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In the study, the hydrogen‐free diamond‐like carbon (DLC) coating was deposited on the surface of the Co‐Cr‐Mo alloy. Pin‐on‐plate tribotests were performed for the DLC‐coated CoCrMo specimen against un‐doped CoCrMo alloy under bovine serum albumin (BSA), NaCl solution, and distilled water. Results showed that the average coefficient of friction (COF) of the mating system was 0.08 under NaCl and 0.07 under distilled water, respectively. However, the dynamic COF under BSA lubrication was prone to increasing with testing time, and the average COF got to 0.12. The wear morphology of the pin was covered by the carbon transfer layer without BSA lubrication, and the formation of the transfer layer was a dynamic evolution process as wear debris adhesion, continuous transferring, and delamination. Oppositely, the transfer layer was inhibited under BSA lubrication due to the adsorption of the protein layer on the contact interface. [ABSTRACT FROM AUTHOR]

A layer-by-layer deposition technique with grafting chitosan on the Co-Cr-Mo alloy was developed. The performance of tribology and biocompatibility were investigated under simulated conditions. Wettability of coating surface was super hydrophilic and the surface was in positive charge under the neutral solution, which was favored in water-based lubricating and adhesion of cells. By pin-on-disk tests, the chitosan coating surface exhibited lower friction coefficient under various sliding speed as compared with the uncoated substratum. A wear rate of 1.1 × 10 −7 mm 3 /Nm was detected, which was only one seventh of uncoated surfaces. Hypothetically illuminating the mechanism of antifriction is able to lead for better wear resistance. Co-culturing with osteoblast cells showed that coating had good benefits in the proliferation of osteoblast cells. [ABSTRACT FROM AUTHOR]

Ship hulls and subsea equipment are plagued by current resistance, seawater particles impact, corrosion and other challenges in the ocean. Consequently, developing sustainable nontoxic antifouling coatings is highly urgent. Discoveries from nature have inspired us to design high-efficiency, environmentally friendly, and cost-effective antifouling coatings. In the study, a strategy of combining microstructures and Benzotriazole (BTA) was proposed through constructing shark skin shield scale structure, which improved drag reduction and increased abrasion resistance as well. On the synergistic effect of BTA as corrosion inhibitor, the friction coefficient of the coating was significantly reduced and the anti-corrosion performance was greatly improved. Compared to the smooth pure epoxy coating, the anti-corrosion performance and the drag reduction rate of Texture-BTA-3 % coating was improved by 30 % and about 10 %, respectively. Furthermore, the effect of coating structure on corrosion resistance was revealed. This investigation will broaden the applications in marine navigation with the favorable performance. [Display omitted] • A method for preparing epoxy resin with imitating sharkskin surface texture has been proposed. • Verified the influence of the coating texture on anti-corrosion performance. • Drag reduction rate of the designed coating in water is about 10 %. • The friction coefficient is reduced of 40 % during friction process. [ABSTRACT FROM AUTHOR]

Abstract: Surface wettability behaviors of three kinds of laser textured Co–Cr–Mo alloy surfaces (arrays of circular, triangular and square shape dimples) were evaluated in aqueous bovine serum albumin (BSA) solution. The tribological properties of laser textured Co–Cr–Mo alloy were investigated by pin–on–disc reciprocating tribometer under BSA lubrication. The wetting surfaces ranging from superhydrophilic (CA=21.5°) to superhydrophobic (CA=142.2°) were obtained by dual/combined surface modification including laser surface texturing (LST) and further fluoro-alkyl silane (FAS). It was found that surface wettability behaviors of Co–Cr–Mo alloy surfaces were closely related to their tribological behaviors in BSA solution. Results showed that the contact angle of circular dimple was the most stable, sliding time of the friction pair reaching steady state stage was shortest and coefficient of friction was minimum among three regular layout shapes of dimples during the tribological tests. It suggests that the combined surface modification of LST and FAS is a promising method to improve the tribological performances and prolong the service life of Co–Cr–Mo orthopedic implants. [Copyright &y& Elsevier]

MXene, a two-dimensional (2D) material consisting of Ti 3 C 2 T x , has demonstrated significant potential for numerous applications, particularly in the areas of corrosion and wear resistance to protect metals. In this study, we reported the facile preparation of MXene/epoxy resin (EP) coatings through blending, which was successfully confirmed by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). With the lubrication of oleic acid (OA), an EP coating containing 1 wt% MXene exhibited superlubricity with a remarkably low coefficient of friction (COF) of 0.008. Furthermore, compared to the pristine substrate, the coating achieved an impressive reduction in the wear rate of 99.73 %. Under simulated seawater conditions, the coating demonstrated an exceptional corrosion protection efficiency (PE) of 99.38 %, which was attributed to the corrosion inhibition effect of MXene. The observed superlow friction was primarily attributed to the synergistic effects of a tribo-film of OA, the presence of the MXene film, and the improved mechanical properties of the EP coating due to the incorporation of MXene. Our study highlighted the potential of MXene as a protective material in long-term marine applications. • Coatings with both wear resistance and corrosion resistance were prepared. • The prepared coatings could enter the superlubricity regime. • MXene in E51 coating effectively improved the corrosion resistance. • Investigated the potential of MXene as a protective material for long-term marine applications. [ABSTRACT FROM AUTHOR]