Effect of TiO2 and SiC Nanoparticles on the Microstructure and Mechanical Characteristics of AA7178 Metal Matrix Composite.

The purpose of this study was to explore the effect that stir casting has on a TiO2 and SiC nanoparticles reinforced aluminium matrix composite. In order to study the development of ceramic particle reinforced aluminium matrix composite, density, tensile strength, hardness, and fracture analyses were carried out. The scanning electron microscope (SEM) investigation showed that the reinforcement particles were distributed consistently throughout the aluminium matrix. Electron backscatter diffraction (EBSD) study revealed the grain refinement of composites on inclusion of nanoparticles. The results of the experiments revealed that addition of 3 weight percent TiO2 and SiC particles to AA7178 alloy led to an increase in both the maximum strength and the hardness properties but, the elongation percentage of the manufactured composites progressively deteriorated. From the fractured surface of tensile samples, a microstructural study showed that AA7178, AA7178/TiO2, and AA7178/SiC nanocomposites were showing both ductile and brittle behaviour because of micro-cutting and micro-voids. [ABSTRACT FROM AUTHOR]