title: The effects of ordered carbon vacancies on stability and thermo-mechanical properties of V8C7compared with VC.
abstract: The ordered non-stoichiometric V8C7can form in the VCycarbides by the disorder-order phase transformation. The intrusion of ordered carbon vacancies can affect their stability, mechanical, thermal and electronic properties. The relatively thermodynamic stability and mechanical properties at high temperature for the ordered stoichiometric VC and non-stoichiometric V8C7are investigated in this paper by first-principle calculations combined with the quasi-harmonic approximation. The difference between the properties of VC and V8C7can be obtained. We find that the V8C7is thermodynamic more stable than VC, but has weaker elastic heat resistance than VC. Moreover, the minimum thermal conductivity of VC is a little larger than V8C7and a simple way is proposed to characterize the anisotropy of lattice thermal conductivity based on the Cahill's model.
authors.affiliation: Faculty of Material Science and Engineering, Kunming University of Science and Technology, Kunming 650093, People's Republic of China.
authors.forename: XiaoYu
authors.initials: X
authors.lastname: Chong
authors.affiliation: Faculty of Material Science and Engineering, Kunming University of Science and Technology, Kunming 650093, People's Republic of China.
authors.forename: YeHua
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Faculty of Material Science and Engineering, Kunming University of Science and Technology, Kunming 650093, People's Republic of China.
authors.forename: Rong
authors.initials: R
authors.lastname: Zhou
authors.affiliation: Faculty of Material Science and Engineering, Kunming University of Science and Technology, Kunming 650093, People's Republic of China.
authors.forename: Jing
authors.initials: J
authors.lastname: Feng