Subjects -> PHYSICS (Total: 857 journals)
    - ELECTRICITY AND MAGNETISM (10 journals)
    - MECHANICS (22 journals)
    - NUCLEAR PHYSICS (53 journals)
    - OPTICS (92 journals)
    - PHYSICS (625 journals)
    - SOUND (25 journals)
    - THERMODYNAMICS (30 journals)

PHYSICS (625 journals)            First | 1 2 3 4     

Showing 601 - 741 of 741 Journals sorted alphabetically
Tectonics     Full-text available via subscription   (Followers: 15)
The European Physical Journal H     Hybrid Journal   (Followers: 2)
The European Physical Journal Plus     Open Access   (Followers: 1)
The Physics Teacher     Full-text available via subscription   (Followers: 361)
Theoretical and Computational Fluid Dynamics     Hybrid Journal   (Followers: 22)
Theoretical and Mathematical Physics     Hybrid Journal   (Followers: 8)
Thermal Science and Engineering Progress     Open Access   (Followers: 6)
Transport Phenomena in Nano and Micro Scales     Open Access  
Tribologie und Schmierungstechnik     Full-text available via subscription  
Tribology International     Hybrid Journal   (Followers: 47)
Tribology Letters     Hybrid Journal   (Followers: 9)
Turkish Journal of Physics     Open Access  
Ultrasonics     Hybrid Journal   (Followers: 9)
Ultrasonics Sonochemistry     Hybrid Journal   (Followers: 2)
Ultrasound in Medicine & Biology     Hybrid Journal   (Followers: 10)
Universal Journal of Physics and Application     Open Access  
Unnes Physics Education Journal     Open Access   (Followers: 1)
Vibration     Open Access   (Followers: 30)
Virtual Journal of Quantum Information     Hybrid Journal   (Followers: 3)
Water Waves     Hybrid Journal  
Western Journal of Communication     Hybrid Journal   (Followers: 5)
Women & Performance: a journal of feminist theory     Hybrid Journal   (Followers: 15)
World Journal of Condensed Matter Physics     Open Access   (Followers: 2)
Zeitschrift für angewandte Mathematik und Physik     Hybrid Journal   (Followers: 2)
Фізика і хімія твердого тіла     Open Access  

  First | 1 2 3 4     

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Tribology Letters
Journal Prestige (SJR): 1.204
Citation Impact (citeScore): 2
Number of Followers: 9  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1573-2711 - ISSN (Online) 1023-8883
Published by Springer-Verlag Homepage  [2468 journals]
  • Correction to: Molecular Dynamics Modeling of Thermal Conductivity of
           Several Hydrocarbon Base Oils

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      PubDate: 2024-02-22
       
  • Preparation of Liquid Metal-based SiC/Graphene Binary Hybrid Nanofluid and
           Its Basic Properties as Hydraulic Transmission Medium

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      Abstract: Liquid metal (LM) with good room-temperature fluidity and high-temperature stability is an ideal base fluid for extreme high-temperature hydraulic transmission medium. However, the low viscosity and high density of LMs are not conducive to the sealing and lubrication performance of hydraulic components. Using Ga68.5In21.5Sn10 as the base fluid and SiC nanoparticles and graphene with good self-lubricity as a dispersed phase through homogenization and grinding, the novel LM-based SiC/Graphene binary hybrid nanofluid were prepared. The basic physical properties, rheological properties and lubricity at 25–200 °C of LM-based SiC/Graphene binary hybrid nanofluid at 0% 5 vol. %, 10 vol. %, 20 vol. % and 30 vol. % of nanoadditives were also explored. Compared with existing high-temperature hydraulic medium, LM-based SiC/Graphene binary hybrid nanofluid has excellent thermal stability, excellent heat dissipation performance, smaller temperature-viscosity changes, and good high-temperature lubricating performance. We selected 20 vol. % of the samples with the most suitable rheological and lubricating properties for hydraulic transmission medium and evaluated the volumetric efficiency and wear of the gear pump by introducing the samples into a hydraulic system. The results show that compared to pure LM, 20 vol. % of the sample can improve the volumetric efficiency of the gear pump and demonstrate good anti-wear performance. Graphical
      PubDate: 2024-02-15
       
