Influence of Nano-sized Al₂O₃ Reinforcements on the Mechanical Behavior of the Al7075 Composites

Aims: Al7075 is a well-defined alloy for its excellent physical and mechanical behavior, such as high strength, toughness, and low density. To reach the expectations of the automobile and aerospace applications, the properties of Al7075 alloy have to be improved by reinforcing nano-sized Al₂O₃ particles. Objectives: Synthesis and characterization of the Al7075 alloy reinforced with Al₂O₃ nano particles for different structural engineering applications. Methods: In this present work, nano-sized Al₂O₃ particles were added and dispersed homogeneously using a stir casting technique. AA7076/Al₂O₃ composites were prepared by varying wt.% percent of Al₂O₃ reinforcement particles (0.75, 1, 1.25, 1.5. 1.75 and 2 wt.% (weight-percentage)). Results: The SEM micrographs reveal the homogeneous distribution of Al₂O₃ reinforcements along the grain boundaries of the Al7075 matrix material. The experimental test results showed that the addition of Al₂O₃ reinforcements and the mechanical properties of the Al7075/Al₂O₃ composite improved as compared to the Al7075 matrix material. Conclusion: The composite with 1.5 wt.% Al₂O₃ showed higher strength and hardness as compared to other reinforcements.