Viscosities of liquid metal alloys from nonequilibrium molecular dynamics
نویسندگان
چکیده
We have developed a nonequilibrium molecular dynamics (NEMD) approach to predict viscosity by including external shear rates directly into the Hamiltonian equations of motion. Using the quantum Sutton-Chen (Q-SC) many-body potentials for Au and Cu, we applied NEMD to predict the viscosity as a function of shear rates for AuxCu1 x alloys with x ranging from 0 to 100%. This was done for temperatures of 1500K to 2000K. The predicted viscosities are in reasonable agreement with experiment. In particular, we nd that xing the density and changing the temperature leads to very little change in the shear viscosity. Thus, the temperature dependence of viscosity is due mainly to the change in density with temperature. 83.20.Jp, 83.20.Di, 83.50.Ax, 83.80.Pc, 61.25.Mv, 61.66.Dk *To whom correspondence should be addressed.
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تاریخ انتشار 1998