To enhance the tribological performance of the conventional TiCrN coating, the MoSsub.2–TiCr coatings are deposited onto the TiCrN layer by magnetron sputtering. In general, the MoSsub.2 is ...implemented to enhance the friction reduction performance of the TiCrN coating, while the Ti and Cr are doped to increase the density of the structure and prevent MoSsub.2 from oxidizing. The results reveal that with an increase in the content of Ti and Cr in the MoSsub.2–TiCr top layer, the hardness and the coating–substrate adhesion force of the composite coating increase, respectively, due to the compact top layer. Further, the optimized Ti and Cr doping in the MoSsub.2 top layer greatly enhances the tribological properties of the TiCrN/MoSsub.2–TiCr composite coating with a friction coefficient as low as 0.06 and the wear rate is only 6% of the TiCrN coating. The main reason for the excellent tribological properties of the TiCrN/MoSsub.2–TiCr composite coating is probably due to the recrystallization of the MoSsub.2 in the process of wear.
In this article, engineering surface application is introduced as a new concept. The basis of this concept is the understanding that different surface technologies are applied to design of existing ...engineering components but, it is necessary to know that surface engineering would cover only part of the design of the component, the surface treatment to be applied should also be known. This is because, surfaces with a high index of hardening due to deformation, are resistant to severe adhesive wear, abrasion and pickling, but they should not have the same resistance to other types of wear. It means that a correlation must be established between the surface quality and the pickling resistance. In this article, it is shown that the use of high compatibility metallic materials is preferred and that a correlation can be established between the surface quality and the pickling resistance by a simple number. The selection of materials and the methods of obtaining the engineering surfaces for tribological applications, depends to a large extent on the mechanism and particular type of predominant wear. Therefore, the selection of materials resistant to wear will be analyzed depending on the type of wear in question.
In preparing MoSsub.2-based coatings by magnetron sputtering, the working pressure of the vacuum chamber directly affects the number and kinetic energy of sputtering particles, which causes a ...difference in coatings structure and performance. In this paper, MoSsub.2 composite coatings with Ce and Ti binary doping were prepared by unbalanced magnetron sputtering technology, and the variation of composition, structure, and tribological properties of Ce-Ti/MoSsub.2 coatings under different working pressures was studied. The results demonstrated that Ce and Ti doping improves pure MoSsub.2 coatings. The Ce-Ti/MoSsub.2 coatings reached the hardness of 9.02 GPa and the friction coefficient of 0.065 when working pressure was at 0.6 Pa. It was also observed that the deposition efficiency and wear rate reached the optimal value at 0.9 Pa. With the increase of working pressure, the columnar structure of the coating was coarse due to the change of kinetic energy and quantity of particles in the chamber. The intensity of the MoSsub.2 (002) diffraction peak decreased, which eventually led to a poor lubrication effect and aggravated wear. This study provides technical guidance for preparing metal-doped MoSsub.2 composite coatings with excellent mechanical and tribological properties.
Laser cladding Ni60/2.0 wt.%CeOsub.2 self-lubricating anti-wear composite coatings on 35CrMoV steel were thermally treated at 25 °C, 500 °C, 600 °C and 700 °C for 1 h, respectively. The macroscopic ...morphology of composite coatings was characterized by optical microscopy. The evolution of microstructure was studied by scanning electron microscopy. The precipitated phase of the coating was analyzed by X-ray diffractometer. The microhardness and wear properties of the composite coatings were measured by microhardness tester and friction and wear test. The effects of thermal treatment and no thermal treatment on the mechanical properties of the composite coatings were systematically studied by the above experiments. The experimental analysis shows that the main phase composition of Ni60/2.0 wt.%CeOsub.2 composite coating is γ-(Ni, Fe), Crsub.7Csub.3, Crsub.23Csub.6, CrB, CrFeB and Crsub.2Nisub.3. Meanwhile, in XRD, it can be seen that the diffraction peak has shifted to the left and the single diffraction peak is decomposed into double diffraction peaks with the thermal treatment at 700 °C, which indicates that the lattice in the coating phase has a certain distortion. Compared with the coatings without thermal treatment, Ni60 cladding layer has more uniform solute distribution and a denser and more uniform structure after thermal treatment at 700 °C. The laser cladding anti-wear composite coating demonstrates that the wear resistance performance shows the greatest improvement after thermal treatment at 700 °C.
