An Al matrix composite reinforced with carbon nanotubes, Al3BC, and γ-Al2O3: Investigation of mechanical, thermal, and wear resistance properties

Carbon nanotubes (CNTs), with their exceptional theoretical modulus of elasticity, are among the most promising materials for reinforcing aluminum matrix composites. However, weak mechanical bonds formed between CNTs and the matrix, along with the formation of the brittle Al₄C₃ phase at the interface, often result in a deterioration of the composite's mechanical properties. In this study, a (CNTs+Al₃BC + Al₂O₃)/Al-Zn-Cu composite was fabricated through ball milling, sintering, hot extrusion, and solution treatment. The resulting composite exhibits Young's modulus of 98.1 GPa and ultimate tensile strength of 536 MPa, along with improved thermal properties and wear resistance. The primary strengthening mechanism includes the reinforcement provided by in-situ γ-Al₂O₃ and the CNTs encased by high-modulus in-situ generated Al₃BC particles. This research offers novel insights for the design of high-modulus, high-strength synergistic Al-CNTs composites.