Corrosion behavior of electrodeposited Ni-B coatings modified with SiO2 particles

The need for coatings with improved operation is vital to insure safety and high output of industrial plants. Electrodeposition is a valuable surface modification technology that can be used to develop various kinds of coatings. Although, Ni-B coatings have good mechanical properties (hardness and wear) but are suffering from inferior corrosion resistance. The development of Ni-B composite coatings by incorporating insoluble hard particles such as metal oxides (Al2O3, TiO2 ) through electrodeposition process has generated a great interest among the research community because of auspicious improvement in properties. The main purpose of this research work was to study the influence of addition of SiO2 particles on corrosion performance of Ni-B coated surfaces which has not been reported so far. Coatings of Ni-B and Ni-B-SiO2 were deposited on steel through electrodeposition process. The microstructural (SEM) analysis confirms the formation of uniform, dense nodular structure in coatings of Ni-B and Ni-B-SiO2 . Surface examination (AFM) discloses that the addition of SiO2 increases surface smoothness. Electrochemical characterization of the synthesized coatings indicates that Ni-B-SiO2 composite coatings demonstrate better anticorrosion properties when compared to Ni-B. Enhanced corrosion performance may be ascribed to reduction in the active surface area and grain size refinement which reduces the porosity by the addition of inactive SiO2 particles.Scopu

Synthesis and Performance Evaluation of Pulse Electrodeposited Ni-AlN Nanocomposite Coatings

This research work presents the microscopic analysis of pulse electrodeposited Ni-AlN nanocomposite coatings using SEM and AFM techniques and their performance evaluation (mechanical and electrochemical) by employing nanoindentation and electrochemical methods. The Ni-AlN nanocomposite coatings were developed by pulse electrodeposition. The nickel matrix was reinforced with various amounts of AlN nanoparticles (3, 6, and 9 g/L) to develop Ni-AlN nanocomposite coatings. The effect of reinforcement concentration on structure, surface morphology, and mechanical and anticorrosion properties was studied. SEM and AFM analyses indicate that Ni-AlN nanocomposite coatings have dense, homogenous, and well-defined pyramid structure containing uniformly distributed AlN particles. A decent improvement in the corrosion protection performance is also observed by the addition of AlN particles to the nickel matrix. Corrosion current was reduced from 2.15 to 1.29 μA cm−2 by increasing the AlN particles concentration from 3 to 9 g/L. It has been observed that the properties of Ni-AlN nanocomposite coating are sensitive to the concentration of AlN nanoparticles used as reinforcement

Enhancement of mechanical and corrosion resistance properties of electrodeposited Ni–P–TiC composite coatings

In the present study, the effect of concentration of titanium carbide (TiC) particles on the structural, mechanical, and electrochemical properties of Ni–P composite coatings was investigated. Various amounts of TiC particles (0, 0.5, 1.0, 1.5, and 2.0 g L−1) were co-electrodeposited in the Ni–P matrix under optimized conditions and then characterized by employing various techniques. The structural analysis of prepared coatings indicates uniform, compact, and nodular structured coatings without any noticeable defects. Vickers microhardness and nanoindentation results demonstrate the increase in the hardness with an increasing amount of TiC particles attaining its terminal value (593HV100) at the concentration of 1.5 g L−1. Further increase in the concentration of TiC particles results in a decrease in hardness, which can be ascribed to their accumulation in the Ni–P matrix. The electrochemical results indicate the improvement in corrosion protection efficiency of coatings with an increasing amount of TiC particles reaching to ~ 92% at 2.0 g L−1, which can be ascribed to a reduction in the active area of the Ni–P matrix by the presence of inactive ceramic particles. The favorable structural, mechanical, and corrosion protection characteristics of Ni–P–TiC composite coatings suggest their potential applications in many industrial applications

Enhanced electrochemical and mechanical performance of BN reinforced Ni-P based nanocomposite coatings

Adequate corrosion protection and improved mechanical properties are necessary requirements to overcome operational costs in the industries. Ni-P based coatings are known to possess better superior corrosion resistance than its counterparts. Boron Nitride nanoparticles (BNNPs) are well known refractory material with higher hardness and chemically inert nature suitable for reinforcement. In the current investigation, the effect of incorporation and increasing concentration of BNNPs in Ni-P matrix in thoroughly investigated in terms of mechanical and electrochemical performances. Successful incorporation of BNNPs within the Ni-P matrix was achieved by employing tailored Watts bath and optimized deposition parameters. The addition and increment of BNNPs reveal a significant impact on the characteristics of pure Ni-P coatings. Improvement in the structural, morphological, mechanical and corrosion behavior of BNNPs reinforced nanocomposite coatings can be ascribed to uniform incorporation of BNNPs in the deposit leading to the dispersion hardening effect that enhances strength to the coating improving surface hardness up to 58 % in comparison to pure Ni-P coating. Moreover, reduction in the active area caused by inert BNNPs leads to the improvement in corrosion resistance properties with protection efficiency (PE%) reaching up to 95 % for Ni-P-1.5 g/L BN nanocomposite coating in comparison to the bare mild steel substrate. BNNPs reinforced Ni-P based nanocomposite coatings provide a possible choice for their application in many industries like in the aerospace, automotive, marine, oil and gas industry.The present work is supported by Qatar University Grant-IRCC-2020-006 and IRCC-2022-491. The opinions expressed in this article are solely the responsibility of the authors. The authors acknowledge the services of Central Laboratory Unit (CLU), Qatar University for Microstructural analysis (FE-SEM/EDS). XPS facility of Gas Processing Center (GPC), Qatar University, was utilized to study compositional analysis. Open Access funding is provided by the Qatar National Library

Novel Ni based duplex coatings for anticorrosion applications

Ni-B/Ni-P-CeO2 duplex coatings containing inner Ni-B layer were synthesized on mild steel substrate through the electrodeposition process. The structural, surface and electrochemical properties of the duplex coatings in their as synthesized condition were compared with Ni-P, Ni-B and binary Ni-B/Ni-P duplex coatings to demonstrate the improved performance of Ni-B/Ni-P-CeO2 duplex coatings. The structural analysis (XRD) indicates that the developed coatings exhibit amorphous behavior. The SEM and AFM studies indicate that Ni-B/Ni-P-CeO2 duplex coatings have less surface defects and more defined nodular structure compared to Ni-P, Ni-B and NiB/Ni-P duplex coatings. However, these coatings show an increase in surface roughness which may be attributed to the incorporation of CeO2 ceramic particles used as reinforcement. The Ni-B/Ni-P-CeO2 duplex coatings present superior anticorrosion properties compared to Ni-B and duplex Ni-B/Ni-P coatings. Owing to tempting properties, Ni-B/Ni-P-CeO2 duplex coatings may be considered as potential candidate for oil and gas industry.This research work was supported by the Director Center for Advanced Materials (CAM), Qatar University, Doha, Qatar.Scopu