Influence Of MoS2 Research Articles

The influence of MoS2 and SiC reinforcement on enhancing the tribological and hardness of aluminium matrix (Al6061-T6) hybrid composites using Taguchi’s method

The influence of MoS2 and SiC reinforcement on enhancing the tribological and hardness of aluminium matrix (Al6061-T6) hybrid composites using Taguchi’s method

Influence of MoS2 and graphite-reinforced nanofluid-MQL on surface roughness, tool wear, cutting temperature and microhardness in machining of Inconel 625

Influence of MoS2 and graphite-reinforced nanofluid-MQL on surface roughness, tool wear, cutting temperature and microhardness in machining of Inconel 625

Remote Plasma-Induced Synthesis of Self-Assembled MoS2/Carbon Nanowall Nanocomposites and Their Application as High-Performance Active Materials for Supercapacitors.

The objective of this study is to investigate the synthesis and influence of MoS2 on carbon nanowalls (CNWs) as supercapacitor electrodes. The synthesis of MoS2 on CNW was achieved by the introduction of hydrogen remote plasma from ammonium tetrathiomolybdate (ATTM) without deterioration of the CNWs. The topographical surface structures and electrochemical characteristics of the MoS2–CNW composite electrodes were explored using two ATTM-dispersed organic solvents—acetonitrile and dimethylformamide (DMF). In this study, CNW and MoS2 were synthesized using an electron cyclotron resonance plasma. However, hydrogen radicals, which transform ATTM into MoS2, were provided in the form of a remote plasma source. The electrochemical performances of MoS2–CNW hybrid electrodes with various morphologies—depending on the solvent and ATTM concentration—were evaluated using a three-electrode system. The results revealed that the morphology of the synthesized MoS2 was influenced by the organic solvent used and affected both the electrochemical performance and topographical characteristics. Notably, considerable enhancement of the specific capacitance was observed for the MoS2 with open top edges synthesized from DMF. These encouraging results may motivate additional research on hybrid supercapacitor electrodes and the rapid synthesis of MoS2 and other transition metal dichalcogenides.

Entropy generation analysis of nanoliquid flow through microchannel considering heat source and different shapes of nanoparticle

PurposeThis paper aims to focus on the steady state flow of nanoliquid through microchannel with the aid of internal heat source and different shapes of nanoparticle. The influence of MoS2 and TiO2 particles of nano size on flow and thermal fields is examined. The governing equations are modelled and then solved numerically. The obtained physical model is nondimensionalized using dimensionless quantities. The nondimensional equations are treated with numerical scheme. The outcome of the current work is presented graphically. Diverse substantial quantities such as entropy generation, Bejan number and Nusselt number for distinct parameters are depicted through graphs. The result established that nanoparticle of blade shape acquires larger thermal conductivity. Entropy analysis is carried out to explore the impact of various parameters such as nanoparticle volume fraction, magnetic parameter, radiation parameter and heat source parameter.Design/methodology/approachThe resultant boundary value problem is converted into initial value problem using shooting scheme. Then the flow model is resolved using Runge-Kutta-Fehlberg-Fourth-Fifth order technique.FindingsIt is emphasized that entropy generation for the fluid satisfies N(ζ)(TiO2−water) > N(ζ)(MoS2−water). In addition to this, it is emphasized that N(ζ)sphere > N(ζ)brick > N(ζ)cylinder > N(ζ)platelet > N(ζ)blade. Also, it is obtained that blade-shaped nanoparticle has higher thermal conductivity for both MoS2 and TiO2.Originality/valueShape effects on Molybdenum disulphide and TiO2 nanoparticle in a microchannel with heat source is examined. The analysis of entropy shows that N(ζ)(TiO2−water) > N(ζ)(MoS2−water).

