在 A356 铝合金中同时引入原位纳米颗粒(TiB2+ZrB2)和元素 Sb，通过纳米颗粒对基体的强化和 Sb 提高颗粒分散性所产生的协同作用来提高材料的力学性能。 结果表明，单独引入(TiB2+ZrB2)颗粒会细化 α-Al 基体，减小二次枝晶臂间距，但复合材料内部存在严重团聚现象，不利于性能的提高。 在此基础上引入 Sb，降低纳米颗粒与 Al 基体间 的界面能，纳米颗粒的团聚现象得到显著改善。 原位纳米(TiB2+ZrB2)颗粒和 Sb 的协同引入使复合材料的强度和塑性较A356 基体大幅提高，当(TiB2+ZrB2)和 Sb 的引入量分别为 3%和 0.6%(质量分数)时，铸态复合材料的抗拉强度、屈服强度和伸长率分别达到 216.4 MPa、119.7 MPa 和 7.2%，相较 A356 基体的性能分别提高 29.7%、23.5%、84.6%。

In this paper, in situ nanoparticles (TiB2+ZrB2) and Sb are introduced simultaneously into A356 aluminium alloy to improve the mechanical properties of the material through the synergistic effect arising from the reinforcement of the matrix by the nanoparticles and the enhancement of particle dispersion by Sb. The introduction of (TiB2+ZrB2) particles alone has been shown to refine the α-Al matrix and reduce the secondary dendrite arm spacing. However, the presence of heavy agglomerates in composites can affect their performance. To address this issue, Sb is introduced to reduce the interfacial energy between the nanoparticles and the Al matrix, leading to a significant improvement in the agglomeration phenomenon of the nanoparticles. The synergistic introduction of in situ (TiB2+ZrB2) nanoparticles and Sb results in a substantial increase in the strength and plasticity of the composites compared to those of the A356 matrix. The tensile strength, yield strength, and elongation of the as-cast composites reach 216.4 MPa, 119.7 MPa, and 7.2%, respectively, when the introductions of (TiB2+ZrB2) and Sb are 3 wt. % and 0.6 wt. %, respectively, which are 29.7%, 23.5%, and 84.6% greater than the performance of the A356 matrix, respectively.