Anisotropy of elastic and thermal properties of TMOs2 (TM = Sc, Y, Ti, Zr and Hf) from first-principles explorations. (11th October 2019)

• Record Type: Journal Article
• Authors: Qu, Deyi; Bao, Longke; Kong, Zhuangzhuang; Duan, Yonghua
• Is Part Of: Materials research express. Volume 6:Number 11(2019)
• Publication Date: 2019-10-11
• Subjects: first-principles calculations -- Os-based compounds -- anisotropic elasticity -- sound velocity; Materials science -- Research -- Periodicals; Materials science -- Periodicals; 620.11
• DOI: 10.1088/2053-1591/ab4ab9
• Languages: English
• ISSNs: 2053-1591

Abstract

Abstract: The thermal and elastic properties of the hexagonal TMOs2 (TM = Sc, Y, Ti, Zr and Hf) were obtained by the first-principles calculations. The single-crystal and polycrystalline elastic properties were obtained by the stress-strain method and the Voigt-Reuss-Hill approximations, respectively. Vickers hardness ( H V ) was evaluated using bulk and shear modulus, and the results indicated that these hexagonal TMOs2 are not potential superhard materials. The elastic anisotropy was described by elastic anisotropic indexes, and 3D surface constructions and their planar projections of elastic modulus. The order of elastic anisotropy is HfOs2 > ZrOs2 > TiOs2 > YOs2 > ScOs2 . Moreover, their sound velocity and Debye temperature were calculated. These TMOs2 compounds have anisotropy in sound velocity and Debye temperature along [100] and [001] directions.