颗粒增强铝硅复合材料具有良好的力学性能和热学性能，可应用于航空航天和汽车等领域，但是内生法制备纳米颗粒强化铝硅合金中增强相颗粒存在一定程度的团簇，并且在制备加工过程中会存在孔洞、夹杂等缺陷，严重损害材料的性能，因此急需开发改善颗粒分布、净化熔体的方法。 本文结合超声振动研究了重熔处理对 2%TiB2/Al-Si(质量分数)复合材料显微组织和抗弯强度的影响。 结果表明，重熔过程中引入高能超声振动可以有效破碎颗粒团簇，提高纳米颗粒的分布均匀性。重熔对初生 Si 的长大有抑制作用，750 ℃重熔后初生 Si 的平均尺寸与重熔前相比减小了 18.8%。TiB2/Al-20Si 复合 材 料 的 抗 弯 性 能 达 到 了 304 MPa， 比重 熔 前 提 高 了 14.6% 。 TiB2/Al-20Si 复合 材 料 的 热 导 率 为169.4 W/(m·K)，比重熔前提高了 4.8%。

Particle-reinforced Al-Si composites exhibit excellent mechanical and thermal properties, making them suitable for aerospace and automotive applications. However, in situ synthesized nanoparticle-strengthened Al-Si alloys often face challenges such as particle clustering and the formation of defects such as pores and inclusions during fabrication and processing, which significantly deteriorate material performance. Consequently, methods for improving particle distribution and melt purification are urgently needed. On this basis, the influence of remelting combined with ultrasonic vibration on the microstructure and flexural strength of 2 wt.% TiB2/Al-Si composites was investigated. The results demonstrate that the introduction of high-energy ultrasonic vibration during remelting effectively breaks out particle agglomerations and enhances the uniform distribution of nanoparticles. Additionally, remelting suppresses the coarsening of primary Si, reducing its average size by 18.8% after remelting at 750 ℃ compared with the as-cast state. The flexural strength of the TiB2/Al-20Si composite reaches 304 MPa, representing a 14.6% improvement over that of the nonremelted material. The thermal conductivity of the TiB2/Al-20Si composite reaches 169.4 W/(m·K), representing a 4.8% increase compared with its state before remelting.