Microstructure and mechanical properties of Mg-Gd-Y-Zn-Mn alloy sheets processed by large-strain high-efficiency rolling
Microstructure and mechanical properties of Mg-Gd-Y-Zn-Mn alloy sheets processed by large-strain high-efficiency rolling
复制标题
大应变高效轧制Mg-Gd-Y-Zn-Mn合金板材的组织与力学性能
DOI：
10.1016/j.msea.2019.01.080
复制
发表时间：
2019-03-04
期刊：
影响因子：
6.4
通讯作者：
Pan, Fusheng
中科院分区：
文献类型：
--
作者：
Wang, Kui;Wang, Jingfeng;Pan, Fusheng
采用大应变高效轧制工艺制备了高性能Mg-8.8Gd-3.4Y-1 Zn-0.8Mn（wt%）合金板材。在400 ℃温度下，仅经过3道次和2道次的硬板轧制，就在难变形镁合金中引入了约87%和约91%的总压下量的大应变。观察了组织形貌和织构，并进行了沿着轧制方向（RD）和横向（TD）拉伸试验。大应变轧制使晶粒细化，LPSO相和β相均匀弥散分布，基体织构减弱。轧制后强度和延伸率的各向异性得到改善。轧制态试样的总压下量接近91%，表现出优异的力学性能，其极限抗拉强度（UTS）为434 MPa，拉伸屈服强度（TYS）为318 MPa，平行于TD的断裂伸长率（EL）为10.7%。通过定量分析晶粒取向与变形方式的关系，确定了塑性变形初期，基底滑移和棱柱滑移是主导变形方式，而锥体滑移和拉伸孪晶是补充变形方式。
The high-performance Mg-8.8Gd-3.4Y-1Zn-0.8Mn (wt%) alloy sheets were prepared by large-strain high-efficiency rolling process. The large strains with similar to 87% and similar to 91% total reduction were introduced in the hard-to deform Mg alloy by hard-plate rolling process at 400 degrees C for merely 3 and 2 rolling passes. The microstructural morphology and texture were examined, and the tensile tests were performed along rolling direction (RD) and transverse direction (TD). The large-strain rolling process brings in refined grains, homogeneous dispersive LPSO phase and beta phase and weakened basal texture. The anisotropy of the strength and elongation is improved after rolling. The as-rolled sample with similar to 91% total reduction exhibits excellent mechanical properties with ultimate tensile strength (UTS) of 434 MPa, tensile yield strength (TYS) of 318 MPa and elongation to failure (EL) of 10.7% parallel to the TD. By quantitating the relation between grain orientations and the deformation modes, it is confirmed that the basal slip and prismatic slip are the dominant deformation modes at the initial stage of plastic deformation, meanwhile the pyramidal slip and extension twinning are the complementary deformation modes.