Experimental Study On Electroless Preparation Of Fine Powder Of Pure Ni Coating ZrO₂

With the rapid development of high-tech and the improvement of people’s livingstandards, more and more higher to the requirement of all kinds of equipments andinstruments, superiority of composite materials begin to unravel. In particular, thestudy of new composite material is even more important. About few reports of thepure Ni coated ZrO2composite powder, The commercial and industrial manufacturingcomposite powder has not yet appeared, given the ZrO2high temperature resistant,corrosion resistant, heat conduction and metal nickel catalyst, conductive, the electricmagnetic, etc. both homogeneous composite powders, metal-ceramic compositepowder has become, metal-ceramic composite powders have both the two features, toexpand its uses and applications, reading and thinking through a large number of data,electroless plating is the best way to uniform coating.In this study, electroless plating method hydrazine as a reducing agent,nocatalytic activity at the surface of ZrO2plated metal coating of pure Ni. Thecombination of theory and practice, researching the best prescription of platingsolution, by SEM, EDS, metallography, laser particle size analyzer detection methodcombined weight increase, discussing the influence of various factors on thecomposite powder.The hydrazine as the reducing agent, EDTA disodium and compound used incombination with sodium tartrate as complexing agent of thermodynamics analysis ofchemical nickel plating, chemical plating of pure Ni coating ZrO2experiment as anexample for the thermodynamic analysis, through the theoretical calculation of△G ofeach reaction, determine the application conditions is feasible, finally the actualverification by experiment, confirmed analysis of thermodynamics is feasibility andreliability.The powers were studied by orthogonal experiment combined with single factor,The optimum parameters of the plating solution and process conditions: NiSO46H2Omass concentration is19g/L, N2H4H2O mass concentration is123.84g/L, pH is13.4,the temperature is93℃, sodium tartrate mass concentration is18.5g/L, disodiumEDTA mass concentration is8g/L. Take the lead chloride mass concentration0.2mg/L~0.6mg/L range, lead chloride mass concentration in this experiment to take0.5mg/L, Maleic acid mass concentration taken at10mg/L~40mg/L range, maleicacid mass concentration in this experiment to take15mg/L.By SEM, EDS, metallography, laser particle size analyzer detection methodcombined weight analysis using electroless plating method, Using hydrazine as reducing agent, it achieved pure Ni coated ZrO2powder and the effect of Ni coatedZrO2powder is better, the basic realization of the overall coating, to the purpose ofmaximizing the power mixing. Experimental prepared composite powder particles ofnickel mass fraction of15.44%. Ni-coated ZrO2powder particle diameter is50.98μmand the coating thickness is6.745μm. The time of plating experiment is25min andexperimental loading amount of ZrO2is5g/L~12.5g/L.