Synthesis and Property Evaluation of Al7075-Al2O3 Composites

From the past few decades, the application of lightweight materials for automobiles and aerospace components has been improving fuel efficiency. However, the development of high wear resistant materials using monolithic materials such as aluminum and titanium alloys has reached a limit, which led to development of composite materials. Aluminum metal matrix composites are being used in place of cast iron and steel due to their lightweight and high strength. Particulate reinforced Al-MMCs exhibit higher mechanical and improved wear resistance properties.
This paper presents the research findings of the physical, mechanical and tribological properties of Al7075-Al₂O₃ composites. The composites of Al7075 containing 2-6 wt % Al₂O₃ were prepared using liquid metallurgy route. The experimental results showed that the density of the composites increases with increased Al₂O₃ content and further, agrees with the values obtained through the rule of mixtures. Hardness and tensile strength of Al7075-Al₂O₃ composites were found to increase with increased Al₂O₃ content in the matrix at the cost of reduced ductility. The wear properties of the composites containing Al₂O₃ were higher than that of the matrix material and further, the composite containing highest Al₂O₃ content exhibited superior wear resistance.