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In this study, an amorphous Al-Ti-Ni coating was fabricated on S355 steel using an arc spraying, and its corrosion behavior immersed in 3.5 per cent NaCl solution for 720 h was discussed, which provided an experimental basis for the application of arc sprayed Al-Ti-Ni coating on S355 steel on marine platform.

An amorphous Al-Ti-Ni coating was sprayed on S355 structural steel using an arc spraying. The surface-interface morphologies, chemical element compositions and phases of the obtained Al-Ti-Ni coating were analyzed using a scanning electron microscope, energy dispersive spectrometer and X-ray diffractometer, respectively. The distributions of chemical elements on the coating surface and interface were analyzed using an energy spectrum scanning; the bonding mechanism between the coating and the substrate was also discussed.

Financial support for this research by the Key Research and Development Project of Jiangsu Province (BE2016052).

In this study, an amorphous Al-Ti-Ni coating was fabricated on S355 steel using an arc spraying, its corrosion behavior immersed in 3.5 per cent 25 NaCl solution for 720 h was discussed.

The purpose of this paper is to investigate the effects of laser power on the electrochemical corrosion performance in 3.5% NaCl, 0.1 M H₂SO₄ and 0.1 M NaOH solutions, which provided an experimental basis for the application of Al–Ti–Ni amorphous coating in marine environment.

Amorphous Al–Ti–Ni coatings were fabricated on S355 structural steel by laser thermal spraying (LTS) at different laser powers. The surface and cross-section morphologies, chemical element distribution, phases and crystallization behaviors of obtained coatings were analyzed using a scanning electron microscope, energy-dispersive X-ray spectroscope, X-ray diffraction and differential scanning calorimetry, respectively. The effects of laser power on the electrochemical corrosion performances of Al–Ti–Ni coatings in 3.5% NaCl, 0.1 M H₂SO₄ and 0.1 M NaOH solutions were investigated using an electrochemical workstation.

The crystallization temperature of Al–Ti–Ni coatings fabricated at the laser power of 1,300 and 1,700 W is ∼520°C, whereas that fabricated at the laser power of 1,500 W is ∼310°C. The coatings display excellent corrosion resistance in 3.5% NaCl and 0.1 M NaOH solutions, while a faster dissolution rate in 0.1 M H₂SO₄ solution. The coatings fabricated at the laser power of 1,300 and 1,700 W present the better electrochemical corrosion resistance in 3.5% NaCl and 0.1 M NaOH solutions, whereas that fabricated at the laser power of 1,500 W exhibits the better electrochemical corrosion resistance in 0.1 M H₂SO₄ solution.

In this work, Al-wire-cored Ti–Ni powder was first on S355 steel with the laser power of 1,300, 1,500 and 1,700 W, and the effects of laser power on the electrochemical corrosion performance in 3.5% NaCl, 0.1 M H₂SO₄ and 0.1 M NaOH solutions were investigated using an electrochemical workstation.

The purpose of this paper is to evaluate the salt spray corrosion (SSC) and electrochemical corrosion performances of CrNi, TiAlN/NiCr and CrNi–Al₂O₃–TiO₂ coatings on H13 steel, which improved the corrosion resistance of H13 hot work mold.

CrNi, TiAlN/NiCr and CrNi–Al₂O₃–TiO₂ coatings were fabricated on H13 hot work mold steel using a laser cladding and cathodic arc ion plating. The SSC and electrochemical performances of obtained coatings were investigated using a corrosion test chamber and electrochemical workstation, respectively. The corrosion morphologies, microstructure and phases were analyzed using an electron scanning microscope, optical microscope and X-ray diffraction, respectively, and the mechanisms of corrosion resistance were also discussed.

The CrNi coating is penetrated by corrosion media, producing the oxide of Fe₃O₄ on the coating surface; and the TiAlN coating is corroded to enter into the CrNi coating, forming the oxides of TiO and NiO, the mechanism is pitting corrosion, whereas the CrNi–Al₂O₃–TiO₂ coating is not penetrated, with no oxides, showing the highest SSC resistance among the three kinds of coatings. The corrosion potential of CrNi coating, TiAlN/CrNi and CrNi–Al₂O₃–TiO₂ coatings was –0.444, –0.481 and –0.334 V, respectively, and the corresponding polarization resistances were 3,074, 2,425 and 86,648 cm², respectively. The electrochemical corrosion resistance of CrNi–Al₂O₃–TiO₂ coating is the highest, which is enhanced by the additions of Al₂O₃ and TiO₂.

The CrNi, TiAlN/CrNi and CrNi–Al₂O₃–TiO₂ coatings on H13 hot work mold were firstly evaluated by the SSC and electrochemical performances.

The purpose of this paper is to investigate the effects of load and speed on the corrosive wear performance of Al coating in 3.5% NaCl solution, which provided an experimental reference for the anti-corrosion engineering on offshore platforms.

A layer of Al coating was prepared on S355 steel using an arc spraying. The corrosive wear test was carried out with CFT–1 type surface property tester. The effects of load and speed on the corrosive wear performance of Al coating were investigated and the wear mechanism was also discussed. The electrochemical tests were conducted using a CHI660E type electrochemical workstation, the anti-corrosion mechanism was analyzed.

