纳米尺度晶体/非晶复合材料的耐辐照特性研究

项目名称： 纳米尺度晶体/非晶复合材料的耐辐照特性研究

项目编号： No.51501225

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 一般工业技术

项目作者： 于开元

作者单位： 中国石油大学（北京）

项目金额： 21万元

中文摘要： 在核反应过程中，高能粒子轰击金属材料导致大量缺陷（间隙原子、空位、位错环、孔洞等），造成材料硬化、肿胀和脆化。近年来，具有高密度晶体/晶体界面的纳米结构材料（纳米晶、纳米多层膜、纳米孪晶等）由于可有效吸收辐照缺陷，而引起极大关注。然而，晶体/晶体界面（共格、半共格、非共格）容纳缺陷能力有限。基于晶体/非晶界面具有高容纳缺陷能力，最近，申请者对含有纳米尺度晶体/非晶界面的Cu-Nb复合材料的耐辐照特性进行探索，采用原位辐照观察发现：在辐照过程中，晶体相中缺陷呈“泉涌”状向晶体/非晶相界面迁移并湮灭的独特现象，且复合材料表现辐照软化及良好的耐辐照性能。本项目拟揭示纳米尺度晶体/非晶相复合材料内部辐照缺陷的演变特征与机制，阐明各相辐照稳定性机制，澄清辐照软化的特征与机制，建立纳米尺度晶体/非晶复合材料的耐辐照基本理论，可望获得高水平学术成果。

中文关键词： 辐照损伤；界面；晶体/非晶；复合材料

英文摘要： High energy particles generated by nuclear reactions can cause high density defects (interstitials, vacancies, dislocation loops and voids etc.) to metals and alloys, resulting in hardening, void swelling and embrittlement. Recently, nanostructured materials (nanograins, nanolayers and nanotwins) has attracted increasing attention due to their efficiency of absorbing radiation induced defects via high density crystalline/crystalline (C/C) interfaces. However, C/C interfaces have limited free volume for defect-capture. Based on the fact that larger free volume exists at crystalline/amorphous (C/A) interfaces, the applicants try to enhance the radiation tolerance of Cu-Nb nanocomposite by introducing abundant C/A interfaces. We have observed that the radiation induced defects in such materials migrated towards interfaces like water welled up in a spring. We have also found the radiation induced softening and overall excellent radiation resistance in the material. This project is to unveil the mechanism of defect evolution in nanocomposite with C/A interfaces, to explore the mechanism of phase stability and to understand the deformation mechanism of radiation induced softening. This project is expected to establish fundamentals of the radiation resistance of nanocomposite with C/A interfaces and to obtain high-quality academic achievements.

英文关键词： radiation damage;interface;crystalline/amorphous; composite material