Chinese Journal of Applied Chemistry ›› 2026, Vol. 43 ›› Issue (1): 87-95.DOI: 10.19894/j.issn.1000-0518.250358

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Effect of Ag Content on Microstructure and Mechanical Properties of Mg-Gd Binary Alloys

Dong-Yue ZHAO1, HAO GU2, Qiang YANG1(), You LYU1, Xin QIU1, Valery-Konstantinovich SHELE3, Marina-Anatolyevna KRAVCHUK3   

  1. 1.China-Belarus Belt and Road Joint Laboratory on Advanced Materials and Manufacturing,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,China
    2.Key Laboratory of Superlight Material and Surface Technology,Ministry of Education,College of Material Science and Chemical Engineering,Harbin Engineering University,Harbin 150001,China
    3.Department of Mechanical Engineering Technology,Belarusian National Technical University,Minsk 220027,Belarus
  • Received:2025-09-17 Accepted:2025-11-17 Published:2026-01-01 Online:2026-01-26
  • Contact: Qiang YANG
  • About author:qiangyang@ciac.ac.cn
  • Supported by:
    the Scientific and Technological Developing Scheme of Jilin Province(YDZJ202301ZYTS538)

Abstract:

This study systematically investigates the influence of Ag content on the microstructure and mechanical properties of Mg-8Gd-0.5Zr-xAg(x%=0,0.5%,2%,5%) alloys fabricated via high-temperature extrusion with a large extrusion ratio, employing scanning electron microscopy (SEM), transmission electron microscopy (TEM), and tensile testing. The results demonstrate that the yield strength increases markedly with Ag addition, showing a remarkable improvement of 142 MPa in the Mg-8Gd-0.5Zr-5Ag alloy compared to the Ag-free counterpart. Microstructural analyses reveal that Ag not only refines grain size but also fundamentally alters the types of precipitates formed during extrusion. Electron backscatter diffraction (EBSD) indicates that the Mg-8Gd-0.5Zr-0Ag and Mg-8Gd-0.5Zr-0.5Ag alloys consist of partially recrystallized microstructures with elongated grains, whereas the Mg-8Gd-0.5Zr-2Ag and 5Ag alloys exhibit fully recrystallized structures, with the Mg-8Gd-0.5Zr-5Ag alloy achieving the smallest average grain size (1.3 μm). SEM-EDS analyses confirm an increase in the volume fraction of dynamic precipitates with higher Ag content. While the secondary phases in Mg-8Gd-0.5Zr-0Ag and Mg-8Gd-0.5Zr-0.5Ag alloys are identified as Mg5Gd (via TEM), the Mg-8Gd-0.5Zr-2Ag and Mg-8Gd-0.5Zr-5Ag alloys form Mg12Gd2Ag ternary phases. The superior yield strength of the 5%Ag alloy is attributed to the synergistic effects of precipitation strengthening and grain refinement.

Key words: Grain refinement, Precipitation strengthening, Mechanical properties, Microstructure evolution

CLC Number: