Carbon nanotube-reinforced aluminum matrix composites enhanced by grain refinement and in situ precipitation

Carbon nanotubes-reinforced aluminum matrix (CNTs/Al) composites possess wide application prospects in many fields, and how to achieve a high performance is always a research hot spot. In this study, a novel high-performance Al matrix nanocomposite reinforced with short CNTs and in situ Al4C3 nanorods was fabricated by combining ball milling and hot extrusion, and they exhibit excellent comprehensive mechanical properties. The 2 wt% CNTs/Al composite reached a tensile strength of 312 MP and an elongation of 15.8%, showing an 102% strength improvement compared with the pure aluminum prepared by the same process. The remarkable improvement of the mechanical properties originates from the synergistical enhancement of fine-grained strengthening and dispersion strengthening of in situ Al4C3 nanorods and short CNTs.