Jet Electrodeposition Research Articles

Effect of the Pulse Duty Cycle on the Microstructure and Properties of a Jet Electrodeposited Nanocrystalline Copper Coating

Nanocrystalline copper coatings were jet electrodeposited using a square-wave pulse current with three duty cycles (30%, 50% and 70%) and a direct current condition. The effect of the duty cycle on the surface morphology, microstructure, grain growth and mechanical performance of the copper coatings was examined. The experimental results revealed that a decrease in the duty cycle significantly improved the coating surface morphology and microstructure. It was shown that a pulse current at a low duty cycle during jet electrodeposition effectively generated a nanocrystalline structure in the coating and improved the mechanical properties. At a low (30%) duty cycle during pulse current electrodeposition, coatings with a fine and smooth surface and dense microstructure were produced with a minimum grain size of 25 nm, microhardness of 2.37 GPa and tensile strength of 712 MPa.

Pulse jet electrodeposition of nanocrystalline copper and its application as an electrical discharge machining electrode

Pulse jet electrodeposition of nanocrystalline copper and its application as an electrical discharge machining electrode

Compressed Air-Film Encircling Jet Electrodeposition with High Deposition Accuracy

To improve the deposition accuracy and surface quality of the deposited micro-features, a novel compressed air-film encircling Jet ECD was proposed. In the proposed Jet ECD, a high-speed compressed air-film is coaxially encircling the impinging electrolytic jet. Numerical model describing the coupled field of electric field and flow field was established, and some auxiliary observations and measurement experiments were conducted to investigate the distribution characteristics of electric field and hydrodynamics characteristics in the concerned regions as well as the change of the electrolyte jet diameter. And the effect of air-film formation parameters and hydrodynamic parameters of the electrolyte jet on the electrodeposition behaviors during forming patterns and high aspect ratio micro-features were studied. Deposition accuracy and surface quality of the microstructures fabricated by the compressed air-film encircling Jet ECD were evaluated. It was demonstrated that, compared with the traditional Jet ECD, the proposed Jet ECD has a higher deposition accuracy and faster deposition rate (up to 1 μm s−1) as well as better surface quality. In addition, the newly developed Jet ECD has an admirable additive manufacturing ability and a 370 ± 3 μm-diameter smooth column with the aspect ratio of about 20 was successfully manufactured.

Corrosion resistance of Ni-P/SiC and Ni-P composite coatings prepared by magnetic field-enhanced jet electrodeposition.

To extend the working life of 45# steel, Ni–P and Ni–P/SiC composite coatings were prepared on its surface by magnetic field-enhanced jet electrodeposition. This study investigated the effect of magnetic field on the corrosion resistance of Ni–P and Ni–P/SiC composite coatings prepared by conventional jet electrodeposition. The surface and cross-sectional morphologies, microstructure, and composition of the composite coatings were determined by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and X-ray diffraction (XRD), respectively. The corrosion resistance was studied using a LEXT4100 laser confocal microscope. The introduction of a stable magnetic field was found to improve the surface morphology of the coatings, increase the growth rate, and reduce the agglomeration of nano-SiC (3 g L−1, 40 nm) particles, thus significantly improving the corrosion resistance of the coatings. The corrosion potential of the Ni–P coating increased from −0.78 V (0 T) to −0.46 V (0.5 T), and the corrosion current density decreased from 9.56 × 10−6 A dm−2 (0 T) to 4.31 × 10−6 A dm−2 (0.5 T). The corrosion potential of the Ni–P/SiC coating increased from −0.59 V (0 T) to −0.28 V (0.5 T), and the corrosion current density decreased from 6.01 × 10−6 A dm−2 (0 T) to 2.90 × 10−6 A dm−2 (0.5 T).

Prediction of electrodeposited copper ions in high speed jet electrodeposition for MEMS fabrication using ANN

High speed jet electrodeposition offers fabrication of Micro Electro-Mechanical System (MEMS) features. In this technique, high precision and accuracy can be acquired using ultrasonic and controlled environment. This research is an attempt to predict the deposition of copper ion on metallic aluminium substrate. For this, a data set has been generated by performing the experiment multiple times at different variable inputs condition. Consequently, Artificial Neural Network (ANN) has been deployed using MATLAB for prediction. ANN is used to train, test and validate the collected experimental data for development of a function which estimate the electrode deposition rate. The variables include the gap between copper electrode and substrate, voltage applied between electrodes and concentration of CuSO4·5H2O However, no prior data is available to compare the performance because no attempt of ANN implementation has been done specifically in High Speed Jet Electro Deposition (HSJED). The coefficient of correlation R for training, testing and validation proved to be satisfied and came out as 0.94162, 0.98755 and 0.98242 respectively. The performance parameter was Mean Square Error (MSE). The prediction model would help the researcher to know the copper deposition rate and save time and efforts required.

