The Effect of Annealing on the Microstructure and Properties of Ultralow-Temperature Rolled Mg–2Y–0.6Nd–0.6Zr Alloy
The Effect of Annealing on the Microstructure and Properties of Ultralow-Temperature Rolled Mg–2Y–0.6Nd–0.6Zr Alloy
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DOI：
10.3390/met11020315
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发表时间：
2021-02
期刊：
影响因子：
2.9
通讯作者：
Hongming Yu;Wei Li;Yun Tan;Yuanbiao Tan
中科院分区：
文献类型：
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作者：
Hongming Yu;Wei Li;Yun Tan;Yuanbiao Tan
Mg-2Y-0.6Nd-0.6Zr合金首先采用等道角压变形（ECAP），然后在超低温条件下（液氮浸泡）轧制变形，最后退火。利用光学显微镜（OM）、电子背散射衍射技术（EBSD）和透射电镜（TEM）分析了合金在超低温和不同退火条件下的多尺度组织演变和力学性能的变化。结果表明：经ECAP处理的合金晶粒细小，在超低温轧制过程中形成大量细小孪晶，促进了合金硬度和强度的提高，并提供了许多优先形核位；退火更容易诱导再结晶，提高再结晶成核率。合金经超低温轧制后产生的孪晶界和退火后形成的均匀细晶粒使合金具有优异的强度和塑性。超低温轧制后形成的孪晶主要为{101-2}拉伸孪晶。经350℃退火10 min后，合金的抗拉强度为186.15 MPa，伸长率为29%，综合力学性能良好。
Mg–2Y–0.6Nd–0.6Zr alloy was first deformed by equal channel angular pressing (ECAP), then rolled and deformed under ultralow temperature conditions (liquid nitrogen immersion), and finally annealed. Optical microscopy (OM), electron backscatter diffraction technology (EBSD), and transmission electron microscopy (TEM) were used to analyze the evolution of the multiscale microstructure and changes in the mechanical properties of the alloy under ultralow temperatures and various annealing conditions. The results showed that the alloy treated with ECAP obtained fine grains, and a large number of fine twins were formed during the ultralow-temperature rolling process, which promoted the improvement of its hardness and strength and provided numerous preferential nucleation sites. The annealing made it easier to induce recrystallization and improve the recrystallization nucleation rate. The twin boundary produced by the alloy after ultralow-temperature rolling and the uniform fine grains formed by annealing resulted in excellent strength and plasticity of the alloy. The twins formed after rolling under ultralow temperatures were mainly {101-2} tensile twins. The alloy had comprehensive mechanical properties with a tensile strength of 186.15 MPa and an elongation of 29% after annealing at 350 °C for 10 min.