Pulse electrodeposition and corrosion behavior of Ni–W/MWCNT nanocomposite coatings

Abstract

In this study, Ni-W/multiwalled carbon nanotubes (MWCNTs) composite coatings were successfully deposited on the surface of C45 steel sheet by pulse current electrodeposition. Particularly, a uniform dispersion of MWCNTs in the plating electrolyte bath is indispensable. To achieve this main point, MWCNTs were modified by acidification, and coupled with introduction of sodium dodecyl sulfate to the plating bath. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were employed to characterize the morphology and structure of the composite coatings. The corrosion behavior of the composite coatings on steel was investigated by polarization curves and electrochemical impedance spectroscopy (EIS) in 3.5 wt-% NaCl aqueous solutions with pH of 10, 7, 3 and 10 wt-% HCl solutions at various temperatures, which are representative of corrosive environments of relevance to many engineering applications. The result indicates that the incorporation of MWCNTs made Ni-W composite coatings compact and uniform. Consequently, a higher corrosion resistance and thermal stability of Ni-W/MWCNTs deposits were obtained. The optimal concentration of MWCNTs in the bath is 2g L -1 . Fig.2 SEM images of Ni-W/MWCNTs coatings surface containing (a) 0g L -1 , (b) 2g L -1 of MWCNTs and corresponding Ni(c), W(d), C mapping of the composite coatings on C45 steel with (e) 1g L -1 , (f) 2g L -1 MWCNTs contents, and Cross-sectional SEM image (g) and its backscattered SEM image (h) of Ni-W/MWCNTs coatings containing 2g L -1 of MWCNTs Figure 3 reveals the incorporation of MWCNTs into the growing Ni-W matrix schematically. During the early stage of electrodeposition (Figure 3a), MWCNTs are mechanically entrapped into the growing Ni-W matrix. Due to non-metallic MWCNTs, inclusion of them into the Ni-W matrix reduces the surface of cathode and

Effect of Grit Blasting and Polishing Pretreatments on the Microhardness, Adhesion and Corrosion Properties of Electrodeposited Ni-W/SiC Nanocomposite Coatings on 45 Steel Substrate

“…For objects subjected to a wear environment, two important properties of wear resistance and hardness are essential. Figure 14 described in the previous researches [15,[44][45][46]. One possible reason for this result is that the SiC nanoparticles in the Ni-W-SiC coating blocked the dislocation movement and sliding at the grain boundary of the matrix, thereby increasing the micro-hardness of the Ni-W-SiC.…”

The influence of pulse plating parameters on microstructure and properties of Ni-W-Si3N4 nanocomposite coatings

“…Nevertheless, the research found that Ni dissolved easily from the alloy due to galvanic action [38], while Ni-W-Si 3 N 4 coatings were found to be dense and smooth. Therefore, it is obvious that Si 3 N 4 blocked the dissolution of Ni and the diffusion of corrosive media through adsorbing on the anodic sites, leading to formed a more homogenous and compact coating [12]. Moreover, pulse current electrodeposited coating have better corrosion resistance compared to direct current electrodeposits.…”

“…However, with the growth of hardness and wear resistance, Ni-W coating also increases undesired residual tensile stress. It is a potential strategy that incorporation of particles into Ni-W matrix deposit to reduce residual tensile stress and further improve hardness as well [12]. Also, the co-electrodeposition process could be useful in the improvement of other properties of alloy coating, such as oxidation resistances, corrosion resistances and wear resistances [15].…”

“…Co-electrodeposition refers to an electrolytic process that organic or ceramic particles deposit together with reduced metal ions on a substrate forming a composite structure of metal matrix dispersed by the particles [7]. Various types of nanoparticles with different properties, such as oxides (Al 2 O 3 , ZrO 2 , SiO 2 , TiO 2 ), borides (TiB 2, ZrB 2 ), carbides (SiC, WC) and multi-wall carbon nanotubes (MWCNT), have been successfully co-deposited with microcrystalline metals and alloy phases to form nanocomposites with remarkable properties [8][9][10][11][12][13].…”

Investigation of electro-thermal property of Cu-MWCNT-coated 316L stainless steel

“…It can improve the mechanical as well as thermal and electrical properties. Several researchers have successfully developed Cu-MWCNTs [23,24], Co-MWCNT [25], Co-W-MWCNT [26], Ni-W-MWCNTs [27] and graphine-copper [28] nanocomposites coatings using the electrodeposition process. Ramalingam et al [29] developed Cu-MWCNTs nanocomposite coatings by the electrodeposition technique from optimised bath composition and using optimised process conditions.…”