Preparation of Co-Ni Alloy Coating with Stable Composition by Jet-Electrodeposition

Cobalt-Nickel (Co-Ni) alloy coatings were prepared by jet electrodeposition on brass substrate under different Co2+/Ni2+ ratio contents (M = 2:1, 1:1, 1:2 and 1:3) and solution flow rates (from 2.0 to 4.5 L/min). The surface morphology, element content, and phase structure of the coating were observed by scanning electron microscope (SEM), energy dispersive spectrometer (EDS), and X-ray diffractometer (XRD). The hardness and wear resistance of the coatings were also measured. The results showed that the Co content in coatings was greater than 70%, no matter at what flow rate and concentration. With an increase of the flow rate, the Co content in the coating increases, and the grain size on the surface of the coating decreases, which leads to increased hardness of the coating. However, the flow rate of the plating solution has little effect on the grain growth orientation, and the phase structure is dominated by the elemental content of the coating. The coatings are in a single phase of hexagonal close-packed (HCP) when the Co content is more than 80%, while the coatings are in dual phases of the HCP and face-centered cubic (FCC) when the Co content is less than 80%. With an increase in the Co content, the grain size decreases, and consequently, the hardness and wear resistance of the alloy increase. A Co-Ni alloy coating with stable composition can be obtained when the ratio of Co2+ to Ni2+ is 2:1.

Cu-TiO2 composites with high incorporated and uniform distributed TiO2 particles prepared by jet electrodeposition

ABSTRACTCu based composites with high mechanical performance have attracted considerable attention due to their extensive applications. A facile jet electrodeposition method was used to prepare Cu-TiO2 composite coatings with TiO2 content as high as 7.25 wt-%. The high content TiO2 particles with an average size of about 120 nm were uniformly distributed in the Cu matrix. This composite coating showed significantly enhanced microhardness of 218.7 Hv and reduced wear rate of 3.7 × 10−2 mg Nm−1, which was 156.1% higher and 75.3% lower than electroformed pure Cu respectively. The enhanced mechanical performance of Cu-TiO2 composites can be attributed to an improved dispersion strengthening effect. Both high TiO2 content and uniform TiO2 distribution play active roles in enhancing dispersion strengthening effect. With appropriate particle size, jet electrodeposition is an effective approach to making composite coatings with high particle content and uniform particle distribution. These composites prepared by jet electrodeposition show significantly enhanced mechanical performance like high hardness and enhanced wear resistance.

Improvement of microstructures and properties of copper-aluminium oxide coating by pulse jet electrodeposition

Cu-Al2O3 nanocomposite coatings were jet electrodeposited using a direct current and pulse current to enhance the quality of the deposition and its mechanical properties. The composite coating prepared with a pulse current exhibited a smooth surface morphology, dense microstructure and good mechanical properties compared with those of the coatings obtained under direct current conditions. The effect of the pulse parameters, including the current density and pulse frequency, on the morphologies, microstructures, grain growth, and properties of the coatings was also examined. The results show that a high pulse frequency and appropriate current density improved the quality of the deposition and its mechanical properties. A dense nanocomposite copper-alumina deposited coating with an average refined grain size of 26 nm was fabricated with a pulse current density of 400 A dm−2 and a pulse frequency of 5000 Hz. The microhardness and tensile strength of the nanocomposite coating attained maximum values of 2.37 GPa and 692 MPa, respectively, when the optimum deposition conditions were used.

Wear resistance of Ni-Co/SiC composite coating by jet electrodeposition in the presence of magnetic field

The Ni-Co/SiC composite coatings were prepared via jet electrodeposition in the presence of magnetic field. The microstructure and texture orientation of the composite coatings were analyzed via field emission scanning electron microscopy, three-dimensional profiling, and X-ray diffraction. The microhardness and wear resistance were characterized by a microhardness tester and a friction–abrasion testing machine. The results indicated that nano-SiC particles improved the surface morphology of the Ni-Co/SiC composite coating. In jet electrodeposition, globular structure aggregation began to form protrusions in the Ni-Co/SiC composite coating due to nanoparticle agglomeration when 6 g/L of nano-SiC was added. The Ni-Co/SiC (6 g/L) composite coating became uniform and densification by jet electrodeposition in magnetic field, with higher microhardness and better wear resistance. The microhardness of the Ni-Co/SiC composite coating increased to 626 ± 14 HV, and the corresponding friction coefficient was as low as 0.317.

