采用分子动力学方法对金属和非金属材料薄膜的导热系数进行数值模拟. 非金属材料氩的粒子间相互作用势采用12/6 L-J势能模型,金属材料钨使用MEAM势能模型. 模拟结果表明,非金属材料氩的导热系数与已有实验结果符合较好,但金属材料钨的导热系数结果较实验结果小1~2个数量级. 研究结果表明,引入自由电子导热模型能较准确预测金属材料钨的导热系数变化规律.
NEMD and EMD simulations were performed to calculate thermal conductivities of solid materials. We used 12/6 L-J potential model for nonmetallic material argon and MEAM potential model for metal materials tungsten. Simulation results show that the thermal conductivities of nonmetal material argon are in good agreement with experimental results but the thermal conductivities of tungsten are 1-2 orders smaller than experimental results. Incorporation of free electron effect can lead to accurate thermal conductivity of tungsten.
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