Zhao Tianshuo, Hu Yaobo, Pan Fusheng, He Bing, Guan Maosheng, Yuan Yuan, Tang Aitao
College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China.
National Engineering Research Center for Magnesium Alloys, Chongqing 400044, China.
Materials (Basel). 2019 Sep 23;12(19):3102. doi: 10.3390/ma12193102.
High performance Mg-6Al-3Sn-0.25Mn-Zn alloys ( = 0, 0.5, 1.0, 1.5, and 2.0 wt %) without rare earth were designed. The effects of different Zn contents on the microstructure and mechanical properties were systematically investigated. The addition of Zn obviously refines the as-cast alloys dendritic structure because of the increase in the number in the second phase. For the as-extruded alloys, an appropriate amount of Zn promotes complete recrystallization, thus increasing the grain size. As the Zn content increases, the texture gradually evolves into a typical strong basal texture, which means that the basal slip is difficult to initiate. Meanwhile, the addition of Zn promotes the precipitation of small-sized second phases, which can hinder the dislocation movement. The combination of texture strengthening and precipitation strengthening is the main reason for the improvement of alloys' strength.
设计了不含稀土的高性能Mg-6Al-3Sn-0.25Mn-Zn合金（=0、0.5、1.0、1.5和2.0 wt%）。系统研究了不同Zn含量对微观结构和力学性能的影响。由于第二相数量的增加，Zn的添加明显细化了铸态合金的枝晶结构。对于挤压态合金，适量的Zn促进了完全再结晶，从而增大了晶粒尺寸。随着Zn含量的增加，织构逐渐演变成典型的强基面织构，这意味着基面滑移难以启动。同时，Zn的添加促进了小尺寸第二相的析出，这可以阻碍位错运动。织构强化和析出强化的结合是合金强度提高的主要原因。
