The processing of Al-25%Si alloy reinforced by 0, 5, 10 and 15wt. % Al2O3 using PM technique by mixing of powder in a double cone mixer, warm compaction of composite powder followed by sintering at temperature of 550ã C for one hour. The mechanical properties, microstructure features, electrical resistivity and wear rate were measured. The results show that the powder of (Al-25%Si) produced by atomization is almost spherical in shape with average particle size of
150µm, apparent density of 0.949g/cm3 and flow rate of 22 s / 50gm. Optical investigation of sintered specimens shows a fairly good distribution of reinforced alumina particles through out the microstructure. Compressive strength increases by adding Al2O3 reinforcement but exhibits a
low ductility. Hardness value increases directly by the increase of reinforcement percent.
Composites containing 15% Al2O3 exhibits a high hardness (152 Hv) and excellent wear resistance.
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