中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 25 No. 3 March 2015 |
（1. Laboratory of Studies of Surfaces and Interfaces of Solids Materials, University of Setif 1, Setif 19000, Algeria;
2. Research Unit on Emerging Materials, University of Setif 1, Setif 19000, Algeria;
3. Department of Physics, University of Bordj Bou-Arreridj, 34000, Algeria;
4. Laboratory for Developing New Materials and their Characterization, Department of Physics,
Faculty of Science, University of Setif 1, Setif 19000, Algeria）
Abstract:The structural, electronic and elastic properties of the M2SiC phases were studied, where M are 3d, 4d, and 5d early transition metals. The valence electron concentration (VEC) effect of Ti, V, Cr, Zr, Nb, Mo, Hf, Ta and W on these properties was examined. The C44 saturates for a VEC value in surrounding of 8.5 for each serie. Hf-s, Ta-s and W-s electrons mainly contribute to the density of states at the Fermi level, and should be involved in the conduction properties. The distortion increases with increasing VEC and decreasing kc/ka factor except for the series M=Ti, V and Cr, where it is lower at the VEC value of 8.5 (it follows a parabolic variation). The M2SiC was characterized by a profound anisotropy for the shear planes and compressibility in the direction is higher than that along the cone except for W2SiC, where it is lower.
Key words: ternary carbides; ab initio calculation; crystal structural; electronic structure
