Microstructure and thermal properties of binary ceramic particle-reinforced aluminum matrix composites with SiC/LAS
Microstructure and thermal properties of binary ceramic particle-reinforced aluminum matrix composites with SiC/LAS
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DOI：
10.1007/s10853-021-06639-x
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发表时间：
2022-01
影响因子：
4.5
通讯作者：
S. Zhang;Q. Hou;Zhixiang Fu;Weili Zhang;Haiyun Jiang
中科院分区：
文献类型：
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作者：
S. Zhang;Q. Hou;Zhixiang Fu;Weili Zhang;Haiyun Jiang
多相颗粒增强策略有望有效地改善铝基复合材料的综合性能，如热物理性能和力学性能。本文采用粉末锻造工艺，成功地制备了β-eucridite(LAS)和碳化硅(SIC)颗粒增强的碳化硅复合材料。对复合材料的微观结构、界面相容性和热膨胀系数进行了评价。微观结构表征表明，碳化硅和硅烷的共同作用导致了不连续相的形成，具有微孔结构和无变形结构。这些复合材料的微孔结构有利于向内膨胀和消除内应力，有效地限制了铝合金的向外热膨胀行为。此外，SiC和LAS与Al颗粒具有紧密的界面结合，提高了界面结合强度。这些复合材料提供了实用和强大的拉应力，限制了铝基在加热下的热膨胀。随着LAS含量的增加，获得了细小的Al晶粒度(53.5 nm)和低的微观应变(0.4 × 10-4)。结果表明，在500℃时，复合材料的热膨胀系数为17.27 × 10-6K−1。实验值与混合体模型计算的理论值进行了比较，证实了复合材料与铝基体之间良好的界面结合对基体的膨胀起到了有效的抑制作用。
Multiphase particle-reinforced strategy shows promise for efficiently improving the comprehensive properties of aluminum matrix composites (AMCs) such as thermophysical and mechanical properties. In this work, AMC reinforced withβ-eucryptite (LAS), and silicon carbide (SiC) particles were successfully prepared via a powder forging process. The microstructure morphology, interface compatibility, and coefficient of thermal expansion (CTE) of these composites were evaluated. Microstructural characterization illustrated that the co-effect of SiC and LAS resulted in a discontinuous phase with a microporous and deformation-free structure. The microporous structure of these composites was conducive for inward expansion and the elimination of internal stress, effectively limiting the outward thermal expansion behavior of the Al alloys. Moreover, SiC and LAS exhibited tight interfacial bonds with the Al grains, enhancing interfacial bonding strength. These composites provided practical and robust tensile stress that limited the thermal expansion of the Al matrix under heating. A fine Al grain size (53.5 nm) and low micro-strain (0.4 × 10–4) were obtained with increasing LAS content. Consequently, the composites achieved a low CTE of 17.27 × 10–6K−1at 500 °C. The experimental CTE values were also compared with theoretical values calculated by a rule of mixture model to confirm that the excellent interfacial bonding between the LAS and SiC reinforcements and the Al matrix imposed an effective constraint on matrix expansion.Graphical abstract