  • Clarification of the Effect of Surface Energy on Tribological Behavior of
           Two-Phase Lubricant Using Reflectance Spectroscopy and Hydrodynamic
           Analysis

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      Abstract: Abstract Recently, a new type of lubricant called two-phase lubricants has been developed to realize a high viscosity index. Two-phase lubricants are mixtures of two different lubricants, realizing low viscosity even at low temperatures due to the temperature dependence of the solubility of the lubricant molecules. In the present paper, the effect of surface energy on the tribological behavior of the two-phase lubricant is clarified using in situ observation with reflection spectroscopy. Sliding surfaces with high hydrogen-bonding terms in the surface energy components attracted high-polar lubricants, resulting in reduced friction. Analysis of the theoretical friction coefficient using Couette flow assumption revealed an important design concept of two-phase lubricants: the concentration of high viscosity lubricants on solid surfaces develops a viscosity distribution in the oil film, resulting in reduced friction.
      PubDate: 2024-02-13
       
  • 3D Printing Composite with Microcapsules for On-Demand Lubrication

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      Abstract: Abstract The lubricating material near the friction area plays a crucial role for many friction components. In this study, utilizing the advantages of 3D printing layer-by-layer accumulation, a lubricating layer containing microcapsules was constructed on the surface of the matrix to achieve active lubrication on-demand. It was found that using on-demand lubrication printing scheme allowed equal amounts of microcapsules to provide superior lubrication compared to integral lubrication. The coefficient of friction (COF) of the composites with on-demand lubrication was reduced to 0.08, with a decrease of 89.6%, compared to the uniform distribution of the conventional lubricant, with no significant reduction in the compressive strength and a reduction in the wear rate by two orders of magnitude; The on-demand lubricated composite has a friction coefficient as low as 0.057 and a compressive strength of about 160 MPa when destroyed. It was demonstrated that the part containing microcapsules on the surface acted as a lubricant, and the part without microcapsules acted as load-bearing. Therefore, the composite material had good mechanical properties and excellent self-lubricating ability. This study pioneered the application of microcapsules in light-curing 3D printing, compared the effects of various printing schemes and different additions of microcapsules added into the photosensitive resins, and provided ideas for the preparation of friction parts with better overall performance.
      PubDate: 2024-02-09
       
  • The Effect of Carbon Structure of DLC Coatings on Friction Characteristics
           of MoDTC-Derived Tribofilm by Using an In Situ Reflectance Spectroscopy

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      Abstract: In this study, six types of DLC coatings were prepared, featuring different carbon structures (including amorphous ta-C coatings and GNC coatings with nanocrystallites) and different doped Ta amounts, to investigate friction characteristics. The results of friction tests with MoDTC-added lubricant revealed a consistent trend: DLC coatings with a higher ID/IG ratio exhibited lower friction coefficients. In addition, in situ observations using reflectance spectroscopy highlighted that the tribofilm formed on DLC coatings with a higher ID/IG ratio maintained a higher \({{\text{MoS}}}_{2}/({{\text{MoS}}}_{2}+{{\text{MoO}}}_{3})\) ratio, which exhibited a strong correlation with the friction coefficient. Measurements of a work function of each DLC coating indicated that those with a higher ID/IG ratio had a higher work function, suggesting the inclusion of a larger amount of graphite structure defects. These active defects in the graphite structure were deemed responsible for enhancing the friction reduction effect of MoDTC. The outcomes of this study propose a material design approach for DLC coatings that amplifies the effectiveness of lubricant additives in friction reduction. Graphical abstract
      PubDate: 2024-02-09
       
  • Effect of Electrical Current on the Tribological Property of Cu-Graphite
           Brush

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      Abstract: Electrical brushes are essential parts of electrical circuits that can transmit electric power and signal between the moving and stationary parts by sliding, so they are exposed to both mechanical and electrical loading. In this study Cu-graphite brush was prepared by the powder metallurgy process, and was tested in rotating sliding electrical contact under different currents. The effect of electrical current on the tribological property of the Cu-graphite brush was investigated by evaluating the friction, wear, contact resistance and temperature. Results illustrate that the static contact resistance of Cu-graphite brush decreases sharply with an increase in the contact force. The friction coefficient and sliding contact resistance decrease gradually with increasing current, which is because of the Joule heat resulting in the reduction of the shear strength and the increase of real contact area. The formation of a continuous transfer layer on steel disc also contributes to the decrease of contact resistance. Oxidation of the wear debris and formation of hard particles causes abrasive wear. The dominant wear mechanism of the Cu-graphite brush with current is electrical wear. Graphical
      PubDate: 2024-01-28
       
