You Zhiyong, Jin Shuaishuai, Han Peide, Jiang Aoxue, Sun Chunle
Shanxi Key laboratory of Magnesium matrix materials, College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan, 030024, People's Republic of China.
Sci Rep. 2025 Apr 7;15(1):11809. doi: 10.1038/s41598-025-96708-x.
This study systematically investigates the elastic anisotropy and thermodynamic properties of [Formula: see text] phase in Mg-Zn alloys through first-principles calculations combined with Debye-Grüneisen theory. Three critical intermetallic phases - monoclinic MgZn, cubic MgZn (C-MgZn), and hexagonal MgZn (H-MgZn) phases were comparatively analyzed. Electronic structure analysis reveals that C-MgZn and H-MgZn exhibit stronger chemical bonding stability compared to MgZn. Phonon dispersion characteristics demonstrate distinct vibrational patterns: C-MgZn and MgZn display enhanced phonon modes at both low and high frequency ranges, while H-MgZn shows predominant medium-frequency vibrational modes. Elastic anisotropy evaluation identifies MgZn as moderately anisotropic, H-MgZn as significantly anisotropic, and C-MgZn as nearly isotropic. Thermodynamic analysis predicts superior thermal stability for C-MgZn, evidenced by its highest Debye temperature (θ = 366 K), maximum sound velocity (v=3.468 m/s), and minimal Grüneisen parameter (γ = 0.641), correlating with its exceptional thermal conductivity. In contrast, MgZn exhibits the highest thermal expansion coefficient among the investigated phases. These findings establish fundamental structure-property relationships that advance the understanding of [Formula: see text] phase stabilization mechanisms, providing critical guidance for designing high-performance Mg-Zn alloys through phase engineering strategies.
本研究通过第一性原理计算结合德拜-格林艾森理论，系统地研究了镁锌合金中[化学式：见原文]相的弹性各向异性和热力学性质。对三种关键金属间相——单斜晶系的MgZn、立方晶系的MgZn（C-MgZn）和六方晶系的MgZn（H-MgZn）相进行了对比分析。电子结构分析表明，与MgZn相比，C-MgZn和H-MgZn表现出更强的化学键稳定性。声子色散特性表明了不同的振动模式：C-MgZn和MgZn在低频和高频范围内都表现出增强的声子模式，而H-MgZn则以中频振动模式为主。弹性各向异性评估表明，MgZn为中度各向异性，H-MgZn为显著各向异性，C-MgZn几乎为各向同性。热力学分析预测C-MgZn具有卓越的热稳定性，其最高德拜温度（θ = 366 K）、最大声速（v = 3.468 m/s）和最小格林艾森参数（γ = 0.641）证明了这一点，这与其出色的热导率相关。相比之下，MgZn在所研究的相中表现出最高的热膨胀系数。这些发现建立了基本的结构-性能关系，推进了对[化学式：见原文]相稳定机制的理解，为通过相工程策略设计高性能镁锌合金提供了关键指导。