The average coefficient of frictions (COFs) of Al coating under loads of 1.5, 2.5 and 3.5 N are 0.745, 0.847 and 0.423, the wear mechanism is abrasive wear. The average COFs of Al coating at the speeds of 200, 400 and 600 rpm are 0.745, 0.878 and 0.617, respectively, the wear mechanism at the speeds of 200 and 400 rpm are abrasive wear, while that at the speed of 600 rpm is abrasive wear and fatigue wear. The anti-corrosion mechanism is the isolation of Cl^– corrosion and cathodic protection of sacrificial anode.

This paper mainly studied corrosive wear and electrochemical corrosion performances of Al coating. This study hereby confirms that this manuscript is the original work and has not been published nor has it been submitted simultaneously elsewhere. This paper further confirms that all authors have checked the manuscript and have agreed to the submission.

The purpose of this paper is to improve the salt spray corrosion and electrochemical corrosion performances of H13 hot work mould steel, Cr–Ni coatings with the different Cr and Ni mass ratios are fabricated using a laser cladding (LC), which provides an experimental basis for the surface modification treatment of H13 steel.

Cr–Ni coatings with the different Cr and Ni mass ratios were firstly fabricated on H13 hot work mould steel using a laser cladding (LC). The salt spray corrosion (SSC) and electrochemical corrosion performances of Cr–Ni coatings in 3.5 Wt.% NaCl solution were investigated to analyze the corrosion mechanism, and the effect of mass ratios of Cr and Ni on their corrosion mechanism was discussed.

The laser cladded Cr–Ni coatings with the different Cr and Ni mass ratios are composed of Cr–Ni compounds, which are metallurgically combined with the substrate. The SSC resistance of Cr–Ni coating with the Cr and Ni mass ratios of 24:76 is the highest. The electrochemical corrosion resistance of Cr–Ni coating with the Cr and Ni mass ratio of 24:76 is the best among the three kinds of coatings.

In this study, the corrosion resistance of laser cladded Cr–Ni coatings with the Cr and Ni mass ratios of 17: 83, 20: 80 and 24: 76 was first evaluated using salt spray corrosion (SSC) and electrochemical tests, and the effect of mass ratios of Cr and Ni on their corrosion mechanism was discussed.

The purpose of this paper is to investigate the interfacial conductivity and corrosion resistance of the Ni–P/Ti₄O₇ composite coating that is deposited on a carbon steel substrate as bipolar plates for proton exchange membrane fuel cells.

The Ni–P/Ti₄O₇ coating was prepared by electroless plating. Scanning electron microscopy, white light interference, energy dispersive spectrometry and X-ray diffraction were used, respectively, to study the surface morphology, chemical composition and phase composition of coated samples. Electrochemical impedance spectroscopy, potentiodynamic and potentiostatic polarization were used to test the electrochemical performance and corrosion behavior. The interfacial contact resistance (ICR) was measured via the standard method.

The surface of the Ni–P/Ti₄O₇ coating is complete and dense and without obvious defects. The electrochemical test results show that the Ni–P/Ti₄O₇ coating provides better corrosion resistance than the Ni–P coating and substrate. Compared with the Ni–P coating, the ICR of the Ni–P/Ti₄O₇ coating is lower by about 82.7%. This is because the coating has more conductive contact points. The more exciting thing is that the ICR of the Ni–P/Ti₄O₇ coating only increases to 12.38 mΩ·cm² after 5 h of polarization.

This paper provides a method for achieving surface modification of metal bipolar plates. Introducing Ti₄O₇ particles in the Ni–P layer reduces the contact resistance before and after polarization while ensuring good corrosion resistance.

This paper aims to investigate the effect of Ti₃SiC₂ on the high-temperature tribological behaviors of NiCr coating, which was beneficial to improve the friction-wear performance of hot work mold.

NiCr-Ti₃SiC₂ coatings were prepared on H13 steel substrate by laser cladding. The microstructure, phases and hardness of obtained coatings were analyzed using a super-depth of field microscope, X-ray diffraction and microhardness tester, respectively, and the tribological performance of obtained coatings at 500°C was investigated using a high-temperature tester.

The results show the NiCr-Ti₃SiC₂ coatings are comprised of γ-Ni solid, solution, Ti_xNi_y, TiC and Ti₃SiC₂ phases, and the coating hardness is increased with the increase of Ti₃SiC₂ mass fraction, which is contributed to the fine-grain and dispersion strengthening effect by the addition of Ti₃SiC₂. The NiCr-Ti₃SiC₂ coatings present excellent friction reduction and wear resistance by the synergetic action of Ti₃SiC₂ lubricant and hard phase, and the wear mechanism is predominated by abrasive wear and oxidation wear.

Ti₃SiC₂ phase was used to reinforce the tribological performance of H13 steel at high temperature, and the roles of friction reduction and wear resistance were discussed.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2023-0004/

This study aims to expand the reliability and special functions of lightweight materials for high-end equipment and green manufacturing, so that it is the first such research to carry out nano-composite technology of nickel-coated carbon nanotubes (Ni-CNTs)-based titanium-zirconium chemical conversion on aluminum alloy substrate.

Corrosion behavior of various coatings was investigated using dropping corrosion test, linear polarization and electrochemical impedance spectroscopy. The results showed that the corrosion resistance of the nano-composite conversion coatings was significantly improved to compare with the conventional titanium-zirconium conversion coating. The morphology and microdomain characteristics of the nano-composite conversion coatings were characterized by SEM/eds/EPMA, which indicated that the CNT or Ni-CNTs addition promoting the integrity coverage of coatings in a short time.

Surface morphology of titanium-zirconium (Ti-Zr)/Ni-CNT specimens exhibited smooth, compact and little pores. The nano-composite conversion coatings are mainly composed of Al, O, C and Ti elements and contain a small amount of F and Zr elements, which illuminated that CNT or Ni-CNT addition could co-deposit with aluminum and titanium metal oxides.

The study of corrosion resistance of nano-composite conversion coatings and the micro-zone film-formation characteristics would be provided theoretical support for the development of basic research on surface treatment of aluminum alloys.

The demand for titanium alloys has received massive attention in the aerospace and automotive industry owing to their magnificent electrochemically compatibility and corrosion resistance, high strength at elevated temperatures and high strength-to-weight ratio. Although titanium alloy has impressive mechanical properties, they are challenging to machine or metal form due to its poor heat conductivity, high chemical reactivity, low modulus of elasticity, high friction coefficient and difficult lubricant that limits its application field and increases wear. However, surface treatment coating with the strong metallurgical bond between the titanium alloy matrixes is novel technique to resolve these challenges. This research will illustrate the influence of laser scanning power on the microstructure and tribological behavior of Nickel (NI)-composite claddings fabricated on TC4 titanium alloy to realize the strong metallurgical bond between the titanium alloy and NI-composite coating.

In this research, TiC/TC4 alloy nanocomposites were fabricated based on different laser power and temperatures. TC4 has been selected as a base material instead of TiC for the strong metallurgical bond between the titanium alloy matrixes. Then Ni-composite coating was used as the surface treatment coating on TC4 by laser cladding (LC) technique. The Ni-based alloy coating material powder is good self-fluxing, has high-temperature resistance and is analytically pure with 200 mesh, which can easily overcome the various challenges of titanium alloy. The chemical properties of Ni composite coating include 31.2% Chromium, 8%Titenium and 3.6% Carbon. The prepared surface treatment coating characterization and microstructure behavior are analyzed using optical micrograph, X-ray diffraction, scanning electron microscopes, energy dispersive spectroscopy and electron probe micro analyzer methods.

It is evident that at the beginning of the experiment, if the laser power increased, the quality of the coating increased. An optimal quality of the coating is found when the laser scanning power about 12.55 kJ/cm². Further increased laser power diminished the quality of the coating because the material plasticity had deteriorated. The TiC ceramic particle reinforced phase is dispersed into a two-phase solid solution of β-Ti and γ-Ni. The micro-hardness of the used coating is greater than the base alloy.

This research has practical value in the modern aerospace and automobile industry to increase the application of titanium alloy.

The purpose of this study is to analyze the slurry erosion failure of Ni-20Cr (Ni-Cr₂O₃), Ni-20Al (Ni-Al₂O₃) and Al-20Ti (Al₂O₃-TiO₂) coatings deposited on SS316L by the high-velocity oxy-fuel process.

Slurry erosion experiments were conducted using a pot type erosion tester at different velocities 1.81, 2.71, 3.61 and 4.59 m/s for the time duration of 90-180 minutes. Fly ash and bottom ash were used as erodent media; the concentration of mass flux was taken as 30-60 wt. per cent. Artificial neural network (ANN) method was used to simulate the slurry erosion for thermally sprayed coatings.

Slurry erosion of coatings increases non-linearly with an increase in experimental durations, mass flux and velocity. Slurry erosion of Ni-20Cr and Ni-20Al layers was found to be maximum at 60° impingement angle, whereas 30° for SS316L and 45° for Al-20Ti coating. Slurry erosion performance of SS316L was improved by 2.56-3.19 times by depositing Ni-20Cr and Ni-20Al layers, whereas it improved 1.15-1.75 times by Al-20Ti coating. The slurry erosion SS316L was found almost 1.35 ± 1.28 times greater than that of the Ni-20Al coating, whereas it was to be 1.12 ± 1.36 times greater than Al-20Ti. Ni-20Al-coated SS316L showed a lower value of slurry erosion than Al-20Ti-coated SS316L.

Stainless Steel SS316L is widely used in hydraulic machinery (such as turbines, pumps, valves, fittings, etc.) of hydraulic and thermal power plants, chemical industry and marine industry. Therefore, the deposition of ductile and brittle coatings is a better option for their durable performance.

Erosion wear of Ni-20Cr, Ni-20Al and Al-20Ti coatings was successfully simulated by using an artificial neural network model by supplying experimental data as a target.