W掺杂Ti(C0.5N0.5)的电子结构及力学性能的理论分析
Theoretical Analysis of Electronic Structure and Mechanical Properties of W-Doped Ti(C0.5N0.5)
熊萧 1董定乾 2熊健松 1贺逢源 1陈鑫辉 1熊慧文 3张立3
作者信息
- 1. 四川轻化工大学机械工程学院,四川自贡 643000;自贡市希力数控工具有限公司,四川自贡 643000
- 2. 四川轻化工大学机械工程学院,四川自贡 643000;自贡市希力数控工具有限公司,四川自贡 643000;中南大学粉末冶金国家重点实验室,湖南长沙 410000
- 3. 中南大学粉末冶金国家重点实验室,湖南长沙 410000
- 折叠
摘要
采用密度泛函理论(DFT)的第一性原理方法对金属原子W掺杂Ti(C0.5N0.5)的晶格常数、弹性常数和电子结构以及电荷布居进行计算和分析,结果表明:W原子可稳定存在于(Ti1-xWx)(C0.5N0.5)中,但W原子的加入使得(Ti1-xWx)(C0.5N0.5)体系稳定性下降,增强了原子间的键能,且晶格因替换原子W与Ti的直径大小不同产生畸变,并伴随着W含量的增加会加剧晶格畸变和晶格常数失衡;由弹性常数计算结果表明,适当添加W原子能改善(Ti1-xWx)(C0.5N0.5)的抵抗外力变形的能力和硬度,同时可以降低晶体的脆性,且当x(W)=12%时,(Ti1-xWx)(C0.5N0.5)抵抗变形能力和硬度达到最佳,理论硬度HV提高了6%;电子结构计算结果显示,W原子掺杂后费米能级处态密度增加,增强了(Ti1-xWx)(C0.5N0.5)的导电性,且远高于Ti(C0.5N0.5)的导电性;通过差分电荷密度图发现,W原子掺杂替换Ti会与C原子形成极性共价键,可以改善(Ti1-xWx)(C0.5N0.5)的固有力学性能.
Abstract
The lattice constants,elastic constants,electronic structure,and charge distribution of Ti(C0.5N0.5)doped with metal W atoms were calculated and analyzed by using the first-principles method of density functional theory(DET).The results show that W atoms can exist in(Ti1-xWx)(C0.5N0.5)stably,but the addition of W atoms decreases the stability of the(Ti1-xWx)(C0.5N0.5)system,enhances the bonding energy among atoms,and distorts the lattice as Ti atoms and W atoms have different diameters.With the increase in W content,lattice distortion and lattice constant imbalance will be aggravated.The results of elastic constant calculation show that the appropriate addition of W atoms can improve the deformation resistance and hardness of(Ti1-xWx)(C0.5N0.5)and reduce the brittleness of the crystal.When x(W)= 12%,the deformation resistance and hardness of(Ti1-xWx)(C0.5N0.5)are the best.The theoretical hardness HV is increased by 6%.The calculation results of the electronic structure show that the state density increases at the Fermi level after doping W atoms,and the conductivity of(Ti1-xWx)(C0.5N0.5)is enhanced,which is much higher than that of Ti(C0.5N0.5).The charge difference density diagram shows that W atoms doping and replacing Ti atoms will form a polar covalent bond with C atoms,which can improve the inherent mechanical properties of(Ti1-xWx)and(C0.5N0.5).
关键词
TiCN/第一性原理/稳定性/力学性能/电子结构Key words
TiCN/first principles/stability/mechanical properties/electronic structure引用本文复制引用
基金项目
国家自然科学基金(52374371)
国家自然科学基金(52074365)
四川轻化工大学人才基金(2021RC18)
四川省科技计划(2022YFG0289)
过程装备与控制工程四川省高校重点实验室开放基金(GK202104)
过程装备与控制工程四川省高校重点实验室开放基金(GK202106)
出版年
2024
NETL
NSTL
万方数据