Process Simulation and Abrasion Behavior of Jet Electrodeposited Ni–TiN Nanocoatings

In this work, we study jet-electrodeposited Ni–TiN composite nanocoatings (CNCs) for improving abrasion resistance as a function of various nozzle diameters. In addition, COMSOL software is utilized to simulate the process of jet electrodeposition, particularly the influence of spraying speed and pressure of the electrolyte on the abrasion resistance of coatings. Optimization of the nozzle diameter to obtain uniform and high-performance coatings showed that a Φ7 mm nozzle diameter generated the optimum spraying speed and spraying pressure, which results in good micro-hardness and abrasion resistance of the Ni–TiN CNCs. Under these conditions, the 45 steel substrates are coated with a compact layer of uniform and nano-sized TiN particles, which are responsible for the high abrasion resistance of our Ni–TiN CNCs. Our study may motivate researchers to study jet electrodeposition in order to obtain abrasion-resistant coatings.

Preparation of Graphene Oxide-loaded Nickel with Excellent Antibacterial Property by Magnetic Field-Assisted Scanning Jet Electrodeposition

Graphene oxide (GO) is recognized as a promising antibacterial material that is expected to be used to prepare a new generation of high-efficiency antibacterial coatings. The propensity of GO to agglomeration makes it difficult to apply it effectively. A new method of preparing GO-loaded nickel (GNC) with excellent antibacterial property is proposed in this paper. In this work, GNC was prepared on a titanium sheet by magnetic field-assisted scanning jet electrodeposition. The massive introduction of GO on the coating was proven by energy disperse spectroscopy and Raman spectroscopy. The antibacterial performance of GNC was proven by agar plate assessment and cell living/dead staining. The detection of intracellular reactive oxygen species (ROS) and the concentration of nickel ions, indicate that the antibacterial property of GNC are not entirely derived from the nickel ions released by the coating and the intracellular ROS induced by nickel ions, but rather are due to the synergistic effect of nickel ions and GO.

High-performance nickel coating on SLM 316L stainless steel processed by jet electrochemical machining and jet electrodeposition

Selective laser melting (SLM) is an important method in additive manufacturing. SLM has obvious advantages for the fabrication of metal parts with complex structure that cannot be processed directly and are manufactured in relatively low amounts. However, the surfaces of the SLM-formed parts contain more adhesive particles and pores than those manufactured by traditional methods, leading to the poor corrosion resistance of the parts and preventing the widespread use of SLM. To solve these problems, jet electrochemical machining and jet electrodeposition combined processing techniques were investigated for the treatment of the substrate surface in this work. Jet electrochemical machining was used to remove the surface defects of the SLM-formed parts, and the results were compared with the traditional sandblasting and sandpaper grinding surface treatment methods. Then, the nickel coating was deposited on the surface of the SLM-formed parts using jet electrodeposition to protect the surface and extend the service life of the parts. The mechanisms of the different processing techniques were analyzed, and properties such as the substrate morphology, coating morphology, corrosion resistance of the coating, and adhesion of the coating were compared. The results show that holes, adhesive particles and other defects are still present on the substrate surface after sandpaper grinding and sandblasting and affect the quality of the nickel coating. After electrochemical machining, the SLM surface defects were almost completely removed, forming a uniform microporous structure that interlocked with the nickel coating. The coating was smooth and dense and showed the best corrosion resistance and binding force. In 3.5 wt% NaCl solution, the corrosion potential reached −0.196 V, and the maximum binding force reached 35 N.

Simulation and Experimental Research on Nickel-based Coating Preparedby Jet Electrodeposition at Different Scanning Speeds

In order to study the processing mechanism of jet electrodeposition and explore the influence of different scanning speed on the wear and corrosion resistance of nickel-based coating prepared by jet electrodeposition. The reciprocating scanning motion of the nozzle was used to prepare the nickel-based coating in a specific area. Combined with COMSOL software, the coupling effect of multiple physical fields in the process of jet electrodeposition at different scanning speeds was numerically calculated. Scanning electron microscope, microhardness tester, material surface comprehensive performance tester and electrochemical workstation were used to analyze the surface morphology, section thickness, microhardness, abrasion resistance and corrosion resistance of the nickel-based coating prepared by jet electrodeposition at different scanning speeds. Results show that with the increase of scanning speed, coating grain size decreases, and the coating thickness increases after the first decreases, and microhardness increase after decreases first, abrasion resistance and corrosion resistance were lower after increase first, When the scanning speed reaches 600mm/min, the jet electrodeposited nickel-based coating has the best performance, the maximum thickness reaches 24.83μm, the microhardness reaches 616.86HV, and the wear scar area is 2766.75μm2. In addition, the self-corrosion potential is -0.33V, the self-corrosion current density is 5.16E-7A·cm2, and the equivalent impedance is 4660Ω. The experimental results are consistent with the simulation results, which verifies the accuracy of the simulation model and provides theoretical guidance for further experiments related to jet electrodeposition.

Fabrication of Superhydrophobic Ni-Co-BN Nanocomposite Coatings by Two-Step Jet Electrodeposition

The stability of hydrophobic surface has an important influence on the application of superhydrophobic function. The destruction of hydrophobic micro-nano structures on the material surface is the main factor leading to the loss of superhydrophobic property. In order to improve the corrosion resistance of superhydrophobic surface, Ni-Co-BN nanocomposite coatings with superhydrophobic property were prepared on 45 steel by two-step jet electrodeposition. The surface morphology, water contact angle, and corrosion resistance of the samples were measured and characterized by scanning electron microscope, surface contact angle measuring instrument, and electrochemical workstation. The results of electrochemical analysis show that the superhydrophobic property improved the corrosion resistance of Ni-Co-BN nanocomposite coating. The enhanced corrosion resistance is of great significance to the integrity of the microstructure and the durability of the superhydrophobic function.