| 引用本文: | 刚建伟,陈晓霞,唐伟能,陈荣石.高塑性Mg-Gd-Zn镁合金管材的组织和力学性能研究[J].材料科学与工艺,2013,21(3):87-94.DOI:10.11951/j.issn.1005-0299.20130314. |
| GANG Jian-wei,CHEN Xiao-xia,TANG Wei-neng,CHEN Rong-shi.Microstructure and mechanical properties of extruded Mg-3%Gd-1%Zn seamless tubes with high-ductility[J].Materials Science and Technology,2013,21(3):87-94.DOI:10.11951/j.issn.1005-0299.20130314. |
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| 摘要: |
| 为了制备高塑性镁合金无缝管材,将具有不同初始组织的Mg-3%Gd-1%Zn（质量分数/%,以下简称GZ31）合金空心锭在420~480 ℃挤压成无缝管材,采用金相显微镜、扫描电镜、X射线衍射分析和拉伸试验等表征了管材的组织和力学性能.结果表明：GZ31镁合金无缝管材较AZ31具有更弱的基面纤维织构；420 ℃一次挤压成形的GZ31管材由于组织中还存在粗大的原始晶粒,导致室温伸长率较低；440 ℃及以上挤压时得到完全再结晶组织,且随挤压温度升高,再结晶晶粒和第二相尺寸逐渐增大；经过一次挤压开坯后再在440 ℃二次挤压的无缝管材具有更细小的平均晶粒尺寸（约12 μm）,其室温伸长率高达35%,明显优于传统AZ31以及一次挤压成形的GZ31镁合金无缝管材. |
| 关键词: Mg-3%Gd-1%Zn镁合金 挤压 无缝管材 基面纤维织构 室温伸长率 |
| DOI：10.11951/j.issn.1005-0299.20130314 |
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| 基金项目:国家自然科学基金资助项目(51105350)；辽宁省博士启动基金(20111063). |
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| Microstructure and mechanical properties of extruded Mg-3%Gd-1%Zn seamless tubes with high-ductility |
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GANG Jian-wei1,CHEN Xiao-xia2,TANG Wei-neng2,CHEN Rong-shi2
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(1.Northeast Light Alloy Co., Ltd., Harbin 150060, China; 2.State Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China)
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| Abstract: |
| To manufacture high ductile magnesium alloy seamless tubes, Mg-3%Gd-1%Zn（wt%, called GZ31 bellow） alloy hollow billets with different initial microstructures were extruded as tubes at 420~480 ℃, and methods of optical microcopy (OM), scanning electron microscopy (SEM), X-ray diffraction and tensile tests were used to measure their microstructures and tensile room-temperature mechanical properties. Results show that the GZ31 tubes have a weaker basal plane fiber texture than AZ31. For one-step extrusion with casting billets, grains of tube extruded at 420 ℃ is finer, but a few coarse unrecrystallized grains still exist in microstructure,so that the tube has an inferior room temperature tensile elongation. The tubes extruded at 440 ℃ or higher temperatures have completely recrystallized microstructure, and as extrusion temperature increases, the sizes of recrystallized grains and second phases increase roughly. However, the tubes being secondarily extruded at 440 ℃ with first-extrusion billets have a finer grain size of 12 μm and the maximum room-temperature tensile elongation is of 35%, which is much better than that of conventional AZ31 alloy tubes and the one-step extruded GZ31 tubes. |
| Key words: Mg-3%Gd-1%Zn magnesium alloy extrusion seamless tube basal plane fiber texture room temperature tensile elongation |