Influence of MoS2 on Activity and Stability of Carbon Nitride in Photocatalytic Hydrogen Production

MoS2/C3N4 (MS-CN) composite photocatalysts have been synthesized by three different methods, i.e., in situ-photodeposition, sonochemical, and thermal decomposition. The crystal structure, optical properties, chemical composition, microstructure, and electron transfer properties were investigated by X-ray diffraction, UV-vis diffuse reflectance spectroyscopy, X-ray photoelectron spectroscopy, electron microscopy, photoluminescence, and in situ electron paramagnetic resonance spectroscopy. During photodeposition, the 2H MoS2 phase was formed upon reduction of [MoS4]2− by photogenerated conduction band electrons and then deposited on the surface of CN. A thin crystalline layer of 2H MoS2 formed an intimate interfacial contact with CN that favors charge separation and enhances the photocatalytic activity. The 2H MS-CN phase showed the highest photocatalytic H2 evolution rate (2342 μmol h−1 g−1, 25 mg catalyst/reaction) under UV-vis light irradiation in the presence of lactic acid as sacrificial reagent and Pt as cocatalyst.

Influence of MoS2 and PTFE in oil film characteristics and tribological performance in EHL point contacts

ABSTRACTThe use of improvers of viscosity index mixed with engine oil to enhance film thickness of lubricant, have been tribologically studied by the optical interferometry technique. The viscosity index improvers (PTFE and MoS2) effect on the mixed engine oil, were experimentally studied and compared with benchmark engine oil without added viscosity improvers. The outcome of the improvers, rolling velocity and contact pressure on the engine oil film formation in a steel ball, loaded on a flat glass surface in point contact, was investigated. The two-beam light source optical interferometry principle was used in this experiment. The Hamrock and Dowson's numerical methods for EHL film formation was compared with the tribo-test results. The base engine oil for this study is SAE 30 while PTFE and MoS2 powdered lubricants were blended with the engine oil. The viscosities of the lubricants ranged from 0.0109 Pa s to 0.255 Pa s. The rolling speed and the loads were distinctly selected between 0.189 m/s to 0.641 m/s and 1 N to 2.6 N, respectively. The steady and rolling state was used to evaluate the stability of the film thickness at contact point. The viscosity improvers were observed to have significant positive influence on the film thickness behaviour.

In-situ construction of hierarchical CdS/MoS2 microboxes for enhanced visible-light photocatalytic H2 production

Exploration of highly active and noble-metal-free photocatalysts for high-efficiency photocatalytic water splitting is of great importance. Herein, a facile and effective in-situ hydrothermal method has been developed for preparation of CdS/MoS2 heterostructures with a unique hollow microbox morphology for visible-light-driven water splitting into H2. The influence of MoS2 is systematically investigated in terms of optical properties and photocatalytic activity of the CdS/MoS2 microboxes by varying the concentration of sodium molybdate. Under visible-light irradiation (λ ≥ 420 nm), the CdS/MoS2 microboxes exhibit superior photocatalytic H2 evolution activity (1.36 mmol/g/h) compared to pure CdS microboxes (0.04 mmol/g/h), corresponding to an apparent quantum yield of 14.5% at 420 nm. Photocatalytic mechanism study proves that the MoS2 nanosheets can serve as a co-catalyst and electron acceptor, for the effective promotion of electron transfer and separation of photogenerated charge carriers from CdS to further stimulate the surface H2 evolution kinetics. Furthermore, the well-defined interior voids, low density and shell permeability of the hierarchical CdS/MoS2 microboxes also contribute to the improvement of the photocatalytic performance.

Influence of MoS2, H3BO3, and MWCNT Additives on the Dry and Lubricated Sliding Tribology of AMMC–Steel Contacts

The present study is focused on the performance evaluation of MoS2, H3BO3, and multiwall carbon nanotubes (MWCNT) used as the potential oil additives in base oil for aluminum metal matrix composites (AMMC)–steel (EN31) tribocontact. Al–B4C composite is used for this purpose; based on a set of preliminary investigation under unlubricated and fresh oil lubrication, three different types of AMMCs (Al–SiC, Al–B4C, and Al–SiC–B4C) were used. A pin-on-disk tribometer is used for all the friction and wear tests under operating condition of load 9.8 N and sliding velocity of 0.5 m/s. From the particle-based wet tribology, it is clear that both the additives H3BO3 and MWCNT improve the friction as well as wear behavior for selected composite contacts. Multiwall carbon nanotubes emerged out as superior among all the additives, whereas MoS2 additives show marginal enhancement in frictional performance under given operating conditions. Fractography and morphological study of pin specimens are carried out to identify the underlying friction and wear mechanisms.

Effect of MoS2 on the tribological properties of carbon fabric composites under wet conditions

Carbon fabric reinforced phenolic composites are very attractive for use as friction materials under wet conditions due to their excellent self-lubricity, wear resistance, and high mechanical strength. However, brittle fracture of carbon fabric bundles during friction is one of the major problems that limit their application. In this work, MoS2 particles were used as additives and friction modifiers to improve the wear and friction behaviors. The composites containing different amounts of MoS2 particulates (0–20 wt%) were fabricated by impregnation technique. The influence of MoS2 on the tribological properties under oil-lubricated conditions has been studied systematically. The experimental results revealed that tribological characteristics such as coefficient of friction and wear resistance were changed significantly with the relative amount of MoS2. Addition of MoS2 within 15 wt% was found to decrease the wear rates of the composites, while 20 wt% MoS2-filled composites exhibited highest wear rate compared to other test samples. Increasing MoS2 content resulted in a rise in the wear rate of the counterparts. Wear mechanisms had been investigated by scanning electron microscope, which could support the observed wear performance.

Influence of MoS2 on the Rolling Contact Performance of Bearing Steels in Boundary Lubrication: A Different Approach

Effective lubrication has been achieved under vacuum conditions by employing MoS2 as a solid lubricant. The primary reason for its ability to reduce friction is attributed to its crystal structure, which allows easy shearing of MoS2 layers. This research explores the possibilities of utilizing MoS2 in soluble and insoluble forms to improve the performance of tribological systems. In this study, spherical rolling elements were coated with Ti–MoS2 and their tribological performance was evaluated in a ball-on-rod tribometer operating in boundary-lubricated (PAO ISO 10 oil) conditions. The results of these tests were compared with similar tests performed on uncoated steel specimens using PAO ISO 10 oil with and without a molybdenum dialkyldithiocarbamate (MoDTC) additive. The L50 fatigue lives of M50 rods tested against Ti–MoS2 coated balls were found to be similar to those obtained from tests performed on uncoated steel specimens using oil with MoDTC (1 wt%); that is, the L50 fatigue lives of M50 rods were improved by more than a factor of 2 in both cases. Tribofilms generated on M50 rods during testing with Ti–MoS2 coated balls in neat oil and uncoated balls in MoDTC (1 wt%) mixed oil were observed to be similar. Wear track analysis on M50 rods tested against Ti–MoS2 coated balls indicated that the tribofilms are mixtures of MoS2 and amorphous hydrocarbon (a-C:H). A possible mechanism for the formation of the a-C:H on the counterface is proposed based on the experimental investigations in this study. Further, it is concluded that the Ti–MoS2 coating on the spherical rolling elements functions as an MoS2 additive source to the lubricating oil rather than as a tribological coating.

Cold-Sprayed Cu-MoS2 and Its Fretting Wear Behavior

Cu and Cu-MoS2 coatings were fabricated by cold spray, and the fretting wear performance of the two coatings was compared. A mixture (95 wt.% Cu + 5 wt.% MoS2) was used as feedstock for the composite coating. Coatings were sprayed with identical gas flow conditions on the substrates pre-heated to approximately 170 °C. The morphology of coating top surface and polished cross sections was analyzed by scanning electron microscopy (SEM) and light optical microscopy (LOM). The influence of MoS2 on Cu deposition was examined. The local MoS2 concentration within the coating was found to affect the hardness. Fretting tests were carried out at two different normal loads, and the influence of MoS2 on friction and wear was studied. The morphology and elemental compositions of the wear scars and wear debris were observed by SEM and energy dispersive x-ray spectroscopy (EDS), respectively.

Influence of MoS<sub>2</sub> on Microstructure and Mechanical Behaviours of Al6061-Al<sub>2</sub>O<sub>3 </sub>Hybrid Composite

In this investigation, the influence of MoS2 on the mechanical properties of Al6061-Al2O3hybrid composites was studied. The composites of Al6061 alloy, AA 6061-6% Al2O3 and Al6061-6% Al2O3-2% MoS2 were manufactured using Stir casting method. These samples were examinedusing optical microscope for the dispersion of reinforcement (Al2O3 ) and solid lubricant (MoS2).The micro structure revealed that there were even distribution of the additives in the Al6061 matrix.The presence of these particles improved the mechanical properties of the composites. For these compositions flexural strength was found using 3 point bending test and impact strength was found using Charpy test. It was observed that the hardness, toughness and flexural strength values increases with the addition of Al2O3 and decreases with the addition of MoS2 to the second composition.

