Subregular Model For The Formation Enthalpy Of Cu-based Nanoalloys

Formation enthalpy is an important physical quantity that describes the ability of alloys formation.Materials in the nano-size has special electrical,optical,magnetic and mechanical properties,making it have been a hot research.In this paper,the noble metal and Cu were selected as the research object.Considering the surface forming enthalpy,the relationship between the enthalpy of formation and the particle size and alloy composition was calculated by using the subregular model.It is found that the formation enthalpies of Cu-Ag,Cu-Au,Cu-Pt,Ag-Pd,Au-Ag and Au-Pt block alloys are in good agreement with the calculated results and experimental values of other models.By calculating formation enthalpies of binary nanometer alloy forming between Cu,Rh,Ru,Ag,Pd,Au,Pt,Pt,Os and Ir,it is found that the obvious composition segregation of Cu-Pt will occur and the direction of segregation is related to the aggregation driven energy of the alloy.By calculating the formation enthalpy of nano-ternary Cu-based alloy,the formation area of nanoalloys increases with the increase of nano-size.Through the calculation we found that nano forming region of Cu-Au-Pt-Pd and Cu-Au-Ag-Pt increases with the increase of Cu content,while that of Cu-Au-Ag-Pd decrease with the increase of Cu content.