1 The Effect of Carbon Nanotubes on Microstructure and Mechanical Properties of Al/TiH2/CNT Foam Precursor Produced via Continual Annealing and Roll-Bonding Process 1 Carbon nanotube (CNT)-reinforced aluminum matrix composites offer significant potential for lightweight, high-strength applications but face challenges in achieving uniform CNT dispersion. This study investigates the microstructural and mechanical enhancements of Al/TiH₂/CNT foam precursors fabricated through eight cycles of the Continual Annealing and Roll-Bonding (CAR) process. Aluminum strips (AA1050) were combined with 0.65 wt.% multi-walled CNTs and 0.75 wt.% TiH₂ as the foaming agent. Scanning electron microscopy (SEM) and field emission SEM (FESEM) were used to analyze CNT distribution, while tensile testing and Vickers microhardness assessed mechanical properties. Results revealed improved CNT dispersion with increasing CAR cycles, though minor agglomerations persisted due to van der Waals forces. The composite exhibited a 3.87-fold increase in microhardness (88.62 Vickers in the RD–TD plane) and a 3.49-fold increase in tensile strength (171 MPa) compared to annealed pure aluminum. These enhancements stem from effective load transfer and grain refinement facilitated by the CAR process. The findings highlight the CAR process's efficacy in producing Al/TiH₂/CNT precursors with superior mechanical properties, making them promising for structural applications requiring high strength-to-weight ratios. 1 8 Maryam Qasemi Department of Metallurgy and Materials Engineering, Engineering Faculty, Semnan University Iran maryam.qasemi3717@gmail.com Ali Habibolahzadeh Department of Metallurgy and Materials Engineering, Engineering Faculty, Semnan University Iran ahabibolahzadeh@semnan.ac.ir Metal foam composite Carbon nanotubes Accumulative Roll Bounding Microstructure Mechanical properties 1.Sarmah P, Gupta K. 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