Improvement on the oxidation resistance and tribological properties of molybdenum disulfide film by doping nitrogen

In this study, epoxy resin (EP) composites were prepared by using molybdenum disulfide (MoS2) and helical carbon nanotubes (H-CNTs) as the antifriction and reinforcing phases, respectively. The effects of MoS2 and H-CNTs on the friction coefficient, wear amount, hardness, and elastic modulus of the composites were investigated. The tribological properties of the composites were tested using the UMT-3MT friction testing machine, non-contact three-dimensional surface profilometers, and nanoindenters. The analytical results showed that the friction coefficient of the composites initially decreased and then increased with the increase in the MoS2 content. The friction coefficient was the smallest when the MoS2 content in the EP was 6%, and the wear amount increased gradually. With the increasing content of H-CNTs, the friction coefficient of the composite material did not change significantly, although the wear amount decreased gradually. When the MoS2 and H-CNTs contents were 6% and 4%, respectively, the composite exhibited the minimum friction coefficient and a small amount of wear. Moreover, the addition of H-CNTs significantly enhanced the hardness and elastic modulus of the composites, which could be applied as materials in high-temperature and high-pressure environments where lubricants and greases do not work.

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Structure, Oxidation Resistance, Mechanical, and Tribological Properties of N- and C-Doped Ta-Zr-Si-B Hard Protective Coatings Obtained by Reactive D.C. Magnetron Sputtering of TaZrSiB Ceramic Cathode

Coatings ◽

10.3390/coatings10100946 ◽

2020 ◽

Vol 10 (10) ◽

pp. 946

Author(s):

Ph. V. Kiryukhantsev-Korneev ◽

A. D. Sytchenko ◽

S. A. Vorotilo ◽

V. V. Klechkovskaya ◽

V. Yu. Lopatin ◽

...

Keyword(s):

Magnetron Sputtering ◽

Oxidation Resistance ◽

Tribological Properties ◽

Protective Coatings ◽

Elastic Recovery ◽

Protective Film ◽

X Ray Diffraction ◽

Energy Dispersion Spectroscopy ◽

X Ray ◽

Mechanical And Tribological Properties

Coatings in the Ta-Zr-Si-B-C-N system were produced by magnetron sputtering of a TaSi2-Ta3B4-(Ta,Zr)B2 ceramic target in the Ar medium and Ar-N2 and Ar-C2H4 gas mixtures. The structure and composition of coatings were studied using scanning electron microscopy, glow discharge optical emission spectroscopy, energy-dispersion spectroscopy, and X-ray diffraction. Mechanical and tribological properties of coatings were determined using nanoindentation and pin-on-disk tests using 100Cr6 and Al2O3 balls. The oxidation resistance of coatings was evaluated by microscopy and X-ray diffraction after annealing in air at temperatures up to 1200 °C. The reactively-deposited coatings containing from 30% to 40% nitrogen or carbon have the highest hardness up to 29 GPa and elastic recovery up to 78%. Additionally, coatings with a high carbon content demonstrated a low coefficient of friction of 0.2 and no visible signs of wear when tested against 100Cr6 ball. All coatings except for the non-reactive ones can resist oxidation up to a temperature of 1200 °C thanks to the formation of a protective film based on Ta2O5 and SiO2 on their surface. Coatings deposited in Ar-N2 and Ar-C2H4 demonstrated superior resistance to thermal cycling in conditions 20-T−20 °C (where T = 200–1000 °C). The present article compares the structure and properties of reactive and “standard-inert atmosphere” deposited coatings to develop recommendations for optimizing the composition.

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Tribological performance of AlCrN–MoS2/PTFE hard-lubricant composite coatings

Proceedings of the Institution of Mechanical Engineers Part J Journal of Engineering Tribology ◽

10.1177/1350650119878564 ◽

2019 ◽

Vol 234 (9) ◽

pp. 1355-1367

Author(s):

Yang Lu ◽

Jianxin Deng ◽

Wenlong Song ◽

Xuemu Li ◽

Liangliang Zhang ◽

...

Keyword(s):

Friction Coefficient ◽

Molybdenum Disulfide ◽

Tribological Properties ◽

Adhesive Strength ◽

Wear Track ◽

Composite Coatings ◽

Thermal Spraying ◽

Tribological Performance ◽

Ptfe Composite ◽

Spraying Method

In order to improve the tribological performance of the physical vapor-deposited AlCrN coatings, molybdenum disulfide (MoS2)/poly tetra fluoroethylene (PTFE) coatings were fabricated on the AlCrN coatings surface through the thermal spraying method. The microstructure, adhesive strength, hardness, and tribological properties were investigated. Reciprocating sliding tests against SiC ball were executed with a ball-on-plate tribometer. Results showed that the adhesive strength between the AlCrN–MoS2/PTFE composite coatings and substrate was increased by about 15% compared with single AlCrN coatings. Compared with the single MoS2/PTFE coatings, the hardness of the AlCrN–MoS2/PTFE composite coatings surface was increased by about 15%. The MoS2/PTFE layer can availably reduce the friction coefficient of single AlCrN layer, and the AlCrN–MoS2/PTFE composite coatings exhibited the lowest and the most stable friction coefficient. In addition, the MoS2/PTFE layer existed on the wear track and accumulated on both the sides, which was the main reason that the friction coefficient was still lower compared with the samples without MoS2/PTFE coatings.

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Tribological Properties of Nanolamellar MoS2Doped with Copper Nanoparticles

Journal of Nanomaterials ◽

10.1155/2014/731073 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

Vladimir An ◽

Yuri Irtegov

Keyword(s):

High Temperature ◽

Molybdenum Disulfide ◽

Copper Nanoparticles ◽

Tribological Properties ◽

Electrical Explosion ◽

Elementary Sulfur ◽

Molybdenum Powder ◽

Temperature Synthesis ◽

High Temperature Synthesis ◽

Electrical Explosion Of Wires

This study aimed at examining the tribological properties of nanolamellar molybdenum disulfide doped with copper nanoparticles. Nanolamellar molybdenum disulfide was produced using self-propagating high-temperature synthesis via the reaction between elementary sulfur and nanosized molybdenum powder prepared by electrical explosion of wires. Copper nanoparticles were also prepared by electrical explosion of copper wires. Comparative tribological tests were carried out for nanolamellar and commercial molybdenum disulfides doped with 7 wt.% of copper nanoparticles. It was demonstrated that doping copper nanoparticles additives reduce wear of the friction body when using both commercial and nanolamellar molybdenum disulfide.

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