Optimization of pulsed electro co-deposition for Ni-B-TiN composites and the variation of tribological and corrosion behaviors

Abstract

In this study, novel Ni-B-TiN metal matrix composite (MMC) coatings were successfully deposited using a nickel Watts bath containing TiN nanoparticles by Pulse Electrodeposition (PED) method. The main purpose is to provide the deposition optimization of Ni-B-TiN and its morphology, mechanical, tribological and corrosion properties of composite coatings. The suspension of the TiN particles in the electrolyte has been studied by zeta potential technique. Deposition morphologies on the coating surface and cross sections, worn surfaces were analyzed with scanning electron microscopy (SEM). Phase structures of the deposited layers were analyzed with X-ray diffraction (XRD), nanoindentation hardness tests were performed on the cross-sections of the depositions and reciprocating ball-on disk tests were carried out for tribological measurements. Corrosion properties of the depositions were studied in 3.5 wt% NaCl solution and electrochemical impedance spectroscopy (EIS) was also applied. Microstructures, coating thickness, mechanical properties, tribological and corrosion tests have demonstrated that the-co-depositions of Ni-B-TiN composite coating mechanisms have governed by Gugliemi's absorption model. According to this model and experimental results, it has been demonstrated that the particle content in the electrolyte of 15 g/L is the optimum concentration to obtain best properties.