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Updated: Nov 20, 2025
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
The thermodynamic stability and mechanical properties of TiCN1-(0⩽x⩽ 1) compounds by cluster expansion method and
Yijie Chen1,2, Canhui Xu2, Shuanglin Hu2
1School of Materials Science and Engineering, Central South University, Changsha, 410083, People's Republic of China.
Abstract:
The thermodynamic stability and mechanical properties of titanium carbonitrides TiCN1-(0 ⩽x⩽ 1) are investigated by a combination of the universal cluster expansion method and the first-principles calculations. By considering the ordering of the N/C distributions on the anion sublattice sites of TiCN1-, a binary diagram of the heat of formation is constructed, and seven kinds of ground-state structures are predicted in the whole range of 0 ⩽x⩽ 1. These predicted ground-state TiCN1-structures are further proved to be dynamically and mechanically stable by examining their phonon dispersion spectra and elastic constants. Further studies indicate that the mechanical and thermodynamic properties of the ternary TiCN1-structures are generally better than those of the binary TiC or TiN, while the differences within the ternary systems are insignificant. The possible origin of the enhancement of the mechanical and thermodynamic properties of the predicted ground-state TiCN1-are discussed together with the electronic structures.
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