采用热等静压和热挤压工艺制备单一粒径（50，25，15，10 μm）和混合粒径（10 μm+25 μm）SiC_p/2024铝合金复合材料，并进行T4处理，研究了SiC粒径对复合材料显微组织和力学性能的影响；对性能最优的复合材料进行T6处理，研究了其组织和力学性能的变化。结果表明：添加单一粒径SiC时，随着粒径的减小，SiC颗粒在基体中的分布更加均匀，复合材料的抗拉强度增大，屈服强度、弹性模量、断后伸长率和布氏硬度变化不大；添加混合粒径SiC时，小粒径SiC会分布在大粒径颗粒周围，导致组织均匀性下降；混合粒径复合材料的抗拉强度介于对应单一粒径复合材料的之间，屈服强度略高于相应单一粒径复合材料的；粒径10 μm SiC_p/2024铝合金复合材料的性能较佳，再经T6处理后，其抗拉强度、屈服强度和布氏硬度进一步提高。

SiC_p/2024 aluminum alloy composite, strengthened with single particle size (50, 25, 15, 10 μm) and mixed particle size (10 μm+25 μm) SiC, was prepared by hot isostatic pressing and hot extrusion, and then was T4 treated. Effect of SiC particle size on microstructure and mechanical properties of the composite was studied. T6 treatment was conducted on the composite having the best performance, and the change of the microstructure and mechanical properties was investigated. The results show that under condition of single particle size, with decreasing particle size, the SiC particles distributed more evenly in the matrix; the tensile strength of the composite increased while the yield strength, elasticity modulus, percentage elongation after fracture and Brinell hardness changed little. Under condition of mixed particle size, the small-size SiC particles gathered aroud the large-size particles, leading to the decrease of structure uniformity. The tensile strength of the mixed particle size composite was between those of the corresponding single particle size composites, and the yield strength was slightly higher than those of the corresponding single particle size composites. The 10 μm size SiC_p/2024 aluminum alloy composite had relatively good performance, and after T6 treatment, the tensile strength, yield strength and Brinell hardness were further improved.