ABSTRACT In the present investigation, the tensile properties of A356/Al2O3 nanocomposites at both ambient and elevated temperatures were studied. The A356/Al2O3 nanocomposites were fabricated using a combination between the rheocasting and squeeze casting techniques. The A356 matrix alloy was reinforced with Al2O3 nanoparticulates having average sizes of 60 nm and 200 nm with different volume fractions up to 5 vol%. The results revealed that the A356/Al2O3 nanocomposites exhibited better mechanical properties than the A356 monolithic alloy. Such improvement in the mechanical properties was observed at both room and elevated temperatures up to 300°C. Increasing the volume fraction and/or reducing the size of Al2O3 nanoparticulates increase both the tensile and yield strengths of the nanocomposites.
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