Viscosity modeling of binary alloys: Comparative studies

The comparative analysis of experimental and calculated viscosity of binary alloys was performed applying models in which enthalpy or free enthalpy of mixing change is combined with the viscosity of components. Some models incorporate also densities, molar volumes of alloys or atomic radius of metals but the present considerations focused only on thermodynamic functions. The considerable discrepancies found for some systems referred on one hand to the sign of deviations of excess viscosity and on the other hand to significant deviations between the experimental and modeled values. Based on the conclusions derived from the former analysis, two new empirical models were proposed for the viscosity calculation. They allowed predicting the physical properties of binary alloys with better or comparable accuracy in comparison with the experimental data and also in most cases the right deviations of the excess viscosity. Because of the applied thermodynamic function the models were named “entropy models”.