Wear Characterization of Aluminum Matrix Hybrid Composites Reinforced with Nanoparticles of Al2O3 and TiO2

Abstract

In the present work, the dry sliding wear behavior of Al-12wt%Si matrix composites reinforced with hybrid addition of 2, 4 and 6wt.% (Al2O3 + TiO2) nano particles were investigated. All nanocomposites samples were fabricated by powder metallurgy and mechanical milling of micro powders of the base alloy (Al-12wt.%Si) and nanopowders of Al2O3 and TiO2, followed by cold pressing at 100 bar and sintering at 520 C for 90 min. Archimedes technique was used to measure the density of sintered samples and porosity calculated as physical tests of sintered samples. Also AFM (Atomic force microscope), SEM (Scanning electron microscope) were used to investigate the morphology of mixed powders and nanocomposites samples. Pin – on disk wear tests were carried out at room temperature under dry sliding conditions with using different normal loads and sliding times. Worn surface micrographs were investigated based on the optical and scanning electron microscopy observations of wear tracks and wear debris morphology. It has been found that the hybrid nanocomposite with 6wt.% (Al2O3 + TiO2) nanoparticles shows the highest hardness than other nanocomposites. Nanocomposites show lower wear rate (better wear resistance) than the base alloy within the same conditions.