物理学报2017，Vol.66Issue(8)：273-284,12.DOI:10.7498/aps.66.086301
Fe基体中包含Cu团簇的Fe-Cu二元体系在升温过程中结构变化的原子尺度计算
Atomic-scale simulation study of structural changes of Fe-Cu binary system containing Cu clusters emb edded in the Fe matrix during heating
摘要
Abstract
Nano-size Cu precipitates are the main products of irradiation embrittlement of nuclear reactor pressure vessel steels. Molecular dynamics simulation within the framework of embedded atom method is performed to study atomic packing change in Fe-Cu binary system, where the small Cu clusters are embedded in the crystal body centered cubic (BCC) Fe lattices. As the temperature increases, atomic packing change occurs in the Fe-Cu binary system. The mean square displacement of Cu atom, pair distribution function of the Cu atoms, and the atomic density profile along the radial direction are calculated. The atom packing structures in pure Cu region, Fe-Cu interface region, and pure Fe matrix are analyzed. The simulation results show that the packing structures in the Cu cluster and the Fe matrix are greatly affected by the sizes of these clusters and the volume of the Fe matrix containing these clusters. The structural changes present apparent differences, for the Fe matrixes contain these confined Cu clusters with different atom numbers during heating. As the Fe matrix can only provide small space to accommodate the Cu atoms, packing patterns in many Cu atoms are disordered for the Febulk-Cu135 system. In this binary system, strain region in the Fe matrix is adjacent to the Cu cluster. In the meantime, there are a lot of vacancy defects and strain regions in the matrix. For the Febulk-Cu141 system, although the Cu cluster contains more atoms, the Fe matrix can accommodate Cu atoms in a larger space, and the majority of these Cu atoms are located at the BCC crystal lattices. With increasing the temperature, the changes can be observed that the number of the strain regions decrease, whereas the sizes of some strain regions increase.关键词
团簇/分子动力学/合金/界面Key words
cluster/molecular dynamics/alloy/interface引用本文复制引用
郑治秀,张林..Fe基体中包含Cu团簇的Fe-Cu二元体系在升温过程中结构变化的原子尺度计算[J].物理学报,2017,66(8):273-284,12.基金项目
国家自然科学基金 (批准号:51171044,51671051)、辽宁省自然科学基金 (批准号:2015020207) 和中央儈校基本科研业务费 (批准号:N140504001) 资助的课题. Project supported by the National Natural Science Foundation of China (Grant Nos.51171044,51671051),the Natural Science Foundation of Liaoning Province,China (Grant No.2015020207),and the Fundamental Research Fund for the Central Universities,China (Grant No.N140504001). （批准号:51171044,51671051）
