长周期堆垛有序结构（LPSO结构）是镁合金中近年来新发现的一种新型增强结构。前期研究发现，增加了LPSO结构的Mg-RE-Zn（RE=Gd，Y）合金具有优异的高温力学性能，虽然其高温强化机制尚未阐明，但是可认为位于α-Mg基体中的栅栏状LPSO结构在合金高温变形过程中起到了显著的强化作用。课题组对LPSO结构的研究发现，其和α-Mg基体的主要界面（即原子密排面）完全共格，并且对非基面位错运动有明显阻碍作用。这种栅栏状LPSO结构在合金高温变形过程中与基体中的位错、孪晶间的作用机制，是否是像"栅栏"一样牢牢的阻碍位错在α-Mg基体中的运动均值得深入研究。基于对合金高温强化机制的研究，综合调控合金成分和热处理工艺、热加工方法和参数，获得对LPSO结构和稀土强化相有效调控的方法，探寻具有最佳性能的LPSO结构增强稀土镁合金制备方法及显微组织。

In recent years, a novel long period stacking ordered structure (LPSO structure) was found in Mg-RE-Zn alloys, which raised the attention of researchers all over the world immediately. Our studies shown, Mg-RE alloys containing LPSO structure exhibit excellent mechanical properties at elevated temperature. Although its strengthening mechanism has not been elucidated, it can be confirmed that LPSO structure plays a significant role in plastic deformation at elevated temperature. It is found the interface between barrier-liked LPSO structure and α-Mg matrix is fully coherent, and LPSO structure could restrict non-basal dislocation mobility at elevated temperatures.It is worthy of further study that the effect of barrier-liked LPSO structure on grain boundary, dislocation and twin during elevated temperature deformation process, and whether it is like a"barrier" to restrict dislocation mobility in α-Mg matrix. By controlling the alloy composition and fabrication process, heat treatment process (including solution treatment and aging treatment) and thermal deformation, the microstructure evolution of Mg-RE-Zn alloys will be systematically studied, as well as the formation mechanism, morphology, distribution and volume fraction of LPSO structure and RE strengthening phase. Based on our research, the alloy composition and fabrication process will be optimized.