First-Principles Calculations on Structure, Elastic and Thermodynamic Properties of Al2X (X=Sc, Y) under Pressure

被引：30

作者：

Çiftci, Yasemin Öztekin ^{[1
]}

Çolakoĝlu, Kemal ^{[1
]}

Deligöz, Engin ^{[2
]}

Bayhan, Ülku ^{[3
]}

机构：

[1] Department of Physics, Gazi University, Teknikokullar, 06500, Ankara, Turkey

[2] Department of Physics, Aksaray University, 68100, Aksaray, Turkey

[3] Department of Physics, Mehmet Akif Ersoy University, Burdur, Turkey

来源：

Journal of Materials Science and Technology | 2012年 / 28卷 / 02期

关键词：

Calculations - Magnesium alloys - Lattice constants - Aluminum alloys - Anisotropy - Structural properties - Temperature - Specific heat - Copper alloys - Elastic moduli - Local density approximation - Scandium alloys - Thermal expansion;

D O I：

10.1016/S1005-0302(12)60036-X

中图分类号：

学科分类号：

摘要：

To understand deeply the structural, elastic and thermodynamic characteristics of Al2X (X = Sc, Y) compounds in C15 type (space number 227) Cu2Mg structure, we have performed ab-initio density functional theory within the local density approximation (LDA) and the generalized gradient approximation (GGA). The thermodynamic properties of the considered structures are obtained through the quasi-harmonic Debye model. We have presented the results on the basic physical parameters, such as the lattice constant, bulk modulus, pressure derivative of bulk modulus, second-order elastic constants, Zener anisotropy factor, Poisson's ratio, Young's modulus, and isotropic shear modulus. In order to gain further information, the pressure- and temperature-dependent behaviour of the volume, bulk modulus, thermal expansion coefficient, heat capacity, entropy, Debye temperature and Grüneisen parameter were also evaluated over a pressure range of 0-20 GPa for Al2Sc and 0-17 GPa for Al2Y compound and a wide temperature range of 0-2000 K for both compounds. The obtained results were compared with the other reported values. © 2012 The Chinese Society for Metals.

引用

页码：155 / 163