(华南理工大学 国家金属材料近净成形工程技术研究中心，广州 510640)
摘 要: 混杂颗粒增强铝基复合材料通过发挥各增强相的协同作用，提高其综合力学性能，具有单一颗粒增强铝基复合材料所不具备的优势。本文采用激光选区熔化(SLM)技术制备了TiC/SiC混杂颗粒增强AlSi10Mg复合材料。通过EBSD、SEM、TEM和拉伸试验研究了添加TiC、SiC颗粒对复合材料的显微组织和力学性能的影响。结果表明：TiC的加入，使(TiC+SiC)/AlSi10Mg复合材料的组织由粗大柱状晶转变为细小的等轴晶，铝基体平均粒径仅为4.27 μm。SiC与铝基体之间发生轻微的界面反应，生成少量棒状的Al4C3和Si，界面结合良好。SLM制备的(TiC+SiC)/AlSi10Mg复合材料具有优良的力学性能，其伸长率和抗拉强度分别为(9.7±0.4)%、(488±8) MPa，与SLM制备的AlSi10Mg合金相比，分别提高了19.8%和22.0%。TiC/SiC混杂增强铝基复合材料强度和塑性的提高是多种强化机制共同作用的结果，为采用SLM成形高性能铝基复合材料及其应用提供技术参考，具有重要的研究意义和应用价值。
关键字: 激光选区熔化；混杂颗粒；铝基复合材料；强化机制
（National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials, South China University of Technology, Guangzhou 510640, China）
Abstract:The hybrid particles reinforced aluminum matrix composite material has excellent mechanical properties, which a single nanoparticle reinforced aluminum matrix composite does not have, through the synergy of the reinforcement phases. In this study, the TiC/SiC hybrid particle reinforced AlSi10Mg composite material was prepared by selective laser melting (SLM) technology. The effects of TiC and SiC particles on microstructures and mechanical properties of composite materials were studied through EBSD, SEM, TEM and tensile tests. The results show that the addition of TiC changes the structure of the (TiC+SiC)/AlSi10Mg composite from coarse columnar grains to fine equiaxed grains, and the average grain size of the aluminum matrix is only 4.27 μm. The interface reaction between SiC and the aluminum matrix produces a small amount of rod-like Al4C3 and Si, and the interface is well bonded. The (TiC+SiC)/AlSi10Mg composite prepared by SLM has excellent mechanical properties. Its elongation and tensile strength are (9.7%±0.4)% and (488±8) MPa, respectively. Compared with those of AlSi10Mg alloy prepared by SLM, they are improved by 19.8% and 22.0%, respectively. The increment in strength and plasticity of TiC/SiC hybrid reinforced aluminum matrix composites is the result of multiple strengthening mechanisms. It provides a technical reference for the use of selective laser melting and forming of high-performance aluminum-based composite materials and their applications. It has important research significance and application value.
Key words: SLM; hybrid particles; aluminum matrix composites; strengthening mechanism
