Microstructural characterization of SiO2/Ni nanocomposites electrodeposited from a sulphate bath modified by PEI

摘要: Abstract SiO2/Ni nanocomposite coatings containing well-dispersed SiO2 nanoparticles were electrodeposited from a sulphate bath with and without the addition of polyethylenimine (PEI) as cationic surfactant. The surface morphology microstructure in cross-sections deposited nanocomposites examined by scanning electron microscopy. More detailed characterization was performed using transmission, scanning-transmission high resolution transmission It determined that 0.05 g/L 0.1 g/L PEI allows incorporation nickel matrix to be increased comparison Based on spatial microanalysis, count rate energy dispersive spectroscopy characteristic X-rays mode, distribution visualized elemental maps. Image analysis microscopy images enabled mean equivalent circle diameters grains determined, together volume fraction nanocomposites. clusters SiO2/Ni + PEI is equal 18.4% 13.3%, respectively. Furthermore, grain size reduced. combination different imaging techniques confirmed not only present surfactant electrolytic bath, but also incorporates into nanocomposite. Nanocomposites presence exhibit higher hardness, good tribological properties improved corrosion resistance. Although increasing concentration up strongly promotes reduction increase fraction, it causes an embedded microstructure, which results deterioration