Electroplating Technology for Amorphous Ni-P/Nano-SiC Composite Coating

Hard and wear-resistant nanoparticles of SiC were introduced in the electroplating bath for amorphous Ni-P coating so as to prepare Ni-P/nanoSiC composite coating.The influences of the technological parameters such as bath temperature,current density,and SiC concentration in the plating bath on the P content and distribution of nano-SiC in the composite coating were investigated.The morphologies of the composite coatings were observed using a scanning electron microscope,while the hardness of the coatings was determined using a nano-microhardness instrument.It was found that the content of nano-SiC in the composite coating increased with increasing electric current and the concentration of SiC in the plating bath.Moreover,the incorporation of nano-SiC contributed to greatly increase the hardness of the Ni-P coating prepared at a bath temperature of 60 ℃,with the maximum hardness of the Ni-PSiC composite coating to be as much as 7.4 GPa,which is much larger than that of the amorphous Ni-P coating.