PROPERTIES OF THE MULTI LAYER ELECTROLESS NI-P-ZNO/NI-P-SIC COATINGS

The present investigation is focused on corrosion resistance and micro hardness of duplex Ni-P composite coatings. Duel electroless bath containing ZnO and SiC nano particles individually was used to develop multi pass electroless Ni-P-ZnO/Ni-P-SiC duplex film on substrate material mild steel. Microhardness of thin film was measured by using Vicker's tester. Corrosion resistance of duplex coating is measured in solution with 3.5% NaClby conducting potentiodynamic polarization test. Results confirm duplex coating with Ni-P-SiC as outer layer offers maximum microhardness and Ni-P-ZnO outer layer coating is higher corrosion resistive one.