Structural and mechanical characterization of Al-based composite reinforced with heat treated Al2O3 particles

Highlights: • Al2O3 crystals added to the metal matrix of the liquid aluminum. • Heat treatment applied on the Al2O3 powders, changed the morphology of the powders. • Heat treatment of particles results in finer grins and subsequently more wettability. • Addition of heat treated alumina to A356 could increase the mechanical properties. - Abstract: In this study, the addition of 1.00 wt.% Al2O3 crystals to the metal matrix of the liquid aluminum was studied. In order to investigate the influence of heat treatment on activation of Al2O3 powders and mechanical properties of Al–Al2O3 composites, the Al2O3 particles were heated at 1000 °C. X-ray Diffraction (XRD) analysis used to characterize the crystal lattice of Al2O3 and its variation during heat treatment. The size and morphology of the Al2O3 grains was evaluated by Scanning Electron Microscopy (SEM). The results showed a considerable change in morphology of Al2O3 grains during the heat treatment. Mechanical evaluation such as hardness, compression and wear tests showed enhancement in the properties of Al–1.00 wt.% heat treated Al2O3 vs. Al–1.00 wt.% Al2O3 composite