The Effect of Milling Time and Sintering Temperature on the Microstructure and Mechanical Properties of Al/20% SiC Composite Prepared by Powder Metallurgy

Metal matrix composites (MMCs) are considered for their mechanical properties and wear resistance. In this study, the effect of milling time and sintering temperature on the microstructure and mechanical properties of Al/SiC composites was studied. Firstly, the powders with volume fraction of Al/20% SiC were mixed in a planetary ball mill under argon atmosphere for milling time of 0.5, 1, 2, 4 and 8 h. Then, the mixed powders were pressed by a cold pressure of 500 MPa into pellets and rods. With regard to the microstructure properties of the samples, the optimized milling time was determined. Then, the pressed samples were capsulated and sintered for 1 h at 400, 450, 500, 550 and 600 0C. Morphology, mechanical and tribological properties of the prepared composites was evaluated by scanning electron microscope (SEM), hardness and wear test. The result showed that the optimized milling time and sintering temperature are 8 h and 600 0C, respectively. Also, density, hardness and wear resistance increase with increasing sintering temperature.