Sliding Wear Behavior of Cast Iron: Influence of MoS2 and Graphite Addition to the Oil Lubricant

The present study discusses sliding wear characteristics of a gray cast iron over a range of applied loads in oil lubricated condition. Effects of MoS2 and graphite addition to the oil lubricant in governing the wear behavior have also been studied. The wear rate increased with load in general with a few exceptions in the case of oil plus 5% MoS2 wherein it had a tendency to show a reverse trend in the intermediate load range. Addition of 5% graphite to the oil brought about a decrease in the wear rate without affecting seizure resistance. Increasing quantity of graphite in the oil from 5 to 10% practically did not affect the wear rate at lower loads. However, it led to significantly lower wear rates at higher loads and also offered higher seizure resistance. In the case of oil plus 5% MoS2 lubricant mixture, the wear rate of the samples was higher than that of the lubricant with 5% graphite when tests were conducted at lower loads while identical response was observed at higher loads in both cases. Seizure resistance of the samples was not affected by the addition of 5% graphite and MoS2 to the oil. The frictional heating also increased with load in general, except in the case of oil containing 5% MoS2 and 10% graphite wherein it remained practically unaffected in the intermediate load range. The presence of 5% graphite and MoS2 in the oil lubricant brought about reduced frictional heating, except in the case of oil plus 5% graphite mixture wherein the trend reversed, and oil plus 5% MoS2 leading to comparable frictional heating during specimen seizure. Increasing test duration caused higher frictional heating. Adhesion was observed to be the principal wear mechanism while microcracking assisted delamination and abrasion also contributed to material loss.

The influence of MoS2 on tribology characteristic parameter of Ni60A/MoS2 composite lubricating coating

The influence of MoS2 on the tribology characteristic parameter of Ni60A/MoS2 composite lubricating coating was researched on the UMT-2 fretting abrasion tester (USA). The result shows that with increasing content of MoS2, the hardness curve of the composite coating decreases and the trend accelerates. Under the same experimental conditions, the mass loss of plasma spray composite coating without adding MoS2 is 1.27×10−2 mg. When the amount of MoS2 reaches 35%, the mass loss is 0.96×10−2 mg. It can be seen that adding MoS2 phase can improve the wear resistance, the amplitude of which is close to 30%. The friction coefficient of plasma spray composite coating without adding MoS2 is 0.23. Adding MoS2 could decrease the friction coefficient of the coating and presents a downtrend. When the mass fraction is 35%, the friction coefficient is the smallest (0.13), and the range is doubled.

Synthesis and magnetic properties of ferrite-metal composite powders : N.Hiratsuka et al (Saitama University, Urawa, Japan) J.Japan Soc. Powder and Powder Metallurgy, vol 40, no 10, 1993, 998–1001. (In Japanese)

Molybdenum disulphide (MoS2) is a well-known and widely used solid lubricant. As such, it might also be a useful addition in the production of composite self-lubricating high-speed steel parts which are used in different anti-wear applications. MoS2 might also have a favourable influence on the synthesis of sintered HSS. In view of this, the compressibility and the sinterability of M3/2 and M35 types of HSS powder mixtures with MoS2 additions were investigated. In this paper, the influence of MoS2 on the densification during vacuum sintering of selected HSSs is presented. It has been established that the densification of HSS-MoS2 powder mixture proceeds by a combination of a reactive and super-solidus liquid-phase sintering process. The added MoS2 reacts with the steel matrix, enhancing densification. Complex sulphides (Cr, V, Fe)S are formed, whilst the Mo enriches the steel matrix and forms complex carbides with other alloying elements.

Influence of MoS2, graphite, and sul'fol on antiwear and extreme-pressure properties of polytetrafluoroethylene greases (PTFE greases)

Influence of MoS2, graphite, and sul'fol on antiwear and extreme-pressure properties of polytetrafluoroethylene greases (PTFE greases)