The role of size and composition in the melting and solidification behaviors of Ag-Cu-Au ternary nanoalloys: An atomistic approach

Abstract

Metal ternary nanoalloys are novel materials in different fields due to the synergy of three metals in a single block that leads to unique physical properties as compared to monometallic nanoparticle. In the present poster, the size and composition effects on the melting and solidification points of Ag-Cu-Au nanoalloys are analyzed using molecular dynamics simulations. Our results, for size influence, indicate that the melting points follow a scaling law for all the nanoalloys studied ($𝑇_𝑚=𝑇_𝑚^𝑏𝑢𝑙𝑘−𝑎𝑁^(−1/3)$), yielding a value lower than that of the bulk alloy. Furthermore, solidification points show no dependence on size. For composition influence, indicate that the melting point present linear and quadratic dependencies with the composition (𝑥), i.e. for Cu33Ag67-xAux, Ag33Cu67-xAux and Au33Ag67-xCux are $𝑇_𝑚=912.6+1.9𝑥$, $𝑇_𝑚=882.3+2.7𝑥$, and $𝑇_𝑚=1056.6−4.9𝑥+0.07𝑥^2$, respectively. Besides, the solidification points show no relationship to the composition either. Finally, most Ag atoms segregate to the surface and the Au and Cu atoms are localized in the center of the system during heating stage, and this trend is maintained in the cooling stage.

Keywords: Metal ternary nanoalloys; melting and solidification temperature; molecular dynamics simulations