摘要
基于第一性原理方法,探索M-Al-N(M=Ti,Zr,Hf)结构的稳定性,计算其力学性质.计算M-Al-N化合物的能量,发现除实验已知的结构Ti2AlN和Ti4AlN3、Zr2AlN、Hf2AlN外,还存在两种新的热力学稳定结构Zr4AlN3、Hf4AlN3.弹性常数和声子谱的计算,表明这两个结构是力学稳定和晶格动力学稳定的.计算M2AlN和M4AlN3的力学性质,发现它们具有高的体模量、剪切模量、弹性模量、维氏硬度等;分析其力学性质随组分比例、组成元素的变化规律,为该类材料的选择和应用提供理论依据.最后计算M2AlN和M4AlN3的电子态密度和分态密度、电子密度分布、Mulliken群分析等.
Based on first-principles method,structural stability of M-Al-N(M=Ti,Zr,Hf)was investigated and mechanical properties were calculated.Firstly,enthalpies of M-Al-N compounds were calculated,and M2AlN and M4AlN3 were found to be thermodynamically stable.Except for experimental structures Ti2AlN,Ti4AlN3,Zr2AlN and Hf2AlN,two stable structures Zr4AlN3 and Hf4AlN3 were found.Mechanically and dynamically stable were verified by calculation of elastic constants and phonon spectrum.Mechanical properties of M2AlN and M4AlN3 were calculated.It was found that they had high bulk modulus,shear modulus,elastic modulus,Vickers hardness and brittleness.Variation of mechanical properties of M-Al-N compounds with composition was analyzed,which provided theoretical basis for selection and application of this kind of materials.At last,electron density of states and partial DOS,electron density,Mulliken population analysis of M-Al-N(M=Ti,Zr,Hf)compounds were calculated.
作者
彭军辉
PENG Junhui(Department of Materials Engineering,Taiyuan Institute of Technology,Taiyuan,Shanxi 030008,China)
出处
《计算物理》
EI
CSCD
北大核心
2020年第5期603-611,共9页
Chinese Journal of Computational Physics
基金
山西省材料科学与工程重点扶持学科基金资助项目
