The bonded MoS_(2)solid lubricant coating is an effective measure to mitigate the fretting wear of AISI 1045 steel.In this work,the amino functionalized MoS_(2)was protonated with acetic acid to make the MoS_(2)positi...The bonded MoS_(2)solid lubricant coating is an effective measure to mitigate the fretting wear of AISI 1045 steel.In this work,the amino functionalized MoS_(2)was protonated with acetic acid to make the MoS_(2)positively charged.The directional arrangement of protonated MoS2 in the coating was achieved by electrophoretic deposition under the electric field force.The bonded directionally aligned MoS_(2)solid lubricant coating showed high adaptability to various loads and excellent lubrication performance under all three working conditions.At a load of 10 N,the friction coefficient and wear volume of the coating with 5 wt%protonated MoS_(2)decreased by 20.0%and 37.2%compared to the pure epoxy coating,respectively,and by 0.07%and 16.8%than the randomly arranged MoS_(2)sample,respectively.The remarkable lubricating properties of MoS_(2)with directional alignment were attributed to its effective load-bearing and mechanical support,barrier effect on longitudinal extension of cracks,and the formation of a continuous and uniform transfer film.展开更多
Carbon nanoparticle coatings on laser-patterned stainless-steel surfaces present a solid lubrication system where the pattern's recessions act as lubricant-retaining reservoirs.This study investigates the influenc...Carbon nanoparticle coatings on laser-patterned stainless-steel surfaces present a solid lubrication system where the pattern's recessions act as lubricant-retaining reservoirs.This study investigates the influence of the structural depth of line patterns coated with multi-walled carbon nanotubes(CNTs)and carbon onions(COs)on their respective potential to reduce friction and wear.Direct laser interference patterning(DLIP)with a pulse duration of 12 ps is used to create line patterns with three different structural depths at a periodicity of 3.5μm on AISI 304 steel platelets.Subsequently,electrophoretic deposition(EPD)is applied to form homogeneous carbon nanoparticle coatings on the patterned platelets.Tribological ball-on-disc experiments are conducted on the as-described surfaces with an alumina counter body at a load of 100 mN.The results show that the shallower the coated structure,the lower its coefficient of friction(COF),regardless of the particle type.Thereby,with a minimum of just below 0.20,CNTs reach lower COF values than COs over most of the testing period.The resulting wear tracks are characterized by scanning electron microscopy,transmission electron microscopy,and energy-dispersive X-ray spectroscopy.During friction testing,the CNTs remain in contact,and the immediate proximity,whereas the CO coating is largely removed.Regardless of structural depth,no oxidation occurs on CNT-coated surfaces,whereas minor oxidation is detected on CO-coated wear tracks.展开更多
High-temperature solid lubricants play a significant role in the hot metal forming process.However,preparing high-temperature solid lubricant is formidably challenging due to the stern working conditions.Here we succe...High-temperature solid lubricants play a significant role in the hot metal forming process.However,preparing high-temperature solid lubricant is formidably challenging due to the stern working conditions.Here we successfully develop a new type of eco-friendly high-temperature graphite-based solid lubricant by using amorphous silica dioxide,aluminum dihydrogen phosphate,and solid lubricant graphite.The solid lubricating coating exhibits excellent tribological properties with a very low friction coefficient and good wear protection for workpiece at high temperature under the air atmosphere.An array of analytical techniques reveals the existence of solid lubricant graphite in the lubricating coating after the high-temperature friction test.A synergistic effect between the protective surface film and the solid lubricant graphite is proposed to account for such superior lubricating performance.This work highlights the synergistic effect between the protection layer and the lubricant graphite and further provides the insight in designing the high-temperature solid lubricant.展开更多
Transition metal di-chalcogenides MX2 （X= S, Se, Te; and M = W, Mo, Nb, Ta） are one kind of solid lubricant materials that have been widely used in industry. The lubricant properties of such lubricant coatings are d...Transition metal di-chalcogenides MX2 （X= S, Se, Te; and M = W, Mo, Nb, Ta） are one kind of solid lubricant materials that have been widely used in industry. The lubricant properties of such lubricant coatings are dependent not only on microstructure, orientation, morphology, and composition of the coatings, but also on the substrate, the interface between substrate and lubricant coatings, and the specific application environment. In this review, the effects of parameters on tribological properties of such kind of lubricant coatings were summarized. By comparing advantages and disadvantages of those coatings, the special treatments such as doping, structural modulation and post-treatment were suggested, aiming to improve the tribologicai performance under severe test conditions （e.g. high temperature, oxidizing atmosphere or humid condition）.展开更多
基金the financial support of National Natural Science Foundation of China(Nos.52075458 and U2141211)Sichuan Science Foundation for Distinguished Young Scholars(No.2023NSFSC1957)the Analytical and Testing Center of Southwest Jiaotong University for support of the scanning electron microscopy(SEM)and Raman measurements.
