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This study presents a novel approach to enhancing the performance of Ni-W-SiC coatings through magnetic field-assisted electrodeposition, with a specific focus on the influence of magnetic field orientation. The coatings were evaluated for their structure, surface topology, roughness, corrosion resistance, and wear resistance. The results indicated that the perpendicular magnetic orientation of the coating, obtained at a magnetic field value equal to 0.3 T (S1), showed the largest content of SiC, with a minimal grain size of Ni-W, measuring 84.7 nm with smooth, fine, and dense surface architecture. The S1 coating's surface roughness, as revealed by AFM images, was 24.46 nm, significantly less than that of the coatings produced with 0 T (S0) and 0.3 T (S2) magnetic inductions. XRD results revealed that the Ni-W grains' predominant growth direction shifted from the planar direction of (200) to the (111) direction, due to the application of a magnetic field oriented perpendicularly. In addition, the S1 coating had an outstanding corrosion resistance. Furthermore, S1, among all coatings, had the highest value of hardness, along with the lowest coefficient of friction and higher wear resistance. This work sets the stage for future advancements in surface engineering, demonstrating the potential of magnetic field orientation as a tool for material enhancement. [ABSTRACT FROM AUTHOR]

This work describes the process of synthesizing magnesia (MgO) nanomaterials through ultrasonic electrodeposition, followed by an examination of their ability and mechanism to remove Pb(II) from industrial soil at 100, 150, and 200 W ultrasonic powers. Nanomaterials were examined for their surface shape and phase composition using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffractometry (XRD). The capability of magnesia nanomaterials to adsorb Pb(II) improved greatly when operated at 150 W, attaining a maximal 68.94 mg/g value. Adsorption of Pb(II) onto magnesia nanomaterial surfaces was examined by utilizing the pseudo-second-order kinetic and Langmuir models. The nanomaterials exhibited significant features of both chemical and monolayer adsorptions for Pb(II) as a result of the intense chemical interactions between the atoms of the magnesia nanomaterials' surface and Pb(II), as shown by Fourier transform infrared (FTIR) analysis. At 30 °C, the magnesia nanomaterial exhibited the highest adsorption capacity for Pb(II), suggesting that temperature played a significant role in this capacity. Furthermore, the Langmuir model produced a correlation coefficient greater than 0.99, indicating an excellent fit for the adsorption behavior of magnesia towards Pb(II). The findings suggest that ultrasonic power significantly impacts the adsorption characteristics of magnesia nanoparticles synthesized via ultrasonic electrodeposition. Specifically, ultrasonic power of 150 W yields the most efficient adsorption characteristics. Moreover, the 150 W-fabricated magnesia materials demonstrated exceptional pH compatibility. [ABSTRACT FROM AUTHOR]

The high concentration of fluoride ions in industrial wastewater poses a threat to both human safety and the ecological environment. In this paper, three types of magnetic NiO nanomaterial (MNN) with nickel–iron ratios of 3:1, 2:1, and 1:2 were successfully prepared using the electrodeposition technique to eliminate fluoride ions (F−) from industrial wastewater. The surface morphology, phase composition, and chemical structure of the nanomaterials were analyzed using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The results demonstrate the MNN material's exceptional adsorption capabilities for fluoride ions (F−) at a nickel–iron ratio of 3:1, with a maximum adsorption capacity of up to 58.3 mg/g. The adsorption process of fluoride on the MNN material was further examined using Langmuir and pseudo-second-order kinetic models, revealing predominantly monolayer adsorption and chemisorption characteristics. When the amount of FeSO4•9H2O added is minimal, only the distinctive peaks of NiO are visible in the product's spectrum. However, as the Ni/Fe ratio decreases, characteristic peaks of Fe3O4 crystals begin to appear and gradually intensify, indicating an increase in Fe3O4 content within the MNN material. Additionally, the pH level significantly affects the adsorption of fluoride ions (F−) onto the MNN material, with the highest adsorption capacity observed at pH 7. [ABSTRACT FROM AUTHOR]

This study focuses on depositing Ni/W-Al2O3 nanocomposites onto a low-carbon substrate using the pulse electrodeposition technique. The effects of pulse current density on microstructural characteristics, microhardness, phase structure, and wear/corrosion properties of Ni/W-Al2O3 nanocomposites were investigated. Among the investigated nanocomposites, Ni/W-Al2O3 deposited at 0.6 A/dm2 current density showed the finest structure with average Ni-W grain and Al2O3 nanoparticle sizes of 66.7 nm and 39.1 nm, respectively. The Ni/W-Al2O3 nanocomposite deposited under the same conditions exhibited a maximum microhardness of ~ 825.7 HV, while also demonstrating the lowest corrosion current density of ~ 0.72 A/cm2. After 60 min of wear testing, wear loss of Ni/W-Al2O3 nanocomposite deposited at 0.6 A/dm2 was recorded as 42.8 mg, indicating its excellent wear resistance. In contrast, Ni/W-Al2O3 nanocomposite deposited at 0.8 A/dm2 displayed the highest wear loss value of 101.5 mg. [ABSTRACT FROM AUTHOR]

