The Ni-TiN nanocomposite film was successfully electrodeposited on brass copper substrates.The microstructures of the Ni-TiN nanocomposite film were investigated using scanning electron microscopy(SEM) and transmiss...The Ni-TiN nanocomposite film was successfully electrodeposited on brass copper substrates.The microstructures of the Ni-TiN nanocomposite film were investigated using scanning electron microscopy(SEM) and transmission electron microscopy(TEM).Its average grain size was analyzed through X-ray diffraction(XRD),and its anti-corrosion property was studied through potentiodynamic scanning curves and electrochemical impedance spectroscopy(EIS).The results show that the morphology of Ni-TiN composite film is sensitively dependent on the electroplating current density,TiN nanoparticle concentration,solution stirring speed,bath temperature and pH value of solution.The average grain size of the optimized nanocomposite film is about 50 nm.Meanwhile,the Ni-TiN nanocomposite films are much more resistant to corrosion than pure Ni coatings.展开更多
The corrosion process of AZ91D magnesium alloy in neutral 1%(mass fraction) sodium chloride aqueous solution was investigated by electrochemical noise(EN),SEM and EDX. Fractal theory was primarily used to depict the c...The corrosion process of AZ91D magnesium alloy in neutral 1%(mass fraction) sodium chloride aqueous solution was investigated by electrochemical noise(EN),SEM and EDX. Fractal theory was primarily used to depict the corrosion process of the alloy. The fast wavelet transform(FWT),as well as the fast Fourier transform(FFT),was employed to analyze the EN data. The results show that the overall corrosion process can be described by three stages. The first stage corresponds to the pit nucleation and growth; the second stage involves the growth of a passive oxide layer; and the third stage involves reactivation. With increasing immersion time,fractal dimension increases fast initially,fluctuates in the medium and increases again at last. Pitting corrosion and fractal dimension increase due to the initiation and formation of pits in the initial and the end of immersion,while depresses due to the passivation in the medium period. The results of SEM and EDX support the above conclusions.展开更多
基金Projects(50771092,21073162) supported by the National Natural Science Foundation of ChinaProject(2005DKA10400-Z15) supported by the Ministry of Science and Technology of China
文摘The Ni-TiN nanocomposite film was successfully electrodeposited on brass copper substrates.The microstructures of the Ni-TiN nanocomposite film were investigated using scanning electron microscopy(SEM) and transmission electron microscopy(TEM).Its average grain size was analyzed through X-ray diffraction(XRD),and its anti-corrosion property was studied through potentiodynamic scanning curves and electrochemical impedance spectroscopy(EIS).The results show that the morphology of Ni-TiN composite film is sensitively dependent on the electroplating current density,TiN nanoparticle concentration,solution stirring speed,bath temperature and pH value of solution.The average grain size of the optimized nanocomposite film is about 50 nm.Meanwhile,the Ni-TiN nanocomposite films are much more resistant to corrosion than pure Ni coatings.
基金Projects(50471043, 50771092) supported by the National Natural Science Foundation of ChinaProject(2005DKA10400-Z15) supported by the National R&D Infrastructure and Facility Development Program of ChinaProject supported by Key Laboratory for Ultra-light Materials and Surface-treatment Technology of Education Ministry of China
文摘The corrosion process of AZ91D magnesium alloy in neutral 1%(mass fraction) sodium chloride aqueous solution was investigated by electrochemical noise(EN),SEM and EDX. Fractal theory was primarily used to depict the corrosion process of the alloy. The fast wavelet transform(FWT),as well as the fast Fourier transform(FFT),was employed to analyze the EN data. The results show that the overall corrosion process can be described by three stages. The first stage corresponds to the pit nucleation and growth; the second stage involves the growth of a passive oxide layer; and the third stage involves reactivation. With increasing immersion time,fractal dimension increases fast initially,fluctuates in the medium and increases again at last. Pitting corrosion and fractal dimension increase due to the initiation and formation of pits in the initial and the end of immersion,while depresses due to the passivation in the medium period. The results of SEM and EDX support the above conclusions.