Abstract:

The investigations of thermal conductivity of materials are important to understand their characteristics and their influences. In simulation-based studies, many researchers used molecular dynamics (MD) simulation to analyze the thermodynamic properties. In this paper, non-equilibrium molecular dynamics (NEMD) simulations based on uniform internal heat source are performed to determine the thermal conductivity of nickel material by using Lenard-Jones potential model and EAM potential model. Simulation results based on different potential models are achieved and analyzed. Based on this, the thermal conductivity of copper and nickel-copper solid solution were simulated. The EAM potential model was further validated by achieving reasonable results for copper. And the optimized Ni-Cu ratio for lower thermal conductivity of solid solution were modeled based on the EAM model.

Key words: molecular simulation, model, thermodynamic properties, nickel, copper, thermal conductivity

摘要：

热导率的求解及优化具有重要的研究价值和实际意义,分子动力学是计算体系热力学量和其他宏观性质的一种有效方法。采用一种基于均匀内热源的非平衡分子动力学(NEMD)方法,分别选取Lennard-Jones势能模型和EAM势能模型,对镍的热导率进行模拟,对比二者结果发现考虑了电子影响的EAM势能模型比L-J模型更接近获得与实际值吻合良好的结果。继续选取EAM模型对铜以及镍铜复合材料的热导率进行模拟分析,进一步验证了EAM势能模型对金属铜热导率的模拟可行性,同时模拟分析了不同配比的镍铜复合材料的热导率,为获得最低有效热导率值及其配比进行了初步模拟分析并提供了理论支撑。

关键词: 分子模拟, 模型, 热物性, 镍, 铜, 热导率