通过准谐方法重新审视第一性原理热力学：在增材制造Inconel 625热膨胀研究中的应用
Revisiting first-principles thermodynamics by quasiharmonic approach: Application to study thermal expansion of additively-manufactured Inconel 625
AI总结：
本研究改进基于DFT的QHA方法，分别计算自由能各贡献项并用AICc选模拟合，以增材制造IN625为例验证其热膨胀系数预测准确性，同时分析结构构型带来的预测敏感性与不确定性。
摘要：
本研究通过重新审视基于密度泛函理论（density functional theory, DFT）的准谐方法（quasiharmonic approach, QHA），开发了一种可精确测定随温度变化的热力学性质的创新方法。该方法分别计算静态总能、声子和热电子对自由能的贡献，以提升计算效率与准确性。采用带校正的赤池信息准则（Akaike information criterion with a correction, AICc）选择模型及模型参数，对各贡献项随体积的变化关系进行拟合。以增材制造的Inconel 625合金（IN625）为例，预测的随温度变化的线性热膨胀系数（coefficient of thermal expansion, CTE）与膨胀仪测量结果及文献值吻合良好。此外，还分析了DFT采用的不同结构构型（及由此确定的不同平衡性质）导致的IN625 CTE预测结果的敏感性与不确定性。
英文摘要：
An innovative method is developed for accurate determination of thermodynamic properties as a function of temperature by revisiting the density functional theory (DFT) based quasiharmonic approach (QHA). The present methodology individually evaluates the contributions from static total energy, phonon, and thermal electron to free energy for increased efficiency and accuracy. The Akaike information criterion with a correction (AICc) is used to select models and model parameters for fitting each contribution as a function of volume. Using the additively manufactured Inconel alloy 625 (IN625) as an example, predicted temperature-dependent linear coefficient of thermal expansion (CTE) agrees well with dilatometer measurements and values in the literature. Sensitivity and uncertainty are also analyzed for the predicted IN625 CTE due to different structural configurations used by DFT, and hence different equilibrium properties determined.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
