铝合金熔体中初生Mg2Si形貌和尺寸的有效控制，是最终制备出满足实际服役条件需要的Mg2Si/Al复合材料的关键。在初生Mg2Si生长过程中，通过选择性添加微量元素，使其原子掺杂或吸附在Mg2Si晶格中或生长界面，可实现对Mg2Si最终形貌和尺寸的有效调控。因此，本项目拟以铝合金熔体中初生Mg2Si的生长形貌为研究对象，综合采用试验和计算机模拟相结合的手段，通过分析掺杂/吸附条件下的Mg2Si受控生长过程和内在生长机制，阐明典型元素晶格掺杂分布特性、表面吸附规律，明确其与Mg2Si生长的内在联系及影响机制；系统观察并分析Mg2Si不同生长阶段的二维/三维形貌特征，建立掺杂/吸附条件下Mg2Si相受控生长模型，进而揭示不同形貌间的相互转化机制，为微合金化组元的选择和高性能Mg2Si/Al复合材料的制备提供理论指导和技术支持，也为同类增强颗粒形貌控制提供借鉴和参考。

The effective control of morphology and size of primary Mg2Si in Al alloy melt is the key to fabricate Mg2Si/Al composites with meeting service condition need. During the growth process of primary Mg2Si, selective adding microelement atoms dope in the Mg2Si crystal lattice or adsorb on the growth interface of Mg2Si, which can effectively regulate the morphology and size of Mg2Si. Therefore, in this project, the growth morphology of primary Mg2Si in Al melt is chosen as the research object, and experimental analysis and computer simulation are adopted. The growth process and mechanism of Mg2Si under the condition of doping or adsorption is to be studied to illuminate the doping distribution characterization and adsorption law of typical elements, and clarify their influence on the growth of Mg2Si. Moreover, the doping/adsorption growth pattern of primary Mg2Si is to be established in terms of basic crystal growth theories and detailed observation of two- or three-dimensional morphology of Mg2Si phase, which subsequently reveals the morphological evolution of Mg2Si. These results can provide theoretical guidance and technical support for choosing microalloying elements and fabricating high-performance Mg2Si/Al composites. Further, it is of reference value for morphological control of similar reinforced particles.