On the Post-aging of the ARB Created AA1050\AA2024(pre-aged)\Al2O3 Composites

In this study, multilayered aluminum-based composites consisting of AA1050 (66.6 vol.%) and pre-aged AA2024 (33.4 vol.%) with a trace addition of Al₂O₃ nanoparticles (0.005 vol.%) were successfully fabricated using six cycles of accumulative roll bonding (ARB). The composites were subsequently subjected to post-aging at 110, 150, and 190 °C for varying durations (0–10 h) to optimize their microstructural and mechanical performance. A combination of optical microscopy, SEM, TEM, microhardness, and tensile testing was employed to evaluate the materials. The results revealed that ARB, in combination with minimal nanoparticle reinforcement, led to significant grain refinement. Remarkable enhancements in tensile strength (up to 220 MPa, a 215% increase over annealed AA1050) and ductility (14% total elongation) were achieved by ARB and post-aging. Notably, the presence of alumina nanoparticles not only delayed over-aging but also contributed to improve particle–matrix bonding and structural stability. This work introduces a practical approach for tailoring high-performance aluminum composites via hybrid strategies involving ARB, precipitation hardening, and nanoparticle-assisted microstructure refinement.