Yong Xi, Liu Xiating, Yang Maosheng, Zhou Xiaolong
Institute for Special Steels, Central Iron and Steel Research Institute, Beijing 100081, China.
Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming 650093, China.
Materials (Basel). 2024 Jul 15;17(14):3498. doi: 10.3390/ma17143498.
In this paper, the stability, mechanical properties and electronic structure of carbides in steel were calculated using the first-principles method based on the density functional theory (DFT). Firstly, the MC, MC, MC (M = Cr, Mo, V, Fe) carbides models were established. Then, different interphases' lattice constants, formation enthalpy, binding energy and elastic modulus were calculated. The stability, hardness, ductility and anisotropy of each phase were finally analyzed. The results show that these phases are stable, and the stability is closely related to the electron loss ability of its metal elements. The stronger the electron loss ability of its metal elements, the more stable the formed phase. As for MC carbides, MoC has the largest bulk modulus and hardness. As for MC carbides, the Poisson's ratio of CrC is the smallest, and all phases except for CrC show toughness and ductility. The anisotropy of MC carbides is relatively poor.
本文基于密度泛函理论（DFT）采用第一性原理方法计算了钢中碳化物的稳定性、力学性能和电子结构。首先，建立了MC、MC、MC（M = Cr、Mo、V、Fe）碳化物模型。然后，计算了不同界面相的晶格常数、形成焓、结合能和弹性模量。最后分析了各相的稳定性、硬度、延展性和各向异性。结果表明，这些相是稳定的，且稳定性与其金属元素的电子损失能力密切相关。其金属元素的电子损失能力越强，形成的相越稳定。对于MC碳化物，MoC具有最大的体积模量和硬度。对于MC碳化物，CrC的泊松比最小，除CrC外的所有相均表现出韧性和延展性。MC碳化物的各向异性相对较差。
