Empirical interatomic potential for Fe-C system using original Finnis-Sinclair potential function
Empirical interatomic potential for Fe-C system using original Finnis-Sinclair potential function
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使用原始 Finnis-Sinclair 势函数计算 Fe-C 体系的经验原子间势
DOI：
10.1016/j.commatsci.2020.109871
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发表时间：
2020
影响因子：
3.3
通讯作者：
Tsuchiyama Toshihiro
中科院分区：
文献类型：
--
作者：
Hyodo Katsutoshi;Munetoh Shinji;Tsuchiyama Toshihiro
Finnis-Sinclair（FS）势是三体势中势函数最简单的一种。本文在不改变原函数形式的前提下，导出了Fe-C二元系的FS势。确定了Fe-C和C-C相互作用的势参数，以拟合γ′-Fe_4C、θ-Fe_3C、χ-Fe_5C_2o-Fe_7C_3和NaCl型Fe_3C的物理性质（结构参数、体积模量和结合能）。开发的势再现了体心立方（bcc）和面心立方（fcc）铁中的十四种铁碳化物和间隙碳原子的迁移能垒。此外，还证实了铁原子的声子态密度（θ-Fe_3C）和六方铁原子的声子态密度（h-Fe_7 C_3）的可重复性，碳原子在体心立方铁中的扩散系数与实验值符合得很好。
The Finnis-Sinclair (FS) potential is one of the three-body potentials and the potential function is the simplest in them. We developed the FS potential for an Fe-C binary system without changing the original form of the function. The potential parameters for the Fe-C and C-C interactions were determined to fit the physical properties (structural parameters, bulk modulus and cohesive energy) of five iron carbides (γ′-Fe4C,θ-Fe3C,χ-Fe5C2ο-Fe7C3and NaCl type-FeC). The developed potential reproduced fourteen iron carbides and migration energy barriers of interstitial carbon atoms in body-centered cubic (bcc) and face-centered cubic (fcc) irons. Moreover, the reproducibility of the phonon densities of states for the iron atoms of cementite (θ-Fe3C) and hexagonal-Fe7C3(h-Fe7C3) was confirmed and the diffusion coefficient of carbon atoms in bcc iron was good agreement with the experimental value.