不同应变率下热压缩双辊轧制Mg-5.51Zn-0.49Zr合金动态再结晶的位错机制（英文）

发布时间：2019-02-13 06:00

【摘要】：通过X射线衍射仪、光学显微镜和透射电镜研究Mg-5.51Zn-0.49Zr镁合金在热压缩实验中动态再结晶的位错机制。结果表明,当应变速率为1×10~(-3) s~(-1)时,由于位错攀移沿单一方向滑动,合金出现连续动态再结晶;当热压缩温度达到350°C、应变速率为1×10~(-2) s~(-1)时,由于位错发生滑移和攀移,合金出现连续动态再结晶;当热压缩温度达到400°C时,由于亚晶界弓出,合金出现不连续动态再结晶;当应变速率为1×100 s~(-1)时,合金出现连续动态再结晶是由于先导位错在堆积前发生攀移,导致位错在堆积过程中重新排列,形成位错差。一般来说,当应变速率增加时,位错攀移的主要影响机制由空位迁移转变为堆积前先导位错的压应力作用。
[Abstract]:The dynamic recrystallization mechanism of Mg-5.51Zn-0.49Zr magnesium alloy was investigated by X-ray diffraction, optical microscope and transmission electron microscope. The results show that when the strain rate is 1 脳 10 ~ (-3) s ~ (-1), continuous dynamic recrystallization occurs due to dislocation climbing sliding along a single direction. When the hot compression temperature reaches 350 掳C and the strain rate is 1 脳 10 ~ (-2) s ~ (-1), continuous dynamic recrystallization occurs due to dislocation slip and climbing. When the hot compression temperature reaches 400 掳C, the dynamic recrystallization of the alloy occurs due to the bowing out of the sub-grain boundary. When the strain rate is 1 脳 100s ~ (-1), the continuous dynamic recrystallization of the alloy is due to the upscaling of the leading dislocation before stacking, which leads to the rearrangement of the dislocation during the stacking process and the formation of dislocation difference. Generally speaking, when the strain rate increases, the main mechanism of dislocation climbing changes from the vacancy migration to the pressure-stress effect of the pre-stacking lead dislocation.
【作者单位】：中南大学有色金属材料科学与工程教育部重点实验室;中南大学材料科学与工程学院;Korea
【基金】：the financial support presented by Brain Pool Program of Korea and Core Technology R&D Program for the Development of High Performance Eco-friendly Structural Materials funded by the Korean Ministry of Commerce,Industry and Energy(Project No.10020072) 2011 Program of Ministry of Education of China
【分类号】：TG339;TG146.22

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