Viscosities and their correlations with structures of Cu-Ag melts

The viscosities of a series of Cu-Ag melts in a temperature range from 1473 K to nearly liquid temperatures are measured by using an oscillating viscometer. At the same temperature, the value of viscosity increases first with silver content increasing, and reaches a maximum value at the eutectic component Cu₄₀Ag₆₀, then decreases. All the temperature dependences of the viscosities of Cu-Ag melts conform with the Arrhenius equation. The parameters of correlation length D of the studied Cu-Ag melts are calculated according to the experimental results of x-ray diffraction. The temperature dependence of correlation length D shows an exponential decay function, which is similar to the Arrhenius equation. Based on the values of viscosities and correlation length D, a direct correlation between viscosity and liquid structure is found for the investigated Cu-Ag melts through comparative analysis.