本文使用分子动力学方法对金属钨的熔化过程进行了数值模拟，分析了钨在熔化过程中的结构、系统内能变化以及表面熔化过程固一液界面变化情况，初步分析了表面熔化现象的机理。模拟过程采用嵌入原子模型（EAM）描述原子间相互作用，模拟结果表明，嵌入原子模型适合于计算固一液相变过程，表面熔化过程是由表面处最外层原子的不稳定性触发的。对于均匀熔化过程，晶体在4700K下发生固一液相变；对于表面熔化过程，计算获得了不同温度（3800-4800K）下的熔化速度，拟合出熔化速度公式，得到的表面熔化热力学熔点与已有实验结果基本符合。
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.
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