Effect of Thiourea on the Nanocrystalline-Copper Coating Prepared by Jet Electrodeposition

Effect of Thiourea on the Nanocrystalline-Copper Coating Prepared by Jet Electrodeposition

Properties of Jet electrodeposition Nickel Coating on TC4 Alloy Prepared by Selective Laser Melting

Properties of Jet electrodeposition Nickel Coating on TC4 Alloy Prepared by Selective Laser Melting

Wear Resistance of Ni-Based Alloy Coatings

In this paper, nickel-based alloy coatings were deposited on the surface of pure copper by jet electrodeposition. The wear resistance of the coatings was studied by a material surface comprehensive performance tester under dry sliding. Hardness testing, friction, and wear testing were performed to characterize the microhardness, surface morphology, and wear resistance of the coatings. The results indicated that adding Fe and W could refine and purify the microstructure. The coatings with additions of 5 wt.% Fe and 7 wt.% W exhibited the highest wear-resistant properties. Moreover, new compound phases NiO, Fe2O3, and WO3 were found on the surface coatings, such that the microhardness was higher than that in the other coatings. Detailed discussions on the influences of Fe and W on the sliding wear are presented.

Study on the properties of superhydrophobic nickel coating prepared by jet electrodeposition in a parallel magnetic field

In a parallel magnetic field, a superhydrophobic nickel coating was prepared by jet electrodeposition on a copper substrate. Magnetic nickel particles were added to the plating solution, and the nickel coatings deposited under the parallel magnetic field had a hierarchical structure. The pristine coating was superhydrophilic, but after 10 days, it spontaneously changed to being superhydrophobic, with a water contact angle of up to 152.2° and a rolling angle of 6°. XPS analysis showed that the reduction in surface free energy was due to the oxidation of nickel and the attached hydrocarbons. Meanwhile, the superhydrophobic coating illustrated excellent corrosion resistance in 3.5 wt% NaCl solution and a low friction coefficient versus the Si3N4 ball.

The Effects of Pulsed Current Parameters on Porosity of Copper Prepared by Jet Electrodeposition

The Effects of Pulsed Current Parameters on Porosity of Copper Prepared by Jet Electrodeposition

Mechanical properties and corrosion resistance of Ni-Co-SiC composite coatings by magnetic field-induced jet electrodeposition

Ni-Co alloys and Ni-Co-SiC composite coatings were manufactured by magnetic field-induced jet electrodeposition. The microstructure and nanoparticles distribution of the coatings were characterized by field emission scanning electron microscopy, energy dispersive X-ray spectrometry, and X-ray diffraction. The surface roughness, adhesion and corrosion resistance of the coatings were measured using a three-dimensional profilometer, a scratch tester, and an electrochemical workstation. The cellular protrusions on the composite coatings decreased with the addition of nano-SiC particles. However, a large number of small spherical structures grew into large cellular protrusions with an extremely high SiC concentration under traditional jet electrodeposition. The composite coatings under magnetic field-induced jet electrodeposition showed a uniform growth and no protrusions, the nano-SiC particles were also uniformly distributed. The Ni-Co-SiC composite coating exhibited a single-phase solid solution structure, and its adhesion increased to 33.2 N, which was 2.65 times that of the Ni-Co alloy coating. The corrosion current density of the composite coating was 4.768 μA cm−2, which was sufficient to protect sintered NdFeB magnets.

Ultrafast Cu2+ recovery from waste water by jet electrodeposition

As a clean treatment technology, electrodeposition has been widely investigated to remove and recover heavy metals from waste water. However, the applied current density is quite low due to relatively low concentration of heavy metal ions in waste water, which results in low processing rate and long processing time. In this paper, a facile jet electrodeposition method was applied for the removal of Cu2+ and recovery of Cu from dilute Cu2+ concentration wastewater (500 mg/L Cu2+). Ultrahigh current density of 12 A/dm2 was applied by impinging the waste water from nozzle anode to cathode surface with an appropriate rate of 3 m/s. More than 97.4% of Cu2+ from waste water was removed with a satisfied current efficiency of 77.2%, the deposited Cu was in bulk state and can be directly recovered. In comparison, current density applied in conventional electrodeposition of such waste water can only reach 0.6 A/dm2 with current efficiency of 76.3%. Considering nearly 20 times increasing of the Cu2+ recovery rate, our jet electrodeposition method makes it possible to remove Cu2+ and recover Cu from low Cu2+ concentration waste water with high rate and high efficiency.

