Abstract
Elastic and thermodynamic properties of the Al18Mg3M2 (M = Sc, Ti, Cr, Mn and Zr) phases with cubic structure were investigated by means of first-principles calculations within the framework of density functional theory. The three independent single-crystal elastic constants were calculated, showing that the Al18Mg3M2 phases are mechanically stable structures. Then the bulk modulus B, Young’s modulus E, shear modulus G and Poison’s ratio v were estimated for polycrystalline Al18Mg3M2 from the elastic constants by the Voigt–Reuss–Hill (VRH) approximation. The ductility of Al18Mg3M2 phases was analyzed, and Al18Mg3Sc2 possesses the greatest plasticity or ductility. The elastic anisotropy was also further discussed in details. The Young’s modulus for single crystal Al18Mg3M2 was the highest in the <111> direction. Finally, thermodynamic properties such as the Debye temperatures, the specific heat, and melting temperature for the Al18Mg3M2 phases were estimated from elastic properties..
Keywords
Al18Mg3M2 phases, First-principles calculations, Elastic properties, Themodynamic properties.
Citation
DU XIAOMING, DONG ZHEN BIAO, LI JING, WU ERDONG, Calculated elastic and thermodynamic properties of Al18Mg3M2 (M = Sc, Ti, Cr, Mn and Zr) phases, Optoelectronics and Advanced Materials - Rapid Communications, 9, 1-2, January-February 2015, pp.158-164 (2015).
Submitted at: Nov. 2, 2014
Accepted at: Jan. 21, 2015