| Summary: | A Ti5Si3 coating layer was plated on the surface of SiCP by salt-bath plating. The coating layer greatly promoted the wettability of SiC by the molten Al with the final contact angle decreasing from 94° of uncoated one to 4° at 973 K. The 2 vol.% Ti-coated SiCP/2014Al composites were fabricated by stir casting with the addition of 20 vol.% Ti-coated SiCP/2014Al master alloy. Due to the significant improvement of the wetting between the Ti-coated SiC and Al melt, the interfacial energy between Ti-coated SiCP and Al melt is significantly higher than that between α-Al and Ti-coated SiCP. Therefore, Ti-coated SiCP was more easily engulfed into α-Al grains during solidification, leading to a more homogeneous distribution of SiCP and obvious improvement of tensile property for the composites. The yield strength, ultimate tensile strength and fracture strain of the 2 vol.% Ti-coated SiCP/2014Al composites increased from 389 MPa, 525 MPa and 4.8% of the 2 vol.% uncoated SiCp/2014Al composites to 420 MPa, 576 MPa and 6.8%, respectively. The present work offers a new method to improve the dispersal uniformity of SiCP in the composites. Keywords: SiCP/2014Al composites, Ti-coating layer, Wetting, SiCp engulfment, Tensile properties
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