| Ni-TiN nanocomposite coatings with wear resistance,corrosion resistance and oxidation resistance at high temperature,good performance has been gradually used in various industrial fields.However,the conventional preparation method of Ni-TiN nanocomposite coatings deposition rate and the grain is coarse,seriously affect the comprehensive performance of nano coatings.Therefore,in this paper,the ultrasonic assisted spray electrodeposition is used to prepare the Ni-TiN nanocomposite coatings with higher deposition rate block and better performance.This paper mainly studies the plating nickel sulfate concentration,liquid jet velocity,current density,bath temperature,pH value and deposition behavior of ultrasonic power and other parameters of the Ni-TiN nanocomposite coatings,cathodic polarization behavior and the effects of structure and performance,and to determine the optimum process parameters of preparing Ni-TiN nanocomposite coatings.The results show that when the concentration of nickel sulfate is 320 g/l,the injection speed is 4 m/s,the bath temperature is 50,the current density is 10 A/dm2,the pH value is 4,and the ultrasonic power is 150 W,the deposition rate of the coating is higher.By observing the surface morphology of the Ni-TiN nanocomposite coatings prepared under the condition of ultrasonic power 100 W and 150 W,it is found that the surface of Ni-TiN nanocomposite coatings prepared under 150 W condition is smooth and small.The XRD analysis shows that the?1 1 1?crystal surface is slightly enhanced under 150 W conditions,and the existence of Ni and TiN phases in the coating is also proved.Compared with the ultrasonic power of 100 W,when the ultrasonic power is 150 W,the wear rate of the Ni-TiN nanocomposite coating increases with the increase of wear time,indicating that the coating prepared by 150 W condition has better wear resistance.After 20 d corrosion test,the Ni-TiN nano coating prepared at the ultrasonic power of 150 W power is more smooth and compact.From the view of local enlargement,the TiN particles are more distributed with more uniform distribution and no obvious cracks.With the increase of corrosion period,the Ni-TiN nanocomposite coatings without ultrasonic is the fastest growth rate of corrosion and weight loss,while the Ni-TiN nanocomposite coatings prepared at ultrasonic power of 150 W has the smallest corrosion and weight loss.Through Tafel curve,compared with the ultrasonic power 100 W,ultrasonic power of 150 W under the condition of Ni-TiN nanocoatings prepared by the corrosion potential shifted positively by 70 mV,the corrosion current density is 4.405 x 10-5A/cm2,through the comparison of electrochemical impedance spectroscopy,the charge transfer resistance Rct up to 5528?·cm2.The former is much higher than that in 150 W,under the condition of Ni-TiN prepared by nano coating prepared better corrosion resistant performance.By establishing the AR model to predict the change trend of microhardness of Ni-TiN nanocomposite coatings,it is found that the predicted value is not very different from the experimental value,and the prediction accuracy is 98.17%,which proves the reliability of the AR model. |
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