Molecular Dynamics Simulation on Effect of Y Content on Mechanical Properties of Cu-Zr Based Amorphous Alloys

In order to shorten the period of researching new Cu-Zr-based amorphous alloys by using a single experimental method and reduce the development cost, the molecular dynamics simulation method was used.The effects of Y content on the mechanical properties of Cu-Zr-based amorphous alloys were studied. The enthalpy of formation method was confirmed that Y doping tends to occupy the Zr atomic position. Amorphous alloys with four composition ratios of Cu₆₄Zr₆₄,Cu₆₄Zr₆₃Y, Cu₆₄Zr₅₉Y₅and Cu₆₄Zr₅₄Y₉(correspondingly rewritten as atomic percentages, namely Cu₅₀Zr₅₀, Cu₅₀Zr_49.2Y_0.8,Cu₅₀Zr_46.1Y_3.9and Cu₅₀Zr_42.1Y_7.9) were prepared by simulation, and the atomic model of amorphous alloys was established. The RDF （Radial distribution function） was used to analyze the degree of disorder of the amorphous alloy structure; the constant strain method was used to calculate the elastic modulus of the constructed model. Based on the relationship between the elastic modulus and the tensile strength and hardness of the amorphous alloy Qualitative relationship, the mechanical properties of amorphous alloys were infered. The results show that Y doping enhances the mechanical properties of Cu-Zr based amorphous alloys, and with the Y content increasing from 0 at% to 3.9 at%, the elastic model of the amorphous alloy increases from 39GPa to 90 GPa, but when the Y content is furtherly increased to 7.9 at%, the elastic modulus of the amorphous alloy drops sharply to 68 GPa, that is, the Cu₆₄Zr₅₉Y₅amorphous alloy with 3.9 at% Y content has the best mechanical properties.