  • Wear Performance of Electro-Fluid Mask In Situ Forming TiO2-MoS2 Alternate
           Coatings Under Different Friction Conditions

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      Abstract: In this paper, the electro-fluid mask in situ forming technique was used to prepare a horizontally alternating TiO2-MoS2 lubricant-hard composite coating on the surface of a titanium alloy substrate, which can play the role of both lubricant and hard coatings at the same time. The micromorphology, mechanical properties, and tribological behaviors of the alternate coating were studied. Compared with pure MoS2 coatings and TiO2-MoS2-laminated coatings, the alternate sample JT had the lowest friction coefficient of ~ 0.063. By changing the friction conditions, it was found that the friction coefficient of TiO2-MoS2 lubricant-hard alternate coating decreased with increasing external load within the range of 2–8 N force, and in the range of 3–11 mm/s friction velocity, the friction coefficient decreased first and then increased with increasing sliding velocity. However, the alternate coating had a worse anti-friction effect in the high-temperature air environment. And the anti-friction mechanism of the TiO2-MoS2 alternate coating under different friction conditions was analyzed. Graphical
      PubDate: 2024-01-27
       
  • Friction Properties and Mechanism of Aluminum Sheets Under an Eco-Friendly
           CMCS Lubrication Condition

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      Abstract: The eco-friendly tendency in the aluminum (Al) chemical mechanical polishing (CMP) process urgently requires a nontoxic, biodegradable, and cost-effective lubricant. To solve this challenge, Carboxymethyl chitosan (CMCS) lubricant was introduced into the polishing slurry. The wear mechanism of the Al sheet under dry friction, water lubrication, and CMCS lubrication conditions were investigated. The friction experiments were conducted with a Si3N4 ball sliding on the surface of the Al sheet under three different conditions. Adhesive wear was found to be prominent under dry friction and water lubrication conditions. Moreover, materials spalling leads to wear under CMCS lubrication condition. More specifically, a molecule-scale material removal mechanism was confirmed under the condition of a minimum wear depth of 0.315 nm per single scratch and a corresponding minimum wear rate of 0.1702 × 10−6 mm3/s, when CMCS lubrication was applied. Consequently, when CMCS lubrication at the pressure of 1.0 psi was exploited, the surface roughness (Ra) of the Al sheet after CMP was observed to be 0.22 nm, and such a result further implied that an Al-CMP induced, eco-friendly CMCS solution at low pressure contributes to the low-damaged planarization. Graphical
      PubDate: 2024-01-27
       
  • Molecular Dynamics Study of Nano-Grinding Behavior for Silicon Wafer
           Workpieces with Nanoscale Roughness Under Diamond Abrasive Rotation and
           Translation

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      Abstract: Abstract This study aims to analyze the nano-grinding behavior of silicon wafer workpieces with nanoscale roughness by molecular dynamics simulations. The nano-grinding process of silicon wafer workpieces with varying root-mean-square roughness under different grinding depths is simulated, considering synchronous rotation and translation of the diamond abrasive. The material removal mechanism, thermodynamic properties and mechanical responses are revealed. The findings demonstrate that the material removal in the nano-grinding process can be influenced by surface roughness and grinding depth, leading to its classification into compression, ploughing and cutting regimes. Moreover, reducing the grinding depth and surface roughness also reduces temperature, von Mises stress and grinding force, thus mitigating surface damage to silicon wafer workpieces. However, a minimal initial root-mean-square roughness may result in reduced surface smoothness of silicon wafer workpieces after a single grinding.
      PubDate: 2024-01-25
       
  • Contact Stiffness and Damping in Atomic-Scale Friction: An Approximate
           Estimation from Molecular Dynamics Simulations

