This study investigated how initial ingot thickness (400 mm vs. 520 mm) influences the microstructure and mechanical properties of Al–Zn–Mg–Cu alloys rolled to 80 mm. The combination of smaller initial thickness and lower total reduction (the 400-L route) results in lower dislocation density and a higher fraction of metastable η′ precipitates after T77 treatment. In contrast, the 520-L route, which involves a larger initial ingot thickness coupled with greater rolling reduction, yields higher dislocation density and a greater proportion of stable η phase. Texture also differs: the 400 mm ingot develops a strong S texture and high anisotropy, whereas the 520 mm ingot exhibits Brass texture and reduced anisotropy. Specifically, cross-rolling plus longitudinal rolling of the 520 mm ingot enhances recrystallization texture, giving a short-transverse yield strength of 528 MPa—within 6% of the longitudinal direction. This work offers valuable insights for controlling anisotropy in large 7xxx aluminum plates.

Nanocarbon materials, especially carbon nanotubes and graphene, have become preferred reinforcements for advanced aluminum (Al) matrix composites due to their excellent physical and mechanical properties. However, the strength-ductility trade-off in nanocarbon/Al composites remains a major obstacle to their engineering applications. Recent research has shown that heterogeneous design, aimed at promoting uniform strain distribution, enables nanocarbon/Al composites to maintain high strength while significantly improving their ductility. This work reviews recent research advances in heterostructured nanocarbon/Al composites, focusing on their fabrication, mechanical properties, fatigue damage behaviors, and hot processing characteristics. By addressing the critical scientific issues spanning from fabrication to service performance, this review aims to provide a theoretical foundation for developing high-performance heterostructured nanocarbon/Al composites and hasten their engineering applications.