Electroless Nickel–Phosphorus Plating on SS304 Substrate with Al2O3 and WS2 Powder Suspended in Electrolytic Solution
An attempt has been made in this paper to study the synthesis of Ni–Al2O3–WS2 coating on SS304 substrate with different levels of electroless coating process parameters. The electroless bath constitutes Nickel sulphate, Tri-sodium citrate, Sodium hypophosphite and Ammonium chloride (diluted in 1 litre of deionized water). The substrate with nickel plating showed microhardness value of 221.4 HV that was more than that of the base metal (113 HV). On addition of Al2O3 and WS2 powders in the electroless bath solution, the microhardness value varied between 277.71 HV to 792.79 HV. The coating thickness increased from 10.2625 to 27.9482 μm with the addition of powders in the bath. The energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) analysis results confirmed the transfer of bath elements to the substrate surface.
KeywordsElectroless plating Microhardness Coating thickness Microstructure