Effects of solid-state interfacial reaction on the mechanical properties of carbon nanotubes reinforced aluminum matrix composites with heterogeneous structure

• Published in: Materials characterization Vol. 194; p. 112447
• Main Authors: Xu, Z.Y., Li, C.J., Peng, Y.Z., You, X., Gao, P., Liu, Y.C., Tao, J.M., Bao, R., Wang, Y.R., Yi, J.H.
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.12.2022
• Subjects: Aluminum matrix composite (AMC); Carbon nanotubes (CNTs); Interfacial reaction; Mechanical properties; Carbon nanotubes (CNTs); Mechanical properties; Interfacial reaction; Aluminum matrix composite (AMC)
• ISSN: 1044-5803; 1873-4189
• DOI: 10.1016/j.matchar.2022.112447

To overcome strength-ductility trade-off in carbon nanotubes (CNTs) reinforced Al matrix composites, we developed a novel and controllable strategy via a combination of different length of CNTs and fine/coarse-grained matrices. Microstructure analysis showed that Al4C3 nanorods about 100 nm were distributed in the fine grain zone (FGZ), while CNTs of micron length were distributed in the coarse grain zone (CGZ). Different sizes of reinforcements play different strengthening roles, and the bimodal grains can effectively coordinate deformation, thereby achieving a good combination of strength and ductility. Heat treatment does not affect the microstructure of the FGZ, but significantly affect the CNT/Al interface bonding in the CGZ. Heat treatment at an appropriate temperature can further improve the strength of the composite by improving the interface bonding. When the heat treatment temperature is too high, the coarsening of Al4C3 in CGZ will deteriorate the mechanical properties of the composite. •Balancing strength and ductility of CNTs/Al composites by heterostructure design.•CNTs of different lengths play a synergistic role in strengthening.•The influence of solid-interface reaction on the mechanical properties was investigated.