First-principles calculations of electronic, elastic and thermal properties of magnesium doped with alloying elements

Abstract

First-principles calculations have been carried out to investigate the effects of alloying elements (Zn, Li, Y and Sc) on the electronic structure, elastic and thermal properties of Mg solid solution. The calculated cohesive energies show that Mg-Sc has the highest structural stability. The calculations of the densities of states (DOS) and electronic charge density difference indicate that Mg-Y (Sc) alloys have very strong covalent bonding due to a very strong Mg p-Y(Sc) d hybridization. The bulk modulus B, shear modulus G, Young's modulus E and Poisson ratio ν are derived using Voigt-Reuss-Hill (VRH) approximation. The results show that all the alloys can exhibit ductile properties at 2.77 at% R, and Mg-Zn(Li) alloys have the better ductility and plasticity. In the end, the Debye temperature and isochoric heat capacity are also calculated and discussed.

Keywords

magnesium alloys / electronic structure / elastic properties / thermal properties / firstprinciples

References

[1] Potzies C, Kainer K U. Fatigue of Magnesium Alloys[J]. Adv. Eng. Mater., 2004, 6(5): 281-289.

[2] Chen Y, Cong K, Ma L, et al. Development of Ternary Mg Based Alloy for Soldering of AZ31B Magnesium Alloy[J]. Materials Science and Technology, 2014, 30: 977-981.

[3] Srinivasan A, Swaminathan J, Pillai U T. Effect of Combined Addition of Si and Sb on the Microstructure and Creep Properties of AZ91 Magnesium Alloy[J]. Materials Science and Engineering A, 2008, 485(1-2): 86-91.

[4] Jiang B, Qiu D, Zhang M X, et al. A New Approach to Grain Refinement of an Mg-Li-Al Cast Alloy[J]. J. Alloys Compd., 2010, 492(1-2): 95-98.

[5] Gao L, Chen R S, Han E H. Solid Solution Strengthening Behaviors in Binary Mg-Y Single Phase Alloys[J]. Journal of Alloys and Compound, 2009, 472: 234-240.

[6] Zhang J, Wang J, Qiu X, et al. Effect of Nd on the Microstructure, Mechanical Properties and Corrosion Behavior of Die-Cast Mg-4Al-Based Alloy[J]. Journal of Alloys and Compound, 2008, 464: 556-564.

[7] Gao L, Zhou J, Sun Z M, et al. Electronic Origin of the Anomalous Solid Solution Hardening of Y and Gd in Mg: A First-Principles Study[J]. Chinese Science Bulletin, 2011, 56(10): 1038-1042.

[8] Ganeshan S, Shang S L, Wang Y, et al. Effect of Alloying Elements on the Elastic Properties of Mg from First-Principles Calculations[J]. Acta Materialia, 2009, 57(13): 3876-3884.

[9] Chen K Y, Boyle K P. Elastic Properties, Thermal Expansion Coefficients and Electronic Structures of Mg and Mg-Based Alloys[J]. Metallurgical and Materials Transactions A, 2009, 40: 2751-2760.

[10] Yang F, Fan T, Tang B Y. Effects of Y and Zn Atoms on the Elastic Properties of Mg Solid Solution from First-Principles Calculations[J]. Physica Status Solidi B, 2011, 248(12): 2809-2815.

[11] Shi D M, Wen B, Melnik R. First-Principles Studies of Al-Ni Intermetallic Compounds[J]. J. Solid State Chem., 2009, 182(10): 2664-2669.

[12] Fagan S B, Mota R, Baierle R J. Stability Investigation and Thermal Behavior of a Hypothetical Silicon Nanotube[J]. J. Molecular Struct., 2001, 539: 101-106.

[13] Pack J D, Monkhors H J. Special Points for Brillouin-Zone Integrations[J]. Phys. Rev. B, 1977, 16: 1748-1749.

[14] Perdew J P, Burke K, Ernzerh M. Generalized Gradient Approximation Made Simple[J]. Phys. Rev. Lett., 1996, 77(18): 3865-3868.

[15] Monkhorst H J, Pack J D. Special Points for Brillouin Zone Integrations[J]. Phys. Rev. B, 1976, 13(12): 5188-5192.

[16] Fischer T H, Almlof J. General Methods for Geometry and Wave Function Optimization[J]. J. Phys. Chem., 1992, 96(24): 9768-9744.

[17] Raynor G V. The Lattice Spacing of the Primary Solid Solutions in Magnesium of the Metals of Group IIIB and Tin and Lead[J]. Proceedings of the Royal Society of London, 1942, 180: 107-121.

[18] Hardie D, Parkins R N. Lattice Spacing Relationships in Magnesium Solid Solutions[J]. Philosophical Magazine, 1959, 4: 815-825.

[19] Nayeb-Hashemi A A, Clark J B. Phase Diagrams of Binary Magnesium Alloys[M]. Metals Park: ASM International, 1988

[20] Huang Z W, Zhao Y H, Hou H, et al. Electronic Structural, Elastic Properties and Thermodynamics of Mg17Al12, Mg2Si and Al2Y Phases from First-Principles Calculations[J]. Physica B, 2012, 407: 1075-1081.

[21] Fu C L, Wang X D, Ye Y Y, et al. Phase Stability, Bonding Mechanism, and Elastic Constants of Mo5Si3 by First-Principles Calculation[J]. Intermetallics, 1999, 7(2): 179-184.

[22] Wazzan A R, Robinson L B. Elastic Constants of Magnesium-Lithium Alloys[J]. Physical Review, 1967, 155: 586-594.

[23] Hill R. The Elastic Behavior of a Crystalline Aggregate[J]. Proceeding of the Physical Society A, 1952, 65(5): 349-352.

[24] Hardie D. The Elastic Properties of Magnesium Solid Solutions[J]. Acta Metallurgica, 1971, 19: 719-723.

[25] Pugh S F. Relations between the Elastic Moduli and the Plastic Properties of Polycrystalline Pure Metals[J]. Philos. Mag., 1954, 45: 823-843.

[26] Pettifor D G. Theoretical Predictions of Structure and Related Properties of Intermetallics[J]. Materials Science and Technology, 1992, 8: 345-349.

[27] Mattesini M, Ahuja R, Johansson B. Cubic Hf₃N₄ and Zr₃N₄: A Class of Hard Materials[J]. Phys. Rev. B, 2003, 68(18): 184108-184112.

[28] Music D, Houben A, Dronskowski R, et al. Ab Initio Study of Ductility in M2AlC (M=Ti, V, Cr)[J]. Phys. Rev. B, 2007, 75(17): 174102

[29] Lofland S E, Hettinger J D, Harrell K, et al. Elastic and Electronic Properties of Select M2AX Phases[J]. Applied Physics Letters, 2008, 84: 508-510.

[30] Drulis M K, Czopnik A, Drulis H, et al. On the Heat Capacity of Ti3GeC2. Materials Science and Engineering B, 2005, 119(2): 159-163.