Development of Nano-tetragonal Zirconia-Incorporated Ni–P Coatings for High Corrosion Resistance

Abstract

Pure tetragonal 10-20-nm-size zirconia-based NiP composite coating was developed. The physicochemical and electrochemical characteristics including corrosion resistance of the coating were investigated. The NiP -nano-tetragonal zirconia coating was partially crystalline having face-centered cubic phase. The coating had very high corrosion resistance due to its dense compact morphology and low surface roughness. The NiP -nano-tetragonal zirconia coatings exhibited a cathodic shift of open-circuit potential (OCP) in the range from-0.340 to-0.520 V. A high polarization resistance of the order of 13.2 kX/cm 2 and low corrosion current density of 3.9 lA/cm 2 were achieved due to the effective incorporation of zirconia into the coating.

Electroless Ni–B–MMT nanocomposite on magnesium alloy

“…In this situation, the weak XRD peaks are not distinguishable due to the low signal-to-noise ratio. Similar findings have been reported many times for the electroless coatings containing different nanoparticles [49][50][51].…”

Impact of ZrO2reinforcement on the surface roughness, electrical and magnetic properties of the nano-permalloy

“…Similarly, in the cathodic region, the current increases initially followed by a gradual decrease and finally become nearly constant that might be due to inhibition of the cathodic reaction. The observed improvement in the corrosion resistance of the composite coatings can be visualized in light of factors such as composition, surface morphology, grain structure (grain size, grain boundary network), heterogeneity of the surface and the nature of the embedded ceramic particles [22][23][24]. The corrosion process is believed to be influenced by the surface modifications of the coatings due to the incorporation of the ZrO 2 particles in the alloy matrix.…”

“…As the blocking of corrosion process by these particles seems prevalent in this case due to their high content; the corrosion resistance of the nanocomposite coating was found to be slightly higher than that of the alloy. It is reported [9,23] that corrosion resistance of nickel matrix improves after reinforcement of ZrO 2 particles because the surface area of metal exposed to the corrosive environment is reduced.…”