Flow softening and dynamic recrystallization behavior of a Mg-Gd-Y-Nd-Zr alloy under elevated temperature compressions  

作　　者：Yiping WU Yuzhen JIA Sha Zhang Yu Liu Hanqing Xiong Gang Chen 

机构地区：[1]Department of Mechanical and Electrical Engineering,Changsha University,Changsha 410003,China [2]Bichamp Cutting Technology(Hunan)Co.,Ltd,Changsha 410200,China [3]College of Material Science and Engineering,Hunan University,Changsha Hunan 410082,China

出　　处：《Journal of Magnesium and Alloys》2023年第8期2891-2900,共10页镁合金学报（英文）

基　　金：This work was supported by the Changsha University Talent Introduction Project(50800-92808);the Excellent youth project of Hunan Provincial Department of Education(19B055,18B418,19C0156);the Natural Science Foundation of Hunan Province of China(2020JJ4645).

摘　　要：Flow softening behavior of a homogenized Mg-7Gd-4Y-1Nd-0.5Zr alloy under compression to a final strain of∼1.8 at elevated temperatures of 450∼550℃ and a constant strain rate of 2s^(−1) has been investigated by optical microscopy,scanning electron microscopy,electron back-scattered diffraction and transmission electron microscopy.The results show that true stress first rises to the peak point and then drops to the bottom value and increases again with further increasing strain at each temperature.Twinning dynamic recrystallization(DRX)and continuous DRX contribute to the formation of new fine grains at temperatures 450∼475℃ when the restoration is caused by both DRX and texture change due to extension twinning,resulting in the larger softening degrees compared with the softening effects owing to continuous DRX and discontinuous DRX at 500∼550℃ when twinning activation is suppressed.500℃ is the transition temperature denoting a significant decline in the contribution of twinning and TDRX to the strain with increasing temperature.The cuboid-shape phase exists in both homogenized and compressed samples,while the compositions are varied.

关 键 词：Mg-Gd-Y alloy Elevated temperature compression Flow softening Dynamic recrystallization 

分 类 号：TG146.22[一般工业技术—材料科学与工程]