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      Abstract: Abstract The stick–slip friction observed in an atomic force microscope (AFM) experiment has been widely studied using the Prandtl-Tomlinson (PT) model or molecular dynamics (MD) simulations. However, the mechanisms of friction energy dissipation in AFM are still not well understood. Our detailed MD simulations of a benchmark system, a Pt metal tip sliding on the Au (111) surface, provide a method of computing the contact stiffness and damping between the tip apex and the metal surface. We revealed that the contact stiffness is largely dependent on the very first contact layer atoms of the tip apex, but essentially independent of the temperature and the atomic mass of the AFM tip, and is also less dependent on the normal load if the contact geometry remains unchanged in elastic contact. Furthermore, by connecting the atomic relaxation rate to the damping coefficient, an important parameter gauging the friction dissipation in the PT model but the choice of which is usually empirical, we demonstrate that this damping coefficient is dependent on the atomic structure of the tip apex and the intrinsic relaxation rate of the individual atoms in the contact layer. We use such mechanisms to calculate the two parameters and carry out Langevin dynamics simulation within the framework of the PT model for two friction systems: a small Pt tip consisting of 3956 Pt atoms and a large polycrystalline Pt tip consisting of 18,365 Pt atoms. Our simulation results show that both tip apexes are underdamped in a stick–slip friction. We also demonstrate that the results from the Langevin dynamics simulation using these two critical parameters compared remarkably well with the straightforward MD simulation results in a range of sliding velocity (V = 0.01 – 1 m/s).
      PubDate: 2024-01-17
       
  • Control of Static Friction by Designing Grooves on Friction Surface

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      Abstract: This study numerically investigated the friction of viscoelastic objects with grooves. A 3D viscoelastic block with grooves on a rigid substrate is slowly pushed from the lateral side under uniform pressure on the top surface. The local friction force at the interface between the block and the substrate obeys Amontons’ law. Numerical results obtained using the finite element method reveal that the static friction coefficient decreases with increasing groove width and depth. The propagation of the precursor slip is observed before bulk sliding. Furthermore, bulk sliding occurs when the area of slow precursor slip reaches a critical value, which decreases with increasing groove size. A theoretical analysis based on a simplified model reveals that the static friction coefficient is related to the critical area of the precursor, which is determined by the instability of the precursor. A scaling law for the critical area is theoretically predicted, and it indicates that the decrease in the effective viscosity due to the formation of the grooves leads to a decrease in the static friction coefficient. The validity of the theoretical prediction is numerically confirmed. Graphical
      PubDate: 2024-01-17
       
  • Elastic Shakedown and Roughness Evolution in Repeated
           Elastic–Plastic Contact

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      Abstract: Surface roughness emerges naturally during mechanical removal of material, fracture, chemical deposition, plastic deformation, indentation, and other processes. Here, we use continuum simulations to show how roughness which is neither Gaussian nor self-affine emerges from repeated elastic–plastic contact of rough and rigid surfaces on a flat elastic–plastic substrate. Roughness profiles change with each contact cycle, but appear to approach a steady-state long before the substrate stops deforming plastically and has hence “shaken-down” elastically. We propose a simple dynamic collapse for the emerging power-spectral density, which shows that the multi-scale nature of the roughness is encoded in the first few indentations. In contrast to macroscopic roughness parameters, roughness at small scales and the skewness of the height distribution of the resulting roughness do not show a steady-state. However, the skewness vanishes asymptotically with contact cycle. Graphical
      PubDate: 2024-01-17
       
  • Modeling and Experimental Validation of Anchoring Resistance of the Radial
           Expanding Capsule Robot in the Intestine

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      Abstract: The anchoring performance of the radial expanding capsule robot (RECR) in the intestine is crucial to the accuracy of the examination. However, there is a lack of relevant research at present. In this article, the anchoring resistance model of the radial expanding capsule robot (RECR) in the intestine is established by the theoretical analysis and verified by the experiment. Based on the anchoring resistance model, the optimization method to improve the anchoring performance of the RECR is proposed. Firstly, the biomechanical properties of the intestine in the expanding state are studied, and the longitudinal contour equation of the intestine is obtained. The anchoring resistance model of the RECR in the intestine is established by analyzing the mechanical characteristics between the capsule robot and the intestine. Then, an experimental platform is built, and the anchoring resistance of the testing dummy imitating the RECR with different radii and lengths in the intestine is tested by the platform. The experimental results verify the correctness of the anchoring resistance model. Finally, the expanding force model of a developed inchworm-like RECR is established by the kinematics and mechanical analysis. And combined with the anchoring resistance model, the anchoring performance of the inchworm-like RECR in the intestine is analyzed. The influence of the RECR design parameters on anchoring resistance is quantitatively analyzed, which provides the theoretical basis for the design and optimization of the RECR. Graphical
      PubDate: 2024-01-16
       
