Scholarlink

<p>Heterogeneous deformation characteristics, microstructure evolution mechanisms, and hardness response of Mg–6.22Gd–3.04Y–0.49Zn–0.41Zr alloy with varied dislocation densities and only intragranular lamellar long-period stacking ordered (LPSO) phase were investigated through isothermal compression at 400 °C-10 s<sup>−1</sup>. Results indicated that heavily bimodal structures were obtained for the homogenization-treated (HOMT) and homogenization-deep cryogenic-treated (HDCT) samples after compression. Recrystallization nucleated at coarse grain boundaries, kinked bands, and lamellar shearing regions collaboratively refined the initial coarse grains. The lamellar LPSO phase directions transformed from random distribution to radial direction (RD) alignment with increased strain. Interestingly, although the HDCT sample had a higher proportion of recrystallization (~&#xa0;62.9&#xa0;pct), its average recrystallized grain size was smaller (~&#xa0;1.4 <i>μ</i>m). During the thermomechanical process, the higher initial cumulative dislocation energy in the HDCT sample promoted more pronounced recrystallization and enhanced Gd, Y, and Zn co-segregation at grain boundaries. Moreover, the higher proportion and finer grain size of recrystallization synergistically contributed to the increased hardness in the HDCT sample, with the highest hardness reaching approximately ~&#xa0;93 HV. It is further revealed that the continuous dynamic recrystallization (CDRX) mechanism was the dominant grain refinement mechanism for the HOMT and HDCT samples regardless of the initial cumulative dislocation energy.</p> Graphical Abstract <p></p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Influence of Intragranular Lamellar LPSO Phase on the Heterogeneous Plastic Deformation Characteristics and Hardening Response of As-Compressed Mg–Gd–Y–Zn–Zr Alloy

  • 期刊论文

  • 发表日期：

    2025年4月3日

查看全文
  • Dawei Meng,
  • Yan Xu,
  • Shengwei Su,
  • Bo Xu,
  • Jianbo Jia,
  • Junting Luo

摘要

Heterogeneous deformation characteristics, microstructure evolution mechanisms, and hardness response of Mg–6.22Gd–3.04Y–0.49Zn–0.41Zr alloy with varied dislocation densities and only intragranular lamellar long-period stacking ordered (LPSO) phase were investigated through isothermal compression at 400 °C-10 s−1. Results indicated that heavily bimodal structures were obtained for the homogenization-treated (HOMT) and homogenization-deep cryogenic-treated (HDCT) samples after compression. Recrystallization nucleated at coarse grain boundaries, kinked bands, and lamellar shearing regions collaboratively refined the initial coarse grains. The lamellar LPSO phase directions transformed from random distribution to radial direction (RD) alignment with increased strain. Interestingly, although the HDCT sample had a higher proportion of recrystallization (~ 62.9 pct), its average recrystallized grain size was smaller (~ 1.4 μm). During the thermomechanical process, the higher initial cumulative dislocation energy in the HDCT sample promoted more pronounced recrystallization and enhanced Gd, Y, and Zn co-segregation at grain boundaries. Moreover, the higher proportion and finer grain size of recrystallization synergistically contributed to the increased hardness in the HDCT sample, with the highest hardness reaching approximately ~ 93 HV. It is further revealed that the continuous dynamic recrystallization (CDRX) mechanism was the dominant grain refinement mechanism for the HOMT and HDCT samples regardless of the initial cumulative dislocation energy.

Graphical Abstract