Microstructure and mechanical properties of extruded Mg-Gd-Y-Zn alloy with Mn or Zr addition
Microstructure and mechanical properties of extruded Mg-Gd-Y-Zn alloy with Mn or Zr addition
复制标题
添加Mn或Zr的挤压Mg-Gd-Y-Zn合金的显微组织和力学性能
DOI：
10.1007/s10853-019-03607-4
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发表时间：
2019-07-01
影响因子：
4.5
通讯作者：
Kamado, S.
中科院分区：
文献类型：
--
作者：
Xu, C.;Nakata, T.;Kamado, S.
研究了添加Mn或Zr的挤压态Mg-2Gd-1.2Y-0.5Zn(at.%)合金的组织和性能。结果表明，与添加Mn相比，添加Zr能更有效地细化均匀合金的组织，促进第二相的溶解。在400℃挤压后，添加了锰和锆的合金都呈现出双峰组织，包括具有随机取向的细小的动态再结晶(DRXed)晶粒和具有强烈的纤维织构的粗大的未动态再结晶(DRXed)晶粒。未经DRXed处理的晶内分布有细长周期堆积有序相和伽马析出物，纳米β相主要钉扎在DRXed晶界。而均质化后的加锰合金原始晶粒度较粗，导致其挤压后的DRX比较低，织构强度较强。两种挤压合金均获得了高强度、中等塑性和改善的屈服各向异性。添加Mn的合金具有更高的强度，极限抗拉强度为437 Mpa，0.2%的抗拉应力为381 Mpa，而断裂伸长率仅为4.7%，这主要是由于添加Mn的合金的DRX比低所致。
The microstructure and mechanical properties of the extruded Mg-2Gd-1.2Y-0.5Zn (at.%) alloy with Mn or Zr addition were investigated. The results show that Zr addition refines the microstructure of the homogenized alloy more efficiently and facilitates the dissolution of the secondary phases in comparison with Mn addition. After extrusion at 400 degrees C, both Mn and Zr added alloys exhibit bimodal microstructure comprising fine dynamically recrystallized (DRXed) grains with random orientations as well as coarse unDRXed grains with strong < 10 (1) over bar0 >//ED fiber texture. Thin long period stacking ordered phases and gamma precipitates distribute in the unDRXed grains and nano-sized beta phases mainly pin at the DRXed grain boundaries. While the coarse initial grain size of homogenized Mn added alloy leads to its lower DRX ratio and stronger texture intensity after extrusion with respect to Zr added alloy. High strength, moderate ductility and improved yield anisotropy are obtained in both extruded alloys. The Mn added alloy exhibits higher strength with ultimate tensile strength of 437 MPa, 0.2% tensile proof stress of 381 MPa but lower elongation to failure of 4.7% than Zr added alloy, which is mainly due to the lower DRX ratio of Mn added alloy.