基于AKMC方法研究Mn对Cu团簇析出的影响

Cu团簇析出是影响FeCu合金体系安全服役的主要因素之一。本文基于原子动力学蒙特卡罗（AKMC）方法研究了热老化条件下，合金元素Mn对Fe-1.34at.%Cu-Xat.%Mn（X为0、0.27、1.2、3、5）合金中Cu团簇析出的影响。研究结果表明，随着体系中Mn含量的增加，析出形核的纳米级Cu团簇的数密度不断增加；Mn含量对形核Cu团簇的平均尺寸影响不大。团簇中主要成分为Cu；团簇中Mn含量随初始基体中Mn含量的增加而增加。合金元素的成团参与百分比决定了团簇平均尺寸。Cu-Vac复合体较强的扩散能力及其较远的扩散距离是造成Cu团簇析出的主要因素；而Mn的加入会抑制Cu-Vac复合体的可移动距离和可移动能力，从而提高Cu团簇的数密度。合金元素Mn的加入会影响形核Cu团簇的尺寸、数密度，从而影响Cu团簇引起的硬化效应。

Effect of Mn on Formation of Cu-enriched Cluster Based on AKMC Method

The formation of Cu-enriched clusters is one of the main factors affecting the safe service of FeCu alloy. Based on the AKMC (atomic kinetic Monte Carlo) method, the effect of alloy element Mn on the formation of Cu-enriched clusters during thermal ageing in the Fe-1.34at.%Cu-Xat.%Mn (X is 0, 0.27, 1.2, 3, and 5) alloy was studied. The research results show that with the increase of Mn content in the alloy, the number density of nano-scale Cu-enriched clusters continues to increase, and Mn content has little effect on the average size of Cu-enriched clusters. The cluster is enriched in Cu, and the Mn content in the cluster increases with the Mn content in the matrix. The percentage of alloy elements involved in the formation of clusters determines the average cluster size. The higher diffusion ability and longer diffusion distance of the Cu-Vac complex are the main factors that cause the precipitation of Cu-enriched clusters, and the addition of Mn will inhibit the diffusion mobility of the Cu-Vac complex, thereby increasing the number density of the cluster. The addition of alloy element Mn will affect the size and number density of Cu-enriched clusters, thereby affecting the hardening effect caused by Cu-enriched clusters.