(1. 湘潭大学 材料设备及制备技术湖南省重点实验室，湘潭 411105；
2. 湖南大学 材料科学与工程学院，长沙 410082)
摘 要: 利用喷射共沉积−热挤压−轧制工艺制备SiCp/2024复合材料板材。研究该复合材料轧板热处理后的显微组织及力学性能，并确定其最佳的热处理工艺条件。结果表明：轧制态复合材料组织细小均匀，晶粒尺寸为3~4 μm，SiC颗粒均匀分布在基体合金中；采用490 ℃、1 h固溶处理和170 ℃、8 h时效后，SiCp/2024复合材料轧板的抗拉强度、屈服强度和伸长率分别为480 MPa、358 MPa和6.4%，基体合金中存在大量细小的第二相颗粒，为Al2MgCu及Al2Cu相；峰时效状态时复合材料的布氏硬度值为228 HB，与轧板原始硬度相比较增幅达130%；喷射共沉积SiCp/2024复合材料轧板到达峰时效时间比铸造2024铝合金的短，这主要是因为喷射沉积基体合金内细小均匀的晶粒组织、基体合金内高密度的位错组态以及SiC颗粒的引入，均有利于沉淀相的提前析出。
关键字: 铝基复合材料；喷射共沉积；热处理；显微组织；力学性能
SiCp/2024 aluminum matrix composite
（1. Key Laboratory of Material Design and Technology of Hunan Province, Xiangtan University,
Xiangtan 411105, China;
2. College of Materials Science and Engineering, Hunan University, Changsha 410082, China）
Abstract:SiCp/2024 aluminum matrix composite sheets were fabricated by spray co-deposition, rolling and hot extrusion process. The microstructures and mechanical properties of the as-rolled composite sheets after heat treatment were investigated, and the optimum heat treatment process was determined. The results show that the fine and homogeneous grain structure is obtained in the as-rolled composite, the grains size is 3−4 μm, and the SiC particles distribute uniformly in the alloy matrix. Under the condition of 490 ℃, 1 h solid solution and 170 ℃, 8 h peak-aging heat treatment, the ultimate tensile strength, yield strength and elongation of the as-rolled composite sheets are 480 MPa, 358 MPa and 6.4%, respectively. There is a large amount of small precipitate strengthening phases in the alloy matrix at this stage, which are mainly Al2CuMg and CuAl2 phases. The Brinell hardness of as peak-aged composite is 228 HB, increased by 130% when compared with that of the original hardness. Compared with the as-cast 2024 aluminum alloy, the time required to achieve the peak aging for spray co-deposited SiCp/2024 composite is shorter, because the fine and homogeneous grain structures induced by the spray deposition increase dislocation density in the as-rolled composite after large deformation and the addition of SiC particles is advantageous for the precipitation of deposition phases.
Key words: aluminum matrix composite; spray co-deposition; heat treatment; microstructures; mechanical properties
