杂质成分对铀部件贮存性能影响及抗腐蚀技术研究

项目名称： 杂质成分对铀部件贮存性能影响及抗腐蚀技术研究

项目编号： No.11474358

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 数理科学和化学

项目作者： 何彬

作者单位： 中国人民解放军火箭军工程大学

项目金额： 50万元

中文摘要： 铀是重要的国防和核能领域核材料，经过加工形成铀金属部件后，广泛应用于核武器和核反应堆中。但由于C、Fe、N、S等杂质的存在，在长时间贮存、使用过程中，在空气中H2、O2、H2O诱导作用下，铀金属部件很容易与内部杂质成分发生化学反应，形成多种腐蚀产物或者共析物，这些腐蚀产物或者共析物将在铀金属部件表面和基体内形核，并不断生长和累积，出现软化、倒刺、腐蚀坑等老化现象，从而极大地影响铀金属部件的使用性能。因此，本课题拟用第一性原理、分子动力学和热力学等方法，研究杂质原子/分子在铀部件表面的化学吸附行为、基体内部的扩散过程、腐蚀产物或共析物形核及其聚集和生长过程，提出铀部件延缓和抗腐蚀的技术措施。预期研究成果为解释铀部件的微观老化机理和腐蚀现象的成因提供重要的技术支持。

中文关键词： 晶体缺陷；晶体结构；分子动力学；第一性原理计算；电子结构

英文摘要： Uranium is an important nuclear material of defence and nuclear power, and extensively applied in nuclear weapon and nuclear reactor when shaped into uranium components. However, during the long-time storage and usage, uranium components readily react with the impurities (such as C, Fe, N and S) induced by H2, O2 and H2O in the air, form several corrosion products or eutectoid products. These products may nucleate on the surface of uranium components, diffuse in the matrix, continuously grow and accumulate. Finally, these microscopic effects result in some phenomenon, such as soften, barb and etch pit, and greatly affect the service performance of uranium components. Therefor, we will couple the first principle, molecular dynamics and thermodynamics methods to research the chemisorption behavior of impurities on the surface of uranium components, the diffusion process in the matrix, and the accumulation and growth process of corrosion products or eutectoid products. Finally, we will present the retarded and anti-corrosion techniques for uranium components. The research achievements can be helpful for providing an important technical support for understanding the microscopic aging mechanisms and the reasons for corrosion phenomenon.

英文关键词： crystal defect;crystal structure;molecular dynamics;first principle calculation;electronic structure