The early aging Cu precipitations in Fe-3%Cu and Fe-3%Cu-4%Ni ternary alloys are investigated by molecular dynamics （MD） simulations. The results show that the average size of Cu clusters in Fe-3%Cu-4%Ni alloy is la...The early aging Cu precipitations in Fe-3%Cu and Fe-3%Cu-4%Ni ternary alloys are investigated by molecular dynamics （MD） simulations. The results show that the average size of Cu clusters in Fe-3%Cu-4%Ni alloy is larger than that in Fe-3%Cu alloy. The diffusion of Cu is accelerated by Ni according to the mean square displacement （MSD）. Furthermore, the whole formation process of Cu-rich clusters is analyzed in detail, and it is found that the presence of Ni promotes small Cu-rich clusters to be combined into big ones. Ni atoms prefer to stay at the combination positions of small clusters energetically due to a large number of the first nearest neighbor Cu-Ni interactions, which is verified by first-principles calculations based on density functional theory （DFT）.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.50931003 and 51301102)the 085 Project at Shanghai University,China.
文摘The early aging Cu precipitations in Fe-3%Cu and Fe-3%Cu-4%Ni ternary alloys are investigated by molecular dynamics （MD） simulations. The results show that the average size of Cu clusters in Fe-3%Cu-4%Ni alloy is larger than that in Fe-3%Cu alloy. The diffusion of Cu is accelerated by Ni according to the mean square displacement （MSD）. Furthermore, the whole formation process of Cu-rich clusters is analyzed in detail, and it is found that the presence of Ni promotes small Cu-rich clusters to be combined into big ones. Ni atoms prefer to stay at the combination positions of small clusters energetically due to a large number of the first nearest neighbor Cu-Ni interactions, which is verified by first-principles calculations based on density functional theory （DFT）.
