Effect of Hot Rolling on the Properties of In Situ Ti-Aluminide and Alumina-Reinforced Aluminum Matrix Composite

In situ Ti-aluminide and alumina-reinforced aluminium matrix composite were prepared by the melt-cast route by adding 12 µm sized TiO₂ powder particles into molten aluminium at a temperature of 950°C. The effects of hot rolling temperature and percentage deformation on the microstructural architecture and mechanical properties (e.g., hardness and tensile strength) of aluminium matrix composite were studied in detail. Presence of different phases in the composite was identified with the aid of the Energy Dispersive X-Ray Analysis (EDXA). The percentages of reinforcements (Ti-aluminide and alumina) were estimated by image analysis. Fractographic investigations on the fractured surface of tensile specimens were also carried out with the aid of Scanning Electron Microscope (SEM). The composites exhibit fine distribution of reinforcements in the host matrix. It has been found that with the increase in rolling temperature and percentage deformation, hardness values and tensile strength of the composites improve significantly compared to the unreinforced aluminium.