Structural and Electrochemical Properties of Electrodeposited Ni–P nanocomposite Coatings Containing Mixed Ceramic Oxide Particles

Abstract

Mixed oxide ceramic particles were incorporated into Ni-P matrix to synthesize Ni-P-TiO 2 -CeO 2 nanocomposite coatings. In the present study, the effect of concentration of mixed oxide ceramic particles (TiO 2 and CeO 2 ) on structural, surface and electrochemical properties of Ni-P coating is investigated. The coatings were electrodeposited on mild steel substrate and were then characterized using various techniques. The compositional (EDAX) confirms the co-deposition of TiO 2 and CeO 2 ceramic particles into Ni-P matrix. The structural analysis (XRD) indicates that addition of mixed oxide ceramic particles do not have any prominent influence on the structure of Ni-P coatings as parent amorphous structure is preserved even at high concentration of mixed ceramic particles (7.5 g/l). The SEM and AFM analyses indicate that the synthesized coatings are of fine nodular morphology containing uniformly distributed ceramic particles. However, their excessive amount may lead to agglomeration and surface defects. The surface analysis (AFM) also indicates that the surface roughness increases with the increase in amount of TiO 2 and CeO 2 particles. The enhancement in roughness of coatings can be ascribed to the fact the added ceramic particles are hard and remain insoluble in the Ni-P matrix. The potentiodynamic polarization analysis confirms that incorporation of mixed oxide ceramic particles into Ni-P matrix improves its anticorrosion properties. However, their excessive amount may cause decrease in corrosion resistance due to formation of galvanic cells at the defective metal/coating interface.

Perspectives in corrosion-performance of Ni–Cu coatings by adding Y2O3 nanoparticles

“…Generally speaking, the corrosion resistance improvement after incorporation of the nanoparticles can be mainly associated with three major parameters, as follows: (i) anti-corrosive properties of Y 2 O 3 nanoparticles, (ii) diminishing or even elimination of the existing micro-voids and micro-cracks, and (iii) changing the corrosion mechanism from localized to miscellaneous one since the embedded nanoparticles are uniformly dispersed throughout the microstructure [24,27,28,48]. Turning again to the FE-SEM images of the present work, since the embedded reinforcements uniformly distributed throughout the microstructure of the nanocomposite coatings, they can contribute more strongly to the corrosion resistance improvement.…”

Ni-P-TiO2 nanocomposite coatings with uniformly dispersed Ni3Ti intermetallics: effects of TiO2 nanoparticles concentration

“…This study is the first to report the formation of the Ni 3 Ti intermetallics in the case of electrodeposited Ni-P alloy matrix composite coatings. According to the practical results, the obtained patterns for Ni-P based matrix composite coatings usually show a broad peak corresponded to Ni phase coupled with the peak assigned to the embedded reinforcement particles [26,35,39]. However, in some sense, the peaks corresponded to the embedded reinforcements cannot be emerged due to their low amount [33,40].…”

Electrodeposition of Co-P Coatings Reinforced by MoS2 + Y2O3 Hybrid Ceramic Nanoparticles for Corrosion-Resistant Applications: Influences of Operational Parameters

“…For instance, the inclusion of both polymeric and ceramic agents in a metallic coating can simultaneously enhance its tribomechanical and corrosion characteristics. [56] Unlike most existing papers on metallic coatings reinforced via hybrid reinforcements, [57][58][59] the present research strives to determine the optimum concentration of MoS 2 + Y 2 O 3 nanoparticles in the electrolyte before evaluating the influences of applied current density.…”