文摘The bonded MoS_(2)solid lubricant coating is an effective measure to mitigate the fretting wear of AISI 1045 steel.In this work,the amino functionalized MoS_(2)was protonated with acetic acid to make the MoS_(2)positively charged.The directional arrangement of protonated MoS2 in the coating was achieved by electrophoretic deposition under the electric field force.The bonded directionally aligned MoS_(2)solid lubricant coating showed high adaptability to various loads and excellent lubrication performance under all three working conditions.At a load of 10 N,the friction coefficient and wear volume of the coating with 5 wt%protonated MoS_(2)decreased by 20.0%and 37.2%compared to the pure epoxy coating,respectively,and by 0.07%and 16.8%than the randomly arranged MoS_(2)sample,respectively.The remarkable lubricating properties of MoS_(2)with directional alignment were attributed to its effective load-bearing and mechanical support,barrier effect on longitudinal extension of cracks,and the formation of a continuous and uniform transfer film.
基金financial support by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)within the project MU 959/47-1Furthermore,the authors gratefully acknowledge funding in the ZuMat projectsupported by the State of Saarland from the European Regional Development Fund(Europäischer Fonds für Regionale Entwicklung,EFRE).P.Grützmacher and C.Gachot would like to thank the Government of Lower Austria(WST3)for financially supporting the endowed professorship tribology at the TU Wien.V.Presser thanks Eduard Arzt(INM)for his continuing support.
文摘Carbon nanoparticle coatings on laser-patterned stainless-steel surfaces present a solid lubrication system where the pattern's recessions act as lubricant-retaining reservoirs.This study investigates the influence of the structural depth of line patterns coated with multi-walled carbon nanotubes(CNTs)and carbon onions(COs)on their respective potential to reduce friction and wear.Direct laser interference patterning(DLIP)with a pulse duration of 12 ps is used to create line patterns with three different structural depths at a periodicity of 3.5μm on AISI 304 steel platelets.Subsequently,electrophoretic deposition(EPD)is applied to form homogeneous carbon nanoparticle coatings on the patterned platelets.Tribological ball-on-disc experiments are conducted on the as-described surfaces with an alumina counter body at a load of 100 mN.The results show that the shallower the coated structure,the lower its coefficient of friction(COF),regardless of the particle type.Thereby,with a minimum of just below 0.20,CNTs reach lower COF values than COs over most of the testing period.The resulting wear tracks are characterized by scanning electron microscopy,transmission electron microscopy,and energy-dispersive X-ray spectroscopy.During friction testing,the CNTs remain in contact,and the immediate proximity,whereas the CO coating is largely removed.Regardless of structural depth,no oxidation occurs on CNT-coated surfaces,whereas minor oxidation is detected on CO-coated wear tracks.
基金The work is financially supported by the National Key Research and Development Program(No.2018 YFB2002204)the National Natural Science Foundation of China(Grant Nos.51925506 and 51527901).
文摘High-temperature solid lubricants play a significant role in the hot metal forming process.However,preparing high-temperature solid lubricant is formidably challenging due to the stern working conditions.Here we successfully develop a new type of eco-friendly high-temperature graphite-based solid lubricant by using amorphous silica dioxide,aluminum dihydrogen phosphate,and solid lubricant graphite.The solid lubricating coating exhibits excellent tribological properties with a very low friction coefficient and good wear protection for workpiece at high temperature under the air atmosphere.An array of analytical techniques reveals the existence of solid lubricant graphite in the lubricating coating after the high-temperature friction test.A synergistic effect between the protective surface film and the solid lubricant graphite is proposed to account for such superior lubricating performance.This work highlights the synergistic effect between the protection layer and the lubricant graphite and further provides the insight in designing the high-temperature solid lubricant.
文摘Transition metal di-chalcogenides MX2 （X= S, Se, Te; and M = W, Mo, Nb, Ta） are one kind of solid lubricant materials that have been widely used in industry. The lubricant properties of such lubricant coatings are dependent not only on microstructure, orientation, morphology, and composition of the coatings, but also on the substrate, the interface between substrate and lubricant coatings, and the specific application environment. In this review, the effects of parameters on tribological properties of such kind of lubricant coatings were summarized. By comparing advantages and disadvantages of those coatings, the special treatments such as doping, structural modulation and post-treatment were suggested, aiming to improve the tribologicai performance under severe test conditions （e.g. high temperature, oxidizing atmosphere or humid condition）.
