Pulse electro co-deposition of submicron-sized TiC reinforced Ni-W coatings: tribological and corrosion properties

Abstract

Nickel-Tungsten-Titanium carbide (Ni-W-TiC) coatings were produced by pulse electrodeposition from a Ni-W electrolyte containing TiC particles. The effects of TiC concentration in the electrolyte on the morphology, crystallite size, microstrain, mechanical, tribology and electrochemical properties of TiC reinforced Ni-W co-depositions were investigated. The highest hardness of 8.3 GPa and modulus of elasticity of 207 GPa were observed in the case of the coating produced at 15 g/L TiC concentration in the electrolyte. The increase in the H/E and H-3/E-2 ratios led to displaying excellent wear resistance of the Ni-W-TiC co-depositions besides high resistance to plastic deformation. A direct correlation was observed between nanoindentation and wear resistance results of reinforced TiC co-depositions. It has also been shown by electrochemical impedance spectroscopy and potentiodynamic polarization analysis that TiC particles can improve the electrochemical properties of the co-depositions because of their barrier effect.