Study Analysis of Diffusion in MgZnAl Alloy Using Molecular Dynamics Simulation

Muhammad Ilyas Ghifari, Rizal Arifin, Yoyok Winardi.
Mechanical Engineering Study Program, Faculty of Engineering, Universitas Muhammadiyah Ponorogo
Ponorogo, Indonesia

e-mail: [ilyasghifari29@gmail.com](mailto:ilyasghifari29@gmail.com)

Abstract

The magnesium-aluminum alloy MgZnAl is a lightweight material that is widely developed in the automotive and manufacturing industries due to its low density and good mechanical properties. However, information regarding the atomic diffusion mechanism in the Mg₂₅Zn₂₅Al₅₀ composition remains limited, even though the diffusion characteristics of each element play an important role in the stability and performance of materials at high temperatures. This study aims to analyze the diffusion mechanism, atomic mobility, and diffusion coefficients in the Mg₂₅Zn₂₅Al₅₀ alloy using the Molecular Dynamics (MD) method. The alloy model was constructed using Avogadro and simulated using LAMMPS with the Modified Embedded Atom Method (MEAM) potential under the NVT ensemble at temperatures of 1000 K, 1100 K, 1200 K, and 1300 K. The simulation results were analyzed using OVITO to obtain the Mean Square Displacement (MSD), atomic diffusion visualization, and diffusion coefficients based on the Einstein equation. The results show that the crystal model has a lattice parameter deviation of less than 1% compared with reference data. Increasing temperature resulted in an increase in the MSD and diffusion coefficients of all elements, indicating that atomic mobility increased with temperature. The diffusion coefficient of Mg atoms increased from 0.300 × 10⁻⁹ m²/s to 2.811 × 10⁻⁹ m²/s, Zn atoms from 0.147 × 10⁻⁹ m²/s to 1.243 × 10⁻⁹ m²/s, and Al atoms from 1.545 × 10⁻⁹ m²/s to 2.883 × 10⁻⁹ m²/s over the temperature range of 1000–1300 K. This study is expected to serve as a reference for the development of simulation-based MgZnAl alloys to support lightweight material applications in the automotive and manufacturing industries.

Keywords: Molecular Dynamics, MgZnAl, Mean Square Displacement, Diffusion Coefficient.