Effects of reinforcement surface modification on the microstructures and tensile properties of SiCp/Al2014 composites

The effects of reinforcement surface modification on the microstructures and tensile properties of 3 vol% SiCp/Al2014 composites fabricated by semi-solid stir casting were investigated. The distribution of oxidized as well as Ni coated SiC particles in the casting composites was the most homogeneous, followed by the Cu coated SiC particles and then the untreated SiC particles. The reinforcing effect for the tensile properties of the composites reinforced by SiC particles with different surface modifications is as follows: oxidized SiC (1273 K and 3 h)>Ni coated SiC>Cu coated SiC>untreated SiC. Furthermore, the optimal particles oxidation parameters (1373 K and 3 h) were achieved based on the microstructures and tensile properties of the extruded composites. The yield strength and ultimate tensile strength (318 and 529 MPa) of the extruded composites reinforced with optimal oxidized SiC particles are 35.9% and 15% higher than those of the extruded Al2014 matrix alloy (234 and 460 MPa), respectively.