罕见双峰织构在提高AZ31镁合金板材冷轧成形性能中的作用  

Role of unusual double-peak texture in significantly enhancing cold rolling formability of AZ31 magnesium alloy sheet

作　　者：韩修柱[1] 胡励 贾东永 陈家明 周涛[2] 江树勇 田政 Xiu-zhu HAN;Li HU;Dong-yong JIA;Jia-ming CHEN;Tao ZHOU;Shu-yong JIANG;Zheng TIAN(Beijing Institute of Spacecraft System Engineering,Beijing 100094,China;College of Materials Science and Engineering,Chongqing University of Technology,Chongqing 400054,China;College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]北京空间飞行器总体设计部,北京100094 [2]重庆理工大学材料科学与工程学院,重庆400054 [3]太原理工大学材料科学与工程学院,太原030024

出　　处：《Transactions of Nonferrous Metals Society of China》2023年第8期2351-2364,共14页中国有色金属学报（英文版）

基　　金：supported by the Fund for Distinguished Young Scholars of China Academy of Space Technology(No.2021399);the National Natural Science Foundation of China(No.51805064);the Science and Technology Research Program of Chongqing Municipal Education Commission,China(No.KJQN202101141)。

摘　　要：对基极由板材法向向轧向偏离±40°的罕见双峰织构AZ31镁合金板材进行多道次冷轧实验研究。该板材由等径角轧制−连续弯曲−退火工艺制备。实验结果表明,该罕见双峰织构能大幅度提高板材的冷轧累积减薄率至39.2%,是传统强基面织构板材冷轧累积减薄率的2倍以上(18.3%)。金相和电子背散射衍射分析表明,该罕见双峰织构板材在冷轧过程中的显微组织及织构演化与传统强基面织构板材的区别显著。施密特因子(SF)分析表明,在冷轧过程中,基面<a>滑移和{1012}拉伸孪晶的SF值较大,而柱面<a>滑移和锥面<c+a>滑移的SF值较小。因此,基面<a>滑移和{1012}拉伸孪晶在该罕见双峰织构AZ31镁合金板材冷轧过程中将被大量激活来承载塑性应变,进而显著提高板材的冷轧成形性能。Multi-pass cold rolling experiments were performed on AZ31 magnesium alloy sheet with unusual double-peak texture,where basal poles tilt about±40°away from normal direction to rolling direction.This adopted sheet was fabricated by a novel technology of equal channel angular rolling and continuous bending process with subsequent annealing.Experimental results confirm that such an unusual double-peak texture contributes to a huge improvement of accumulated reduction up to 39.2%,which is over twice as much as that(18.3%)in sheet with strong basal texture.Optical microscopy and electron backscatter diffraction measurements demonstrate that the evolution of microstructure and texture in sheet with unusual double-peak texture is quite different from that in sheet with strong basal texture.Schmid factor(SF)analysis confirms that sheet with unusual double-peak texture possesses obviously large SF values for basal<a>slip and{1012}extension twin(ET)and remarkably small SF values for prismatic<a>slip and pyramidal<c+a>slip during cold rolling process.Therefore,basal<a>slip and{1012}ET will be activated more frequently in sheet with unusual double-peak texture to sustain plastic strain,leading to significant enhancement in cold rolling formability.

关 键 词：AZ31镁合金 非基面织构 冷轧工艺 显微组织演化 变形机制 

分 类 号：TG146.22[一般工业技术—材料科学与工程]