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Three species of diamond-like carbon (DLC) film were systematically examined in NaCl solution for their anticorrosion properties. Si&N&H-DLC has better electrochemical characteristics and salt spray corrosion testing results than the substrate and two species DLC films in NaCl solution. Due to the successive growth of Si, N, and H-DLC, there is a well-bonded Si–N interface and the formation of Si oxides. The Si&N&H-DLC film exhibits extremely high charge transfer resistance, exceeding 106 Ω/cm2. A salt spray test shows that the Si&N&H-DLC film presents a lower rate in NaCl solution in comparison to the substrate and the other two species of DLC films. As a result, the Si&N&H-DLC film significantly improved the corrosion performance of the substrate. [ABSTRACT FROM AUTHOR]

In this study, the superhydrophobic epoxy resin coating with siloxane-modified carbon nanotubes was prepared. Hydroxylated multi-walled carbon nanotubes (HMWCNTs) were modified with siloxane to make them superhydrophobic, which were mixed with epoxy resin to prepare an excellent superhydrophobic coating on the surface of AH36 carbon steel. Highly silanized HMWCNTs (HSHMWCNTs) were added to hydrophobic isobutyl groups and amino groups that can bond with epoxy resin. The results show that the water contact angle (WCA) of HSHMWCNTs is >170°. The coating has a WCA of 157.2° and a water sliding angle of 6° when the addition of the HSHMWCNTs reaches 70 %. The coating has excellent self-cleaning properties and remains superhydrophobicity under tape-peeling for 90 times. When the coating has a superhydrophobic effect, there is an air layer on the surface, improving the corrosion resistance of the coating. [Display omitted] • Groups bonding to the coating are attached on CNTs to improve durability. • Stirring or ultrasonic superhydrophobic coatings are characterized. • They remained superhydrophobicity under tape-peeling for 90 times. • Fluoride use was eliminated. [ABSTRACT FROM AUTHOR]

PEMFC are considered to be the most promising for automotive energy because of their good working effect, low temperature, high efficiency, and zero pollution. Stainless steel as a PEMFC bipolar plate has unparalleled advantages in strength, cost, and processability, but it is easy to corrode in a PEMFC working environment. In order to improve the corrosion resistance, the surface modification of 316L stainless steel is a feasible solution for PEMFC bipolar plates. In the present study, the plasma-nitrided coating and CrNx coating were prepared by the plasma-enhanced balanced magnetron sputtering technology on the 316L stainless steel surface. The microstructures, phase compositions, and corrosion resistance behavior of the coatings were investigated. The corrosion behavior of the prepared plasma-nitrided coating and CrNx coating was investigated by potentiodynamic polarization, potentiostatic polarization, and electrochemical impedance spectroscopy (EIS) in both cathodic and anodic environments. The experimental results show that corrosion resistance of the CrNx coating was better than the plasma-nitrided coating. It was indicated that the technology process of nitriding first and then depositing Cr was better than nitriding only. [ABSTRACT FROM AUTHOR]

For degradable magnesium alloy stents, excellent corrosion resistance and rapid endothelialization are two essential properties. In this paper, we plan to use a copper-loaded chitosan coating to accelerate the endothelialization process of the stent, which not only improves the biocompatibility of the magnesium alloy stent, but also its corrosion resistance by improving the service environment in vivo. Copper is an impurity in magnesium alloys, so how copper-containing coatings affect the corrosion resistance of magnesium alloy stents is the focus of this paper. The corrosion properties of the material were characterized by electrochemical experiments, immersion experiments, and in vitro cellular experiments characterized the effect of the copper-loaded coating on endothelial cells. The results showed that the I corr of the copper-loaded chitosan coated sample and the I corr of the unloaded copper chitosan coated sample were both in the order of 10−8, and the decrease of the corrosion resistance of the magnesium alloy by the copper-containing chitosan composite coating was not significant, and it still had a protective effect on the magnesium alloy substrate. During the immersion process, magnesium and copper ions were slowly released, followed by the hydrogen released. In addition, the weight loss rate of different coated samples presented the tendency of slower at inital, faster at last, and the weight loss rate of 0.041% for the copper-loaded chitosan coated sample was not significantly different from that of 0.035% for the unloaded copper coating group, after 28 days of immersion. The in vitro degradation products of the copper-loaded composite coating on the surface of magnesium alloy were also analyzed by XRD and EPMA, which included M g (O H) 2 , M g 3 (P O 4) 2 and C a 3 (P O 4) 2 ; in addition the degradation process was analyzed. The cellular experiments results showed that the copper-loaded magnesium alloy had a proliferation rate of 243.0% for endothelial cells, which indicated that the copper-loaded coating could endow magnesium alloy stent a good biofunctional properties. • For endowing biofunction to Mg alloy stent, a copper-loaded chitosan coating is prepared on its surface for the first time. • The copper ion loaded to coating does not effect corrosion resistance of magnesium alloys significantly. • It is inferred that copper-loaded coating endows the magnesium alloy material excellent endothelialization potential. • The degradation mechanism of magnesium alloy treated by copper-loaded coating is elucidated. [ABSTRACT FROM AUTHOR]