The current paper reports successful syntheses of Ni-TiN composite coatings via pulse current (PC) and magnetic PC (MPC) depositions. The microstructural, nanomechanical, wear properties and wear mechanism of the Ni-TiN composite coatings were investigated via scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), X-ray diffraction (XRD), a nanoindenter (NI) and a high frequency reciprocating wear test instrument. The results showed that the Ni-TiN composite coating deposited at magnetic intensity of 0.3 T had numerous homogeneously dispersed TiN particles. The size of the Ni grains and the TiN particles in the coating were of nanometer size, with an average diameter of ∼65 nm and ∼25 nm, respectively. The maximum hardness and Young’s modulus values for the Ni-TiN composite coatings, deposited at magnetic intensity of 0.3 T, were 34.85 GPa and 165.2 GPa, respectively. The wear results showed that the weight loss of the Ni-TiN composite coating was approximately 47.4 mg at a magnetic density of 0.3 T. Furthermore, the coatings deposited at 0.3 T presented low friction coefficients, with an average value of about 0.43.

Ni-AlN thin films were successfully fabricated via direct-current (DC), pulse-current (PC), and ultrasonic-assisted pulse-current (UAPC) deposition. The microstructure, microhardness, and erosion characteristics of the Ni-AlN thin films were determined with the use of scanning probe microscopy (SPM), X-ray diffraction (XRD), Vickers hardness test, electrochemical station, and scanning electron microscopy (SEM). SPM results revealed that the Ni-AlN thin films synthesized by UAPC deposition have a compact and fine morphology with average grain diameters of the Ni and AlN particles of approximately 97.7 and 40.2 nm, respectively. Based on the XRD results, the Ni-AlN thin films consist of Ni and AlN phases. The Ni-AlN thin films prepared by DC, PC, and UAPC deposition at 4.5 A/dm2 current density exhibited an optimum microhardness value of 904, 943, and 987 HV, respectively. Based on the erosion test results, the films prepared by UAPC deposition possesses the best corrosion resistance among the prepared thin films. The corrosion potentials of the DC-, PC-, and UAPC-deposited films were -0.552, -0.473, and -0.446 V vs. SCE, respectively.

A pure Ni coating and a Ni--nano-SiC composite coating were prepared on the surface of low-carbon steel by magnetic field-assisted electrodeposition in a bath containing NiSO4⋅6H2O 285 g/L, NiCl2⋅6H2O 28 g/L, H3BO3 25 g/L, cetyltrimethylammonium bromide 80 mg/L, and nano-SiC particles (35 nm in size averagely) 0 g/L or 7 g/L at pH 4.8, temperature 46 °C, current density 5.5 A/dm², duty cycle 30%, and magnetic field strength 0.2 A/m or 0.4 A/m for 30 min. The microstructure, microhardness, and wear resistance of pure Ni coating and Ni--nano-SiC composite coatings were compared. The effect of magnetic field strength on the properties of coatings was studied. The results showed that the Ni--nano-SiC composite coating obtained at 0.2 A/m was more uniform and compact, and had higher microhardness and wear resistance as compared with the pure Ni coating prepared at the same magnetic field strength. The properties of Ni--nano-SiC composite coating would be further improved if the magnetic field strength was increased to 0.4 A/m during the electrodeposition. [ABSTRACT FROM AUTHOR]

In this work, Ni–Al2O3 thin nanocoatings (TNCs) containing γ-Al2O3 nanoparticles were fabricated by ultrasonic-agitated electrodeposition (UAE). The influence of ultrasonic power on the microstructure, surface topography, phase structure, microhardness, and wear and corrosion performance was also discussed in detail. These results demonstrated that ultrasonic power had a considerable influence on the surface microstructures of the Ni–Al2O3 TNCs. At an ultrasonic power of 300 W, the microstructure of the NA-3 TNC changed significantly; the surface was compact, fine, and smooth in the micro-area and contained the highest level of Al2O3 (9.9 wt%). Diffraction peaks of the Ni grains in all Ni–Al2O3 TNCs appeared at 44.65°, 52.20°, 76.85°, and 92.55° assigned to the (1 1 1), (2 0 0), (2 2 0), and (3 1 1) planes, respectively, and corresponded to a face-centered cubic structure. The microhardness values of the Ni–Al2O3 TNCs initially increased before decreasing slightly as the ultrasonic power increased from 100 to 400 W. The NA-3 TNC had the highest microhardness (~ 916.2 Hv) among the Ni-Al2O3 TNCs tested. Furthermore, the NA-3 TNC processed the lowest corrosion current density (0.034 µA/mm2) and the highest maximum corrosion resistance. The average wear rate for the NA-3 TNC was only 26.1 mg/min. [ABSTRACT FROM AUTHOR]