  • Effect of Viscous Intermediate Layer on Uneven Wear of Locally Hardened
           Steel

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      Abstract: Local laser hardening of metals and alloys is often used to obtain stable surface texture due to uneven wear. This texture keeps the lubricant on the surface. In this regard, the question arises of the influence of the properties of the lubricant, in particular, its viscosity, on the steady-state geometry of the locally hardened surface. This paper presents the results of experimental study of wear forming of locally hardened steel 100Cr6 in contact with rubber. Two lubricants were used, very different in their viscosity, saturated with abrasive particles. It is obtained that the waviness of the worn surface is asymmetric and depends on sliding direction. The effect is more noticeable for the case of wear with more viscous lubricant. In contact, especially in the presence of wear or abrasive particles, the lubricant often behaves like a viscoelastic layer, the properties of which are determined by the contact conditions and the lubricant characteristics. A new analytical model is developed to study wear of the locally hardened body in which zones have different wear resistance coefficients. In the steel-rubber contact, steel is assumed a rigid body that wears, and rubber is assumed an elastic one. Standard viscoelastic body models the intermediate layer. The steady geometry of the worn surface is presented as analytical dependence on the input parameters. The effect of viscosity in theoretical and experimental results qualitatively coincides. The influence of sliding velocity on the amplitude of the surface waviness was also analyzed; the effect of the intermediate layer is greater for low velocity. Graphical abstract
      PubDate: 2024-01-16
       
  • Scalable Generation of Hybrid Graphene Nanoscrolls for High-Performance
           Solid Lubricants

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      Abstract: Graphene and other 2D materials have been extensively studied as solid lubricants in recent years. Low friction can sometimes be observed in those 2D lubricants, and one possible mechanism is that scroll-shaped nanostructures are formed during friction, which decreases the contact area and energy barrier, thus substantially reducing friction. The integration of graphene with metal or metal oxide nanostructures can further enhance its lubrication properties by increasing film formation ability and easy shearing of the nanosheets. However, it is not possible to reliably promote the formation of such nanoscroll-shaped low friction wear products, which limits the reproducibility and application of such nanostructures as solid lubricants. In this study, we address this issue by creating a scalable method for the synthesis of hybrid graphene-titanium oxide (G–TiO2) nanoscrolls and demonstrating their potential as solid lubricants with macroscopic coefficient of friction as low as 0.02 in ambient conditions. Our approach to generate the nanoscrolls is based on the in situ sol–gel synthesis of TiO2 on graphene followed by spray-freeze-drying–induced shape transformation. The solid lubrication performance of such G–TiO2 nanoscrolls can be further enhanced by applying a thin graphene oxide primer layer, which provides high affinity to both the substrate and the active materials. These hybrid nanoscrolls hold promising potential for applications in aerospace, automotive, and precision manufacturing fields as effective solid lubricants. Graphical
      PubDate: 2024-01-10
       
  • Comparing the Tribological Performance of Water-Based and Oil-Based
           Drilling Fluids in Diamond–Rock Contacts