Properties of Jet-Plated Ni Coating on Ti Alloy (Ti6Al4V) with Laser Cleaning Pretreatment

The surface mechanical properties of the Selective Laser Melting (SLM) formed Ti6Al4V samples were improved by adopting a novel laser cleaning pretreatment process combined with a jet electrodeposition process. This paper aimed to investigate the effects of different laser powers on the morphologies and adhesions of the nickel coatings. The advantages of the laser cleaning process are no grinding, no contact, high efficiency and environmental protection. The morphologies, adhesion, wear resistance, and hardness of the coatings were characterized. The results indicate that when the laser energy density reached 20% (4 J/cm2), the contaminations on the substrate and the oxide layer were removed and the crystalline grain of the coating was 15.3 nm. The shallow pits generated by laser burning increased the adhesion of the coatings. In addition, when the laser energy density increased to 6 J/cm2, a yellow oxide layer was produced on the surface of the cleaned titanium alloy. Moreover, the wear resistance of the titanium alloy after the nickel plating was improved. The wear volume was only 0.046 mm3, and the hardness increased to 1967.6 N/mm2.

Effect of jet electrodeposition conditions on microstructure and mechanical properties of Cu–Al2O3 composite coatings

Jet electrodeposition is an advanced manufacturing technology that can produce metallic nano-scaled microstructures with unique performance. Cu–Al2O3 composite coatings were prepared by jet electrodeposition from a plating bath with nano-Al2O3 particles suspended into the bath. Detailed microstructure changes upon the changes of experimental conditions were characterized using X-ray diffraction (XRD) and scanning electron microscope (SEM). The effect of the deposition conditions on the composite coating mechanical properties was investigated. Experimental results indicated that the Al2O3 particle adding into the electrolyte was able to refine the composite coating grains and enhance the deposit inner-structure as well as compactness, which considerably strengthens the composite coating’s mechanical property. It is proved that the current density in the range of 100~500 A/dm2 could offer grain refining effect and the addition of Al2O3 nanoparticles can effectively promote the composite coating mechanical properties.

Enhanced Wear Performance of Cu-Carbon Nanotubes Composite Coatings Prepared by Jet Electrodeposition.

Cu-carbon nanotubes (CNTs) composite coatings with high CNT content and uniformly distributed CNTs were successfully prepared via jet electrodeposition. Pristine CNTs, without any treatment like acid functionalization, were used. Anionic surfactant sodium dodecyl sulfate (SDS) was used to increase the wettability of the CNTs and improve the content of incorporated CNTs. With an appropriate SDS concentration (300 mg/L) in the electrolyte, the incorporated CNT content is as high as 2.84 wt %, much higher than the values reported using conventional electrodeposition (0.42–1.05 wt %). The high-content CNTs were uniformly distributed in the composite coating. The surface morphology of this composite coating (2.84 wt % CNTs) was flat due to the uniform electric field in jet electrodeposition. In the wear test a with load of 1 N and sliding speed of 0.02 m/s, the wear rate of this composite coating was 1.3 × 10−2 mg/Nm, 85.4% lower than that of pure Cu. The enhanced wear performance of Cu-CNTs composite coatings can be attributed to high CNT content and flat surface morphology.

Fabrication of Ni–Co–BN (h) Nanocomposite Coatings with Jet Electrodeposition in Different Pulse Parameters

In order to study the effects of pulse parameters on jet electrodeposition, Ni–Co–BN (h) nanocomposite coatings were prepared on the surface of steel C1045. The samples were analyzed and characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), laser scanning confocal microscopy (LSCM), microhardness tester, and electrochemical workstation. The experimental results showed that the contents of Co and BN (h) nanoparticles in the coatings changed with the variation of pulse parameters. When the pulse frequency was 4 kHz and the duty cycle was 0.7, their contents reached maxima of 27.34 wt % and 3.82 wt %, respectively. The XRD patterns of the coatings showed that the deposits had a face-centered cube (fcc) structure, and there was an obvious preferred orientation in (111) plane. With the increase in pulse parameters, the surface roughness of the coatings first decreased and then increased, with the minimum value obtained being 0.664 µm. The microhardness of the coatings first increased and then decreased with increase in pulse parameters. The maximum value of the microhardness reached 719.2 HV0.05 when the pulse frequency was 4 kHz and the duty cycle was 0.7. In the electrochemical test, the potentiodynamic polarization curves of the coatings after immersion in 3.5 wt % NaCl solution showed the pulse parameters had an obvious effect on the corrosion resistance of the Ni–Co–BN (h) nanocamposite coatings. The corrosion current density and polarization resistance indicated that the coatings had better corrosion resistance when the pulse frequency was 4 kHz and duty cycle was 0.7.