Monte Carlo simulation of thermophysical properties of Ni-15%Mo alloy melt

Abstract

The Monte Carlo method with EAM potential is used to simulate the liquid Ni-15%Mo binary alloy system, from which the thermophysical properties hardly measured by experimental measurement can be obtained. The simulated surface tension of liquid Ni-15%Mo alloy at the melting temperature is 1.918 N/m, and the simulated temperature coefficient of surface tension as a function of temperature is σ=1.918-1.130×10-3（T-Tm） N/m. Based on the simulated surface tension, the variation of viscosity and solute diffusion coefficient within the range of from 1500 K to 2000 K can be deduced. The result of the viscosity is η=0.895exp（2.209×104/RT） mPa·s, that is, the viscosity constant is 0.895 mPa·s, and the apparent activation energy is 2.209×104 J/mol. The diffusion coefficient can then be obtained by the Stokes（Sutherland）-Einstein equation as D=9.803×10-8exp（-3.643×104/RT） m/s2， where the activation energy is 3.643×104 J/mol. From the relationship between system energy and temperature, the specific heat of liquid Ni-15%Mo alloy at different temperatures can be determined to be Cp=37.313-1.425×10-2（T-Tm） J·mol-1·K-1.