Abstract
SiC composite Ni-P alloys were electrodeposited from normal Watt's type baths in which 20-160g/L SiC powder was suspended. The SiC particles were easily codeposited using baths containing H3PO3. Uniformity of the particle dispersion in the deposit, and the soundness of the interface between SiC and the amorphous Ni-P matrix were examined by scanning and transmission electron microscopes. The thermal stability of the amorphous Ni-P matrix in the composite alloys was studied by differential scanning calorimetry. Vickers hardness tests were also done to study the effects of SiC content and heat treatment. It was found that 1) Composite Ni-P-SiC alloys containing 3.5-7.2wt%SiC were obtained by suspending 20-160g/L SiC in the electrolytic bath; 2) The crystallization temperature of the amorphous matrix decreased with an increase in SiC content; 3) The hardness of the amorphous Ni-P deposites tended to increase slightly with an increase in SiC content. These deposits hardened greatly after being heat treated up to 450°C.
