs hosts a Fe-Cr alloy matrix which is uniformly embedded with an ultrahigh density of nano-sized precipitates. These nano-features consist of (Y-Ti-O) atom clusters and near- or non-stoichiometric Y-Ti complex oxides, which, along with fine grains and the high dislocation density, are ultimately responsible for remarkably high tensile, creep and fatigue strength of NFAs, as well as good absorption of transmutant helium, and innate resistance to radiation damage. This project, as the continuation and deepening of our earlier studies, is aimed to undertand the microstructure and properties of nano-features (nano-clusters and nano oxide phases) and their interfaces, and their interrelation with the unique property of NFAs in managing helium. To meet this aim, we propose to carry out combinational studies of first-principles calculations and state-of-art experimental caracterizations, to elucidate the possible mechanisms for helium trapping and absorption, and predict the formation, growth and eventual fate of helium bubbles in NFAs. Fabrication of mesoscopic interface samples and subsequent irradiation experiments will be also performed, to validate our thereotical results. These efforts help provide useful knowledge and guidance for the optimal design of NFAs. They also provide new research methodology and case studies for future developmenet of high performance alloys and metal matrix composites.

英文关键词： Ferritic Alloy;Precipitate;Nano Structure;Interface structure