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The effects of ordered carbon vacancies on stability and thermo-mechanical properties of V₈C₇ compared with VC.

ABSTRACT: The ordered non-stoichiometric V₈C₇ can form in the VC_y carbides 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 V₈C₇ are investigated in this paper by first-principle calculations combined with the quasi-harmonic approximation. The difference between the properties of VC and V₈C₇ can be obtained. We find that the V₈C₇ is 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 V₈C₇ and a simple way is proposed to characterize the anisotropy of lattice thermal conductivity based on the Cahill's model.

SUBMITTER: Chong X

PROVIDER: S-EPMC5034276 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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The effects of ordered carbon vacancies on stability and thermo-mechanical properties of V8C7 compared with VC.

Chong XiaoYu X Jiang YeHua Y Zhou Rong R Feng Jing J

Scientific reports 20160923

The ordered non-stoichiometric V8C7 can form in the VCy carbides 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 V8C7 are investigated in this paper by first-principle calculations combined ...[more]

PMID: 27659072

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