Alsub.xCoCrFeNiTi (x = 0.1, 0.3, 0.6, 1) powders were prepared via mechanical alloying and were used as binders for SPS-produced Ti(C,N)-based cermets. The effects of AlxCoCrFeNiTi binder on phase ...composition, morphology, room-temperature mechanical properties, and oxidation resistance of cermets were studied. The research showed that cermets with Alsub.xCoCrFeNiTi binders exhibited a more homogeneous core-rim structure than cermets with cobalt binders. The Vickers hardness and fracture toughness of cermets with Alsub.xCoCrFeNiTi binders increased with the aluminum molar ratio due to the grain refinement and solid solution strengthening effect of carbonitrides. After static oxidation at 1000 °C, the mass gain of the cermets with Alsub.xCoCrFeNiTi binders changed according to a quasi-parabolic law, and the lowest mass gain was obtained in the cermet with Alsub.0.6CoCrFeNiTi binder. The oxidation kinetics curve of the benchmark cermet with cobalt followed a linear law. The oxidation product of Ti(C,N)-based cermet with cobalt was rich in TiOsub.2, and the Ti(C,N)-based cermets with Alsub.xCoCrFeNiTi binders were transformed into complex oxides, such as NiMoOsub.4, NiWOsub.4, FeMoOsub.4, Fesub.3Tisub.3Osub.9, and Nisub.3TiOsub.7. The oxide layer on the cermet with Alsub.0.6CoCrFeNiTi appeared to be dense and protective, which inhibited the diffusion of oxygen into the cermet and improved the oxidation resistance of the final product.
There is an increasing diffusion of the industry 4. 0 concept today. The fourth industrial revolution, following three other previous industrial revolutions, is considered related to the introduction ...of modern information and communication technologies in production. Tribological concepts are much older than industry. Tribology has always been connected to industrial problems from the birth of industry. It was strongly connected with the previous industrial revolutions and it is surely related to industry 4.0. In this work, the main aspects of the four industrial revolutions and the main evolutions of tribology are firstly reviewed from a historical point of view. The relationships between tribology and industry are described with particular attention to the aspects that relate the modern tribology 4.0 to industry 4.0. Tribology can have in particular a big impact on the industrial needs to reduce losses and wastes, for instance with the development of new tribological components and materials also in connection with electronic smart systems and taking advantage of the information and communication technologies.
The Nordic Symposium on Tribology (NordTrib) is held biennially in one of the Nordic countries: Finland, Sweden, Norway and Denmark. During the years the symposium has grown and it is now much larger ...and more international than it was in 1984. The 17th NordTrib Symposium (Nortrib 2016) was organized in Aulanko, Haxneenlinna, Finland, June 14th-17th, 2016 by the Finnish Society for Tribology and VTT Technical Research Centre of Finland Ltd.
Bsub.4C-particle-reinforced Al (Bsub.4Csub.p/Al) composites are widely used in various areas, e.g., armors, electronic packaging and fuel storage, owing to their several outstanding properties ...including high specific rigidity, excellent wear resistance and light weight. Selective laser melting (SLM) is favored in manufacturing complex components because of its high raw material utilization rate and high efficiency. In this work, a Bsub.4Csub.p/Al composite was successfully synthesized by SLM, and the effects of one of the most important parameters, scanning speed (100-700 mm/s), on the phase composition, density, microhardness and tribological properties of the samples were investigated. The microhardness, relative density and dry-sliding wear resistance of as-prepared Bsub.4Csub.p/Al composites were improved with the decrease in scanning speed, and the sample fabricated at a scanning speed of 100 mm/s exhibited a relative density as high as about 97.1%, and a maximum microhardness of ~180 HVsub.0.1 (approximately six times more than that of the SLM-formed pure Al sample, 31 HVsub.0.1), a minimum wear rate of 4.2 × 10sup.−5 mmsup.3·Nsup.−1·msup.−1 and a corresponding friction coefficient of 0.41. In addition, abrasive wear, adhesive wear and oxidation wear were found to be behind the overall wear behavior of as-prepared Bsub.4Csub.p/Al composites.
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