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      Abstract: Oil-based drilling fluids are usually assumed to provide lower friction compared to their water-based alternatives. However, clear evidence for this has only been presented for steel–rock and steel–steel contacts, which are representative of the interface between the drillstring and the borehole or casing. Another crucial interface that needs to be lubricated during drilling is that between the cutter (usually diamond) and the rock. Here, we present pin-on-disc tribometer experiments that show higher boundary friction for n-hexadecane-lubricated diamond–granite contacts than air- and water-lubricated contacts. Using nonequilibrium molecular dynamics simulations of a single-crystal diamond tip sliding on α-quartz, we show the same trend as in the experiments of increasing friction in the order: water < air < n-hexadecane. Analysis of the simulation results suggests that the friction differences between these systems are due to two factors: (i) the indentation depth of the diamond tip into the α-quartz substrate and (ii) the amount of interfacial bonding. The n-hexadecane system had the highest indentation depth, followed by air, and finally water. This suggests that n-hexadecane molecules reduce the hardness of α-quartz surfaces compared to water. The amount of interfacial bonding between the tip and the substrate is greatest for the n-hexadecane system, followed by air and water. This is because water molecules passivate terminate potential reactive sites for interfacial bonds on α-quartz by forming surface hydroxyl groups. The rate of interfacial bond formation increases exponentially with normal stress for all the systems. For each system, the mean friction force increases linearly with the mean number of interfacial bonds formed. Our results suggest that the expected tribological benefits of oil-based drilling fluids are not necessarily realised for cutter–rock interfaces. Further experimental studies should be conducted with fully formulated drilling fluids to assess their tribological performance on a range of rock types. Graphical
      PubDate: 2024-01-09
       
  • Adhesion and Damage Behaviour of Wheel–Rail Rolling–Sliding Contact
           Suffering Intermittent Airflow with Different Humidities and Ambient
           Temperatures

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      Abstract: The adhesion and damage behaviour of wheel–rail systems play an important role in the safety of railway operations. To verify the low adhesion behaviour of wheel and rail contact during the train entering tunnels in alpine regions caused by intermittent humid and warm airflow, tribology testing using a rolling–sliding contact in the laboratory was conducted to investigate the effect of humid and warm airflow with various ambient temperatures (− 55 to 60 °C) and airflow with different humidities (relative humidity from 5 to 99%) on the instantaneous low adhesion and damage failure between the wheel–rail interface. Results indicate that the instantaneous low adhesion phenomenon and multifarious damage are affected by the humidity of the airflow and the ambient temperature. In the temperature range of − 55 to − 20 °C, the wheel–rail interface will be in a low adhesion state once it encounters a humid and warm airflow attack. As a result, the adhesion coefficient curve exhibits a ‘comb-shaped’ feature. In this temperature range, the wear surface is rougher under the action of high moisture flow, and the main damage mechanism is fatigue wear. In particular, the moisture in the airflow will liquefy into water or even condense directly into frost and ice film on the wheel when the humid and warm airflow encounters the cold wheel surface. Consequently, the adhesion coefficient exhibits a ‘comb-shaped’ feature. In the meantime, the tribological oxidation reaction is more active at humid airflow conditions of 40–60 °C. The high humidity environment is conducive to the formation of water paste during friction, that is, a mixture of oxidized debris and water molecules that acts as friction-reducing layers, which also reduces the adhesion coefficient. These results will help deeply understand that, the wheel–rail adhesion coefficient drops sharply in an instant once the wheel–rail interface encounters the humid and warm airflow in the tunnel. Thus, railway operations department have to be very cognizant of the low adhesion problem, and take effective measures to improve the adhesion of wheel-rail interface to avoid the occurrence this kind of problem. Graphical
      PubDate: 2024-01-08
       
  • In situ Observation of the Formation of MoDTC-Derived Tribofilm on a
           Bearing Steel with Different Surface Roughness by Using a Reflectance
           Spectroscopy and Its Effects on Friction

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      Abstract: In this paper, we evaluated the formation of MoDTC-derived tribofilm and its effects on friction reduction. We conducted in situ observation using reflectance spectroscopy to monitor the tribofilm's evolution during friction, allowing us to estimate its thickness and composition. The results revealed that the rough specimen ( \({R}_{\text{a}}=12.7\) nm) maintained a smaller friction coefficient and a larger volume fraction of MoS2 compared to the smooth specimen ( \({R}_{\text{a}}=2.6\) nm). Additionally, using the in situ observed composition and contact state, we inferred changes in the frictional properties of the tribofilm formed on both specimens. This analysis suggested that the pronounced direct contact of asperities, especially evident in the rough specimen, promoted the formation of a low-friction tribofilm (primarily MoS2), enabling the rough specimen to sustain lower friction. Graphical abstract
      PubDate: 2023-12-21
       
  • On the Shear-Thinning of Alkanes

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      Abstract: Abstract The approximate power law dependence of the apparent viscosity of liