In this investigation, microstructure, grains morphology, mechanical and tribological characteristics of the Al7075/SiC, Al7075/GNPs and Al7075/Al2O3 specimens were examined. Al7075-based composite and nanocomposite reinforced with hard ceramic micro- and nano-sized particles (2 wt%) were prepared by employing the associated effort of reinforcement dispersion and ultrasonic-assisted melt-stirring approach. Ultrasonic liquid processing and ball-milling techniques were adopted as a dispersion approach by which an effort has been made to break the clusters of the nanoparticles. The microstructure and grains of the composite and nanocomposite specimens were examined via optical microscopy and scanning electron microscopy apparatus and depict grain refinement and good dispersion of the micro- and nano-sized ceramic reinforcing particles. Further, the mechanical properties such as hardness and ultimate tensile strength of the Al7075-based specimens were investigated. The dry-sliding wear characteristics of the Al7075-based MMCs were examined via Pin-on-disc apparatus under different loading conditions (10 N, 15 N, 20 N), sliding velocities (0.75 m/s and1.5 m/s) and for a constant sliding distance (1000 m) in the ambient environment. The influence of load, sliding velocity and reinforcements on the dry-sliding wear characteristics of ultrasonic-assisted stir-casted Al7075-based metal matrix composites (MMCs) subjected to numerous loads was examined under ambient conditions. The results obtained for various wear parameters show a significant effect of load and sliding velocity on the wear characteristics of the Al7075-based MMCs. The results revealed that the Al7075/Al2O3 composite exhibits the highest wear resistance over the Al7075/SiC and Al7075/Graphene composites. [ABSTRACT FROM AUTHOR]