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The design of robust and durable ultra‐lubricated surfaces having an efficient corrosion resistance ability is concerned with practical applications. Here a new optimized strategy to significantly improve the performance of ultra‐lubricated surfaces by injecting slippery nanofluids into the hierarchical surfaces (SNHSs) is proposed. Herein, cobalt–nickel hierarchical surfaces reinforced by micro SiO2 particles are achieved on carbon steel substrate by electrochemical deposition and the functionalized nanofluids are injected into the hierarchical structure. Compared with nanostructured ultra‐lubricated surfaces, SNHSs exhibit better lubricity and corrosion resistance when subjected to water flow shear for more than 20 h. The tribo‐electrochemical tests are introduced to demonstrate that the SNHS has a lower coefficient of friction (0.39), more shallow wear marks (5 μm), and more complete surface morphology by directly comparing the wear resistance and self‐healing ability. The hierarchical substrate has more advantages than the nanostructured substrate in the practical application of ultra‐lubricated surface. Furthermore, the SNHS with robust mechanical durability can be a promising alternative technique for corrosion protection. [ABSTRACT FROM AUTHOR]

A zinc-aluminum (Zn-Al) composite coating was prepared on a 304 stainless steel surface by dip coating and a thermal sintering method. The microstructure and the phase composition of the composite coating were analysed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Open-circuit potential (OCP), potentiodynamic polarisation curves and electrochemical impedance spectroscopy (EIS) were used to study the electrochemical properties of the coating. The results demonstrate that the Zn-Al composite coating can effectively decrease the corrosion rate of stainless steel, providing an excellent way to solve the corrosion problem in harsh environments. [ABSTRACT FROM AUTHOR]

The long-term durability for two kinds of Co–Ni-based robust coatings, the Co–Ni super-hydrophobic (Co–Ni SHPB) coating and Co–Ni/WC super-hydrophobic (Co–Ni/WC SHPB) coating, was analyzed through an immersion test in 3.5 wt.% NaCl solution. The evolution of their surface properties was characterized by scanning electron microscope (SEM) images, energy-dispersive spectrometry (EDS), a wettability measurement and X-ray photoelectron spectrometer (XPS), and the evolution of anti-corrosion mechanisms was evaluated with electrochemical measurements. The results show that as-prepared two kinds of robust coatings display a good long-term durability, with the Co–Ni SHPB coating and Co–Ni/WC SHPB coating losing their super-hydrophobicity after being immersed for more than 10 days. Additionally, both kinds of coatings present efficient corrosion protection even after long-term immersion. [ABSTRACT FROM AUTHOR]

In this work, different cationic surfactants with various aliphatic and aromatic ammonium cations were used to prepare inhibitor coatings and were characterized by different techniques such as IR spectroscopy and NMR. The inhibitor coatings were prepared by electrografting on the steel surface and their anticorrosion properties were evaluated in different media (HCl, H2SO4 and NaCl solutions). The electrochemical potentiodynamic polarization technique was used to study the inhibition efficiency of the prepared coatings. The dependence of the wetting properties of the electrografted layer and its homogeneity on the molecular structure of the prepared surfactants was studied. Particular attention was paid to the relationship between the properties of these surfactants in terms of critical micellar concentration, packing and wetting, and the anti-corrosion efficiency of their coatings. In this paper, we discuss the synergistic inhibition effect and the anticorrosion efficiency. [ABSTRACT FROM AUTHOR]

In this study, the super-hydrophobic Ni–Co/Cu composite coating was fabricated on carbon steel substrate by electrochemical deposition, chemical oxidation and surface modification. Their surface morphologies, structures and wetting properties were studied by SEM, XRD and contact angle measurements. The results shows that the as-prepared coating has super-hydrophobic property with a water contact angle of 158.61°. After the immersion test in seawater for 350 h, the super-hydrophobic Ni–Co/Cu composite coating shows a good durability of the hydrophobic property. The electrochemical tests indicate that the as-prepared super-hydrophobic coating exhibits excellent corrosion protection for carbon steel compared with Ni–Co and Ni–Co/Cu coating. This study developed a novel approach to improve the corrosion resistance of carbon steel. • A new kind of Ni–Co/Cu super-hydrophobic coating was fabricated. • A new way to improve the performance of Ni–Co coating was shown. • The composite coating exhibits good superhydrophobic properties during long-term seawater immersion. [ABSTRACT FROM AUTHOR]