Microstructural and mechanical properties of Al-Al2O3 composites focus on experimental techniques

In the present study, Al-Al2O3 composites were prepared. Since temperature and time in casting process are two important parameters, in this investigation a method was used to reduce the harmful effects these factors. In addition, in order to study the wettability and distribution of the reinforcement particle, Al2O3 particles were injected into the melt in four different forms, i.e., untreated Al2O3 particles, heat-treated Al2O3 particles, milled particulate Cu-Al2O3 and Al-Al2O3 composite powder. Microstructural features of the matrix and distribution of Al2O3 particles within it, were evaluated by scanning electron microscopy and optical microscopy. In addition, the variations of hardness, impact energy, yield strength and wear resistance were measured. Results revealed that the maximum values of hardness, yield strength and impact energy are observed for Al2O3-Al reinforced sample with values of 78.7 BHN, 142 MPa and 8.2 J, respectively.