Scholarlink

<p>The low strength and poor ductility of magnesium alloys at room temperature significantly hinder their applications. In this work, radial forging was employed to process extruded Mg-Gd-Zr alloy rods, achieving an excellent strength-ductility synergy. The mechanical properties of Mg-2Gd-<i>x</i>Zr alloys exhibited consistent variations with the gradient Zr content. After 8 forging passes, the Mg-2Gd-0.5Zr alloy demonstrated outstanding mechanical properties, with an ultimate tensile strength (UTS) of 302&#xa0;MPa and an elongation of 16.9%. During forging, abundant twin lamellae formed, and with increasing stress, these twins propagated throughout the parent grains. After 8 passes, the grain sizes of Mg-2Gd, Mg-2Gd-0.1Zr, and Mg-2Gd-0.5Zr alloys were significantly refined to 3.21&#xa0;μm, 2.86&#xa0;μm, and 2.83&#xa0;μm, respectively. The as-extruded three alloys all exhibited rare-earth textures, which subsequently evolved into basal fiber textures with orientations parallel to &lt; 10 <InlineEquation ID="IEq1"> <EquationSource Format="TEX">\(\:\stackrel{\text{-}}{\text{1}}\)</EquationSource> </InlineEquation>1&gt;. The addition of Zr weakened the texture, and the basal texture intensity decreased with increasing Zr content. By analyzing the relationship between the misorientation angle of the c-axis relative to the extrusion direction (ED) and the activation stress, the competitive behavior between slip/twinning and basal/non-basal slip within grains during multi-pass forging was investigated. The activation of non-basal slip was further demonstrated through statistical analysis of in-grain misorientation axes (IGMA). Compared to Mg-2Gd and Mg-2Gd-0.1Zr alloys, the superior ductility of Mg-2Gd-0.5Zr was attributed to its finer and more uniform grain structure, higher Schmid factor (SF) values for basal slip, and larger m’, along with significantly weakened texture. Quantitative analysis of strengthening mechanisms revealed that grain boundary strengthening was the primary contributor to the high yield strength (YS) in all three alloys. However, second-phase strengthening played a crucial role in the superior YS of Mg-2Gd-0.5Zr alloy compared to the other two alloys.</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

Effect of Gradient Zr Content on Microstructure and Mechanical Properties of Mg-Gd-Zr Alloys Under Radial Forging

  • 期刊论文

  • 发表日期：

    2025年10月17日

查看全文
  • Shengju Zhang,
  • Yaobo Hu,
  • Qiuyitong Zhang,
  • Yuanxiao Dai

摘要

The low strength and poor ductility of magnesium alloys at room temperature significantly hinder their applications. In this work, radial forging was employed to process extruded Mg-Gd-Zr alloy rods, achieving an excellent strength-ductility synergy. The mechanical properties of Mg-2Gd-xZr alloys exhibited consistent variations with the gradient Zr content. After 8 forging passes, the Mg-2Gd-0.5Zr alloy demonstrated outstanding mechanical properties, with an ultimate tensile strength (UTS) of 302 MPa and an elongation of 16.9%. During forging, abundant twin lamellae formed, and with increasing stress, these twins propagated throughout the parent grains. After 8 passes, the grain sizes of Mg-2Gd, Mg-2Gd-0.1Zr, and Mg-2Gd-0.5Zr alloys were significantly refined to 3.21 μm, 2.86 μm, and 2.83 μm, respectively. The as-extruded three alloys all exhibited rare-earth textures, which subsequently evolved into basal fiber textures with orientations parallel to < 10 \(\:\stackrel{\text{-}}{\text{1}}\) 1>. The addition of Zr weakened the texture, and the basal texture intensity decreased with increasing Zr content. By analyzing the relationship between the misorientation angle of the c-axis relative to the extrusion direction (ED) and the activation stress, the competitive behavior between slip/twinning and basal/non-basal slip within grains during multi-pass forging was investigated. The activation of non-basal slip was further demonstrated through statistical analysis of in-grain misorientation axes (IGMA). Compared to Mg-2Gd and Mg-2Gd-0.1Zr alloys, the superior ductility of Mg-2Gd-0.5Zr was attributed to its finer and more uniform grain structure, higher Schmid factor (SF) values for basal slip, and larger m’, along with significantly weakened texture. Quantitative analysis of strengthening mechanisms revealed that grain boundary strengthening was the primary contributor to the high yield strength (YS) in all three alloys. However, second-phase strengthening played a crucial role in the superior YS of Mg-2Gd-0.5Zr alloy compared to the other two alloys.