Reduced dependence of thermal conductivity on temperature and pressure of multi-atom component crystalline solid solutions
Reduced dependence of thermal conductivity on temperature and pressure of multi-atom component crystalline solid solutions
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DOI：
10.1063/1.5010337
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发表时间：
2018-01
影响因子：
3.2
通讯作者：
A. Giri;Jeffrey L. Braun;P. Hopkins
中科院分区：
文献类型：
--
作者：
A. Giri;Jeffrey L. Braun;P. Hopkins
通过分子动力学模拟研究了质量无序、温度和压力对多组分晶体固溶体光谱导热系数的影响。模拟了晶格中含有1-5个不同原子组分的Lennard-Jones基固溶体在一定的单轴应变水平和温度范围内的热导率。我们的结果表明，对于多元合金，仅仅通过在固溶体中加入不同质量的原子来增加杂质的质量散射，并不会导致光谱对导热系数的贡献发生显著的变化。然而，增加杂质浓度或改变固溶体中杂质原子的局域力场对热导率的光谱贡献有比较显著的影响。由于不同的散射机制决定了合金的热稳定性，这些合金中的化学有序效应显著地改变了与温度的关系。
We investigate the effect of mass disorder, temperature, and pressure on the spectral thermal conductivity of multicomponent crystalline solid solutions via molecular dynamics simulations. The thermal conductivities of Lennard-Jones based solid solutions with one to five different atomic components in the crystalline lattice are simulated at a range of uniaxial strain levels and temperatures. Our results show that for multicomponent alloys, increasing only the mass impurity scattering by adding atoms with different masses in the solid solution does not lead to significant changes in the spectral contributions to thermal conductivity. However, increasing the impurity concentration or changing the local force-field of the impurity atoms in the solid solution has a relatively significant impact on the spectral contributions to thermal conductivity. The effect of chemical order in these alloys is shown to drastically alter the temperature dependence due to the different scattering mechanisms dictating thermal...