目前关于长周期堆垛（LPSO）相及Mg/LPSO双相合金的塑性变形行为和强化机制的研究较少，且主要停留在定性分析层面。本项目结合使用弹粘塑性自洽（EVPSC）模型和原位同步辐射测试，对LPSO相及Mg/LPSO双相合金的塑性变形行为和强化机制进行深入的定量研究。本项目首先建立了LPSO相特有的扭折变形机制的数值模型，并将其引入EVPSC模型中。然后使用EVPSC模型和原位同步辐射测试对具有不同显微组织的LPSO相及Mg/LPSO双相合金进行研究，揭示合金在加载过程中启动的塑性变形机制及其启动量，以及显微组织对塑性变形行为的影响，并建立LPSO相中各种塑性变形机制的启动应力与扭折数量及扭折带旋转角的定量关系。研究结果对于揭示Mg/LPSO双相合金强度和塑性的内在机制具有重要的意义。

The plastic deformation behavior and strengthening mechanism of long period stacking ordered (LPSO) phase and Mg/LPSO two-phase alloy have been rarely explored, only with a few studies mainly focusing on the qualitative analysis. This project combines elastic visco-plastic self-consistent (EVPSC) model and in-situ synchrotron diffraction measurement to quantitatively study the plastic deformation behavior and strengthening mechanism of LPSO phase and Mg/LPSO two-phase alloy. Firstly, this project introduces kinking mechanism, which is a unique deformation mechanism in LPSO phase, into the EVPSC model. Then the EVPSC model and in-situ synchrotron diffraction measurement are used for the study of LPSO phase and Mg/LPSO two-phase alloy, aiming to reveal the activation of deformation mechanisms and their specific contribution to plasticity under loading and establish the quantitative relationship between the activation stress of individual deformation mechanisms in the LPSO phase and the quantity and rotation angle of kink bands. The results of this project are of great importance to revealing the underlying mechanism controlling the strength and ductility of Mg/LPSO two-phase alloy.