Electroless Ni-P/nano-CeO_2 composite coating was prepared in acidic condition,and its microstructure and corrosive property were compared with its CeO_2-free counterpart.Scanning electronic microscopy (SEM) and X-ray diffraction (XRD) spectrometer were used to examine surface morphology and structure of the as-plated coating.Differential scanning calorimeter (DSC) and transmission electronic microscopy (TEM) were used to study the coating's phase change at high temperature.The coating's corrosive behavior in 3%NaCl+5%H_2SO_4 solution was also investigated.The results showed that Ni-P coating had partial amorphous structure mixed with nano-crystals,while the Ni-P/CeO_2 coating had perfect amorphous structure.In high-temperature condition,Ni_3P precipitation and Ni crystallization took place in both coatings but at different temperatures,while the Ni-P/CeO_2 coating had sintered phase of NiCe_2O_4 spinels.The anti-corrosion property was better in the CeO_2-containing coating,and this was due to its less liability to undergo local-cell corrosion than its CeO_2-free counterpart.Ni-P/CeO_2 coating's pure amorphous structure was the result of Ni's hindered crystal-typed deposition and P's promoted deposition.
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