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The tribological performances of Cr/GLC film coupling with Si 3 N 4 , SiC, WC, Al 2 O 3 and ZrO 2 were comparatively studied in seawater. Results indicated that the Cr/GLC film coupling with different ceramic counterparts exhibited different friction behaviors, which was closely related to the mechanical performances of mating ceramics. Meanwhile, the tribo-chemical products between the Cr/GLC film and ceramics also played an important role in improving the tribological performances. Friction coefficient and wear rate of the Cr/GLC film sliding against Si 3 N 4 were lower than others, which indicated that the Cr/GLC film coupled to Si 3 N 4 ceramic exhibited optimum tribological performance in seawater. [ABSTRACT FROM AUTHOR]

CrCN coatings were deposited using the multi-arc ion plating with different C 2 H 2 flow rates. Microstructures, mechanical and tribological performances were systematically investigated. The results showed that the peak intensity correlated to Cr 7 C 3 crystal phase became stronger when the flow rates increased from 0 to 15 sccm, whereas, it was decreased when the C 2 H 2 flow rate increased to 30 sccm. The hardness increased to 32.5 GPa due to formation of Cr 7 C 3 phase and amorphous CN x at 10 sccm. CrCN coatings deposited at 10–15 sccm exhibited a better comprehensive performance, indicating their potential application as a protective coating for tribo-components in seawater. [ABSTRACT FROM AUTHOR]

[Display omitted] • (AlCrWTiMo)N films were deposited via direct current magnetron sputtering. • (AlCrWTiMo)N showed gradient structure from amorphous to nanocrystalline. • The width of amorphous region decreased with increase of substrate temperature. • The wear mechanisms of (AlCrWTiMo)N were mainly abrasive with less fatigue. The (AlCrWTiMo)N films were deposited at different substrate temperatures by magnetron sputtering. The microstructures, mechanical properties and tribological performances of the (AlCrWTiMo)N films were investigated. Results showed that the deposition rate and nitrogen content of the film decreased slightly with the increase of the substrate temperature. From the interlayer surfaces to the film surfaces, the films showed gradient structures, which gradually transformed from amorphous to nanocrystalline. With the increase of the substrate temperature, the width of the amorphous region decreased, and the width of the nanocrystalline region increased. The top nanocrystalline regions were typical face-centered cubic (FCC) structures. The grain size and surface roughness of the film decreased gradually with the increase of the substrate temperature. The critical load (L C1), hardness and elastic modulus of the film increased first and then decreased, and reached the maximum value when the substrate temperature was 200 ℃, which were 16.06 N, 24.5 GPa and 263 GPa, respectively. The friction coefficient and wear rate of the film decreased first and then increased, and reached the minimum value at substrate temperature 200℃, which were 0.71 and 1.1 × 10−5 mm3/Nm, respectively. The wear mechanism of film was mainly abrasive wear accompanied by mild fatigue wear. [ABSTRACT FROM AUTHOR]

The a-C:H films with plasma-induced in-situ transition layer were fabricated on Polyether ether ketone (PEEK) substrates by continuous acetylene plasma treatment, using plasma-enhanced chemical vapor deposition (PECVD) method. Microstructure, chemical bonding state, mechanical and tribological properties of the as-fabricated a-C:H and Cr/a-C:H films were systematically investigated. Based on these, a self-consistent in-situ growth mechanism is discussed in detail. Results show that the a-C:H films with plasma-induced in-situ transition layer endows the treated PEEK substrates high hardness, toughness and adhesion strength. In addition, the interaction of in-situ transition layer and amorphous enhanced phase show better load-bearing capacity in the scratch and tribological test. The failure mechanism of scratch test is proposed and wear mechanisms in vacuum, air and seawater environment are analyzed. Importantly, this novel plasma-induced in-situ transition layer structure is a further development of the concept of gradient coatings in its application to polymers. • An in-situ growing a-C:H film was fabricated on PEEK substrate using PECVD technique. • The formation of in-situ transition layer enhances film-substrate adhesion. • In-situ growth mechanism of a-C:H film on PEEK surface was revealed. • The a-C:H coating on PEEK exhibits the mechanical and tribological adaptability. [ABSTRACT FROM AUTHOR]

• a-C coatings were in-situ grown on ethylene-propylene copolymer (EPC) substrates. • The in-situ growth mechanism of a-C coatings on polymer surface was revealed. • In-situ transition layer endows strong adhesion of a-C coating on EPC substrates. • The possible wear mechanism of a-C coatings on polymer substrates was presented. Surface of ethylene-propylene copolymer (EPC) plastic was continuously treated by carbon plasma in a direct-current magnetron sputtering deposition (DC-MSD) system. Microstructure evolution of the polymer surface with different treating time was analyzed by Diffusive Reflectance infrared Fourier Transform (DRIFT) spectroscopy, Raman Spectroscopy, X-ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscopy (SEM) and Focus Ion Beam Scanning Electron Microscopy (FIB-SEM), respectively. The adhesion strength and tribological performance were measured by scratch tester and reciprocating ball-on-disc tribometer. Results showed that the bombardment of energetic plasma was capable of activating the surface polymer substrate, which could induce an in-situ transformation from organic carbon to inorganic carbon of the surface layer, following with an epitaxial growth of amorphous carbon upon the in-situ transition layer with the continuous treatment of carbon plasma. This kind of in-situ growing a-C coating on polymer including the in-situ transformation of top layer and the epitaxial growth on in-situ transition layer endow the weak substrate an excellent protective surface with strong adhesion, which exhibited much lower friction and wear. The possible wear mechanism of a-C coatings on polymer substrates was also presented. [ABSTRACT FROM AUTHOR]

In this study, the Ti/(Cu, MoS 2)-DLC coatings with various Cu contents were prepared on stainless steel substrates by RF/DC magnetron sputtering technique. The effects of Cu content on microstructure, mechanical, tribological, anticorrosion and antifouling properties of coating were systematically investigated. Results showed that the addition of Cu could modify the composited microstructure and enhance the multi-functional protection of Ti/(Cu, MoS 2)-DLC coating. As the increase of Cu content, the surface roughness and sp2/sp3 ratio of Ti/(Cu, MoS 2)-DLC coating presented an uptrend. Meanwhile, the hardness and elastic modulus of coating gradually displayed a downtrend. Overall, the coating with 7.6 at.% Cu exhibited optimal multi-functional protective effects in marine environment, including self-lubrication, wear-resistance, anticorrosion and antifouling ability. • Multi-functional Ti/(Cu, MoS 2)-DLC coatings with different Cu content were deposited via RF/DC magnetron sputtering technique. • The surface roughness and sp2 / sp3 ratio values gradually increased with the increase of Cu content. • The tribological, anticorrosion and antifouling properties of Ti/(Cu, MoS 2)-DLC coatings could be tailored by Cu doping. [ABSTRACT FROM AUTHOR]