(1. 湘潭大學(xué) 材料設(shè)備及制備技術(shù)湖南省重點(diǎn)實(shí)驗(yàn)室，湘潭 411105；
2. 湖南大學(xué) 材料科學(xué)與工程學(xué)院，長(zhǎng)沙 410082)
摘 要: 利用噴射共沉積−熱擠壓−軋制工藝制備SiCp/2024復(fù)合材料板材。研究該復(fù)合材料軋板熱處理后的顯微組織及力學(xué)性能，并確定其最佳的熱處理工藝條件。結(jié)果表明：軋制態(tài)復(fù)合材料組織細(xì)小均勻，晶粒尺寸為3~4 μm，SiC顆粒均勻分布在基體合金中；采用490 ℃、1 h固溶處理和170 ℃、8 h時(shí)效后，SiCp/2024復(fù)合材料軋板的抗拉強(qiáng)度、屈服強(qiáng)度和伸長(zhǎng)率分別為480 MPa、358 MPa和6.4%，基體合金中存在大量細(xì)小的第二相顆粒，為Al2MgCu及Al2Cu相；峰時(shí)效狀態(tài)時(shí)復(fù)合材料的布氏硬度值為228 HB，與軋板原始硬度相比較增幅達(dá)130%；噴射共沉積SiCp/2024復(fù)合材料軋板到達(dá)峰時(shí)效時(shí)間比鑄造2024鋁合金的短，這主要是因?yàn)閲娚涑练e基體合金內(nèi)細(xì)小均勻的晶粒組織、基體合金內(nèi)高密度的位錯(cuò)組態(tài)以及SiC顆粒的引入，均有利于沉淀相的提前析出。
關(guān)鍵字: 鋁基復(fù)合材料；噴射共沉積；熱處理；顯微組織；力學(xué)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
