辐照环境下液态铅对铁基材料溶解腐蚀的分子动力学模拟研究

项目名称： 辐照环境下液态铅对铁基材料溶解腐蚀的分子动力学模拟研究

项目编号： No.11505214

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 数理科学和化学

项目作者： 张艳革

作者单位： 中国科学院合肥物质科学研究院

项目金额： 23万元

中文摘要： 加速器驱动的次临界核能系统在嬗变核废料的同时能产出洁净能源。制约该系统运行的瓶颈之一是结构材料要同时承受液态金属腐蚀和高能质子/中子辐照损伤。实验表明辐照会加剧液态金属对铁基结构材料的溶解腐蚀，但辐照损伤与液态金属对其溶解腐蚀协同作用机理尚不清楚。因此，本项目拟开展辐照环境下，液态铅对铁基材料溶解腐蚀的分子动力学模拟研究（受势函数限制，本项目选液态铅为代表探讨液态金属对结构材料溶解腐蚀机理）。以α-Fe为研究对象，结合经典分子动力学和分子静态计算方法，通过大体系（几万个原子）在无辐照缺陷、单次PKA作用下的辐照缺陷和多次PKA作用下的累积辐照缺陷情形下液态铅溶解腐蚀过程的对比研究，同时引入温度和表面取向变化，系统考察Fe表面辐照缺陷与液态铅相互作用的微观动态过程、能量学和动力学性质，揭示辐照损伤与液态铅对Fe基材料溶解腐蚀协同作用机理，为研发辐照环境下抗溶解腐蚀核材料提供理论数据基础。

中文关键词： 溶解腐蚀；辐照损伤；协同作用；分子动力学模拟

英文摘要： The accelerator driven systems could burn up nuclear waste and produce clean energy meanwhile. One of the bottlenecks hindering the operation of the system is that the structural materials would enduring the liquid metal corrosion and the proton\neutron irradiation damage simultaneously. Experiments show that irradiation could aggravate the liquid metal corrosion to the iron-based structural materials. But the synergy mechanism of the irradiation damage and liquid metal dissolution corrosion to the structural material is not clear yet. This project would perform the theoretical study on the dissolution corrosion of liquid lead for the iron-based materials under irradiation environment. (Here, this project takes lead as a representation to study the dissolution of liquid metal to structural material due to the restriction of potential function). Based on α-Fe, through the comparison of the liquid lead dissolution corrosion process under three conditions: without irradiation defects, the irradiation defects after single PKA bombard and the accumulated irradiation defects after many PKA bombard for the large systems (tens of thousands of atoms), while introducing the temperature and surface orientation variation, the classic molecular dynamics and molecular statics are performed to study the dynamic micro-process，the energetic and dynamic properties of the interaction between irradiation defects and liquid Pb. The synergy mechanism of the irradiation damage and liquid metal to the dissolution corrosion of Fe-based materials could be revealed to provide theoretical database for designing the nuclear materials that resist dissolution corrosion under irradiation environments.

英文关键词： dissolution corrosion;irradiation damage;synergistic effect;molecular dynamic simulation