摘要
通过第一性原理基于PAW方法研究了V_(2)AlX(X=C、N)相的结构、电子、声子和热力学性质。讨论了V_(2)AlX(X=C、N)相的结构和电子特性;利用晶格动力学的超晶胞方法计算了声子色散曲线,并通过准简谐近似预测高温下V_(2)AlX(X=C、N)相的热力学性质。结果表明:V_(2)AlC和V_(2)AlN具有金属性,且用N原子置换C原子后费米面处的态密度减低。V_(2)AlC和V_(2)AlN都是动力学稳定的。此外,还发现V_(2)AlN相的热力学性质比V_(2)AlC的更优异,且V_(2)AlN的体模量也高于V_(2)AlC。
The structure,electronic,phonon and thermodynamic properties of V_(2)AlX(X=C or N)were investigated by first-principles calculations using PAW method.The structural and electronic properties of the V_(2)AlX(X=C or N)were discussed.The supercell method of lattice dynamic was utilized to calculate the phonon dispersion curves,and the thermodynamic properties of the V_(2)AlX(X=C or N)phase at elevated temperatures were predicted by quasiharmonic approximation.The results show that V_(2)AlC and V_(2)AlN have metallicity and the replacement of N atoms for C atoms can result in the decrease in the DOS at Fermi level.Both the ternary MAX phases V_(2)AlC and V_(2)AlN are dynamically stable.Furthermore,it is found that the thermodynamic properties of V_(2)AlN are more excellent compared with that of V_(2)AlC phase,and the bulk modulus of V_(2)AlN is also higher than that of V_(2)AlC.
作者
黄大建
史沛然
法涛
HUANG Dajian;SHI Peiran;FA Tao(Key Laboratory of Surface Physics and Chemistry,Mianyang 621908,China)
出处
《热加工工艺》
北大核心
2024年第7期143-146,共4页
Hot Working Technology
基金
科学挑战计划项目(JCKY2016212A504)。
