Compression and impact strength study of aluminum-alumina granule composite by squeez-casting method

Aluminum-ceramic metal matrix composite is a class of modern engineering materials with interesting physical and mechanical properties. These composites are used widely in many industrial (aerospace, automobile, electronic ,…). In present study, alumina granules preforms with different size (20-100 µm) were made and sintered at 1300°C and 1400°C for 2 h. Then the preforms were preheated at 700°C for 1h. Finally, molten Al was infiltrated into the preforms under load of 3 MPa by squeeze casting method. After composites making their microstructures were studied by SEM and optical microscope.The microstructure results showed that composite with higher sintering temperature has low porosities and well connected granules. Also, compressive strength, impact resistance and hardness of the composites were investigated. The results showed that sintering temperature improved compressive strength and hardness of the composites, but impact strength decreased. The strength and brittleness of the composites is higher for the composites with high sintering temperature