Incorporation of Silicon Carbide and Alumina Particles into the Melt of A356 via Electroless Metallic Coating Followed by Stir Casting

It is known that Cu and Ni coating layers provide different surface energy functionalities when coated onto ceramic particles with a range of particle sizes. This is known to be due to some extent to the kinetic aspects in the bath during the electroless deposition process. In this study, A356-based composites reinforced by 1.5 wt. % large Al2O3 and 1.5 wt. % fine SiC particles were fabricated by a two-step process, semi-solid stir casting followed by rolling. For wettability improvement, the Ni and Cu layers were coated on both the ceramic particles, separately. The results indicated that the best mechanical properties were obtained for a composite, which contained 1.5 % wt. SiC and 1.5 % wt. Al2O3, in which SiC particles were coated by the copper and alumina particles were coated by the nickel.