Effects of SiC Mass Fractions on Microstructure and Properties of SiCp/6061 Aluminum Matrix Composite

The SiCp/6061 aluminum matrix composite was prepared by adding SiC particles with semi-solid stirring method, and then the effects of the adding amounts of SiC particles on microstructures, mechanical properties, wear resistance of the composite were studied. The results show that the SiC particles were distributed evenly in the 6061 aluminum matrix. Moreover the dispersibility first increased then decreased with the increase of SiC particle content and the optimal uniformity was achieved with SiC mass fraction of 20%. With the increase of SiC particle content, the tensile strength, hardness and wear resistance of the composite increased while the elongation decreased. When the mass fraction of SiC particles was 25%, the tensile strength, elongation and wear rate of the composite was 282 MPa, 3.9% ,4.563×10-8 mg·mm-1·mm-2 respectively. Comparing to those of the 6061 aluminum alloy, the tensile strength and wear resistance were improved by 64.2% and 670% respectively while the elongation decreased by 38.1%.