Influence of Cu precipitation on tensile properties of Fe-Cu-Ni ternary alloy at different temperatures by molecular dynamics simulation

The influence of Cu precipitation on the tensile properties of Fe-1.1% Cu-0.9% Ni ternary alloy at different temperatures are analyzed using molecular dynamics ( MD) method. The local lattice structural transition around Cu-rich clusters is generated by Cu-rich clusters forming during continuous cooling process. The formation of Cu-rich clusters and matrix of local lattice structural transition result in the decrease of tensile yield strength of the matrix material at room temperature. Therefore, the matrix becomes brittle and tends to fracture in the local structural transition area. It has been found that the formation of Cu-rich clusters reduces the yield strength of the matrix more greatly at aging temperature than room temperature. Furthermore, the higher the temperature is, the greater the degree is. Cu-rich clusters play a significant role in strengthening material at early stage, while the material strength decreases with time increase. (C) 2016 Elsevier B.V. All rights reserved.