Molecular dynamics simulation of melting processes for metal W

Melting processes for metal tungsten are investigated using molecular dynamics simulation method. Crystal structure, solid liquid interface velocity and internal energy change of melting processes are simulated using different boundary conditions. Melting process mechanism is discussed as well. The embedded atom potential model is used to describe the interaction between atoms. The simulation results show that embedded atom potential model is suitable for the solid liquid phase change process and surface melting process is initiated by the surface instability triggered of outermost layer atoms. For homogeneous melting process, the crystal takes place solid liquid phase change at 4700 K. For the surface melting process, melting rate are calculated under different temperatures (3800-4800 K) and melting rate equation is fitted based on exponential function. The thermodynamic melting point of the surface melting result is consistent with existing experimental result.