Effect of SiC particle morphology on Co-P electroless coating characteristics

In this study, two kinds of micrometre sized SiC powders (as received and ball milled) were used as the starting materials to investigate the effect of ceramic surface morphology on the coating characteristics. Determined optimised electroless deposition bath values of pH (9) and bath temperature (70°C) were used. It was found that etching pretreatment was very effective on the coating quality for both types of SiC powders. The experimental results indicated that milling of the powders led to the formation of multimodal sized ceramic powders with sharp edges and rough surfaces, which resulted in a uniform adhesive metallic layer on the powders without any crack formation. Finally, the effect of cobalt coating on the incorporation of ceramic particles into the molten aluminium during fabrication of aluminium matrix composite was studied, and it was revealed that a significant improvement in incorporation could be obtained using cobalt coated ceramic particles.