Chemical composition variation of the Ni–W alloy as a function of parameters used in the electrodeposition process

In this work, Ni–W coatings were manufactured by electroplating from a 2 2 central composite factorial design with two central points and two axial points, totaling ten experiments. The design was used to evaluate the influence of electrodeposition parameters (current density and pH) on the chemical composition of the coatings. All samples were characterized in terms of morphology using scanning electron microscopy and corrosion resistance using potentiodynamic polarization and electrochemical impedance spectroscopy techniques. The results indicated that the coatings obtained at low current densities and acidic pH are rich in W (28 to 31 at%), present microcracks, and are less corrosion resistant. The coatings obtained at alkaline pH and high current densities have average W contents (11 to 19 at%), smooth and homogeneous morphology, and are more corrosion resistant. Graphical Abstract