Preparation and characterization of the Al-Cu-Mg-Si-Mn composites reinforced by different surface modified SiC p

Abstract In this paper, the 4 vol% SiC p /Al-Cu-Mg-Si-Mn composites were prepared by method of stirring casting. The effects of SiC p surface modifications (oxidization and Ti-coating) and particle sizes (5 μm, 10 μm and 15 μm) on the microstructure and tensile properties of the composites were analyzed. The effects of SiC p sizes on the distribution of SiC p in the pre-oxidized SiC p /Al-Cu-Mg-Si-Mn composites were larger than those in Ti-coated SiC p /Al-Cu-Mg-Si-Mn composites. The Al-Cu-Mg-Si-Mn composites reinforced with Ti-coated SiC p exhibited more uniform SiC p distributions and higher tensile mechanical properties than those reinforced with the pre-oxidized SiC p . When the SiC p size was 15 μm, the Ti-coated SiC p /Al-Cu-Mg-Si-Mn composite showed the best yield strength (σ 0.2 ), ultimate tensile strength (σ UTS ) and fracture strain (e f ) of 410 MPa, 548 MPa and 7.6% with the increase of 10.2%, 2.6% and 5.6% than that of reinforced by pre-oxidized SiC p . The more uniformly dispersed particles and better tensile properties of the Ti-coated SiC p /Al-Cu-Mg-Si-Mn composites could be attributed to the better wetting between Ti-coated SiC p and molten Al.