The effect of SiO2 nanoparticles dispersion on physico-chemical properties of modified Ni-W nanocomposite coatings

In this work, we study the effect of pH on morphology, composition and crystallographic orientation during pulse electroplating of Ni-W/SiO2 nanocomposite coating from citrate-ammonia media. SEM and AFM analysis shows that the nanocomposite coatings obtained with well dispersed SiO2 nanoparticles were smoother, more compact and with finer grain size. Furthermore, XPS, GDOES and XRD reveal a good crystalline structure with the detection of new intermetallic phases. The interface electrochemical behavior and stability of the studied coatings into 3% NaCl media were discussed in the consideration of electrical conductivity and microhardness. (C) 2014 Elsevier B.V. All rights reserved.