Molecular dynamics simulation of thermodynamic properties of Mg-Cu alloys

doi:10.12028/j.issn.2095-4239.2019.0019

Abstract

Abstract: The Mg-Cu alloys were studied using the molecular dynamics approach with an embedded atom method (EAM). The thermal properties and microstructure of different Mg-Cu alloys were investigated. The melting temperature and enthalpy were studied based on the energy-temperature curve and the C_p-temperature curve. The results showed that, with the growth of Cu content, the melting point of Mg-Cu alloys decreased frst and then increased, and the melting enthalpy increased first and then decreased. With the increase of Cu content, the density and specific heat capacity decreased, and the thermal conductivity increased. We simulated the microstructure of Mg-Cu alloy at the room temperature. The results showed that the interaction between different atoms in Mg-Cu alloy was stronger, which was benefcial to the formation of α+Mg₂Cu eutectic structure. The simulation results also confrmed that the α+Mg₂Cu eutectic was a major factor affecting the melting enthalpy and thermal conductivity of the Mg-Cu alloy.

Key words: binary alloy, metal phase transition, thermodynamic property, molecular dynamics

CLC Number:

TK11
TK02

YU Jiapeng, CHENG Xiaomin, LI Yuanyuan, LI Bei, XU Hong. Molecular dynamics simulation of thermodynamic properties of Mg-Cu alloys[J]. Energy Storage Science and Technology, 2019, 8(4): 772-777.

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