Title: Corrossion Behavior of Ni-W-P Coating in Hypersaline Brine
Abstract:To improve the corrosion resistance of N80steel, Ni-W-P coating was prepared by electroless deposition.The corrosion properties for Ni-W-P coating were investigated in hypersaline ground brine.Results...To improve the corrosion resistance of N80steel, Ni-W-P coating was prepared by electroless deposition.The corrosion properties for Ni-W-P coating were investigated in hypersaline ground brine.Results of weight loss tests show that the corrosion resistance of the Ni-W-P coating is 10 times of N80steel in hypersaline brine at 90 °C.Electrochemical tests show that the current density of Ni-W-P coated sample reduce from 7.94×10 -2 μA/cm 2 to 4.28×10 -3 μA/cm 2 , and the corrosion potential changes from -0.700 V to -0.398 V compared with N80steel.Scanning electron microscopy (SEM) micrographs and X-ray photoelectron spectroscopy (XPS) were used to evaluate the morphology and composition of the corrosion layer of Ni-W-P coating.The results show that severe intergranular corrosion appear in N80steel, whereas no intergranular corrosion occur in Ni-W-P coating.The chemical composition of the corrosion layer of Ni-W-P coating is NiO,WO 3 , phosphate, and hypophosphite which led to superior corrosion resistance in hypersaline brine.This study confirms that the Ni-W-P coating can be applied for corrosion protection in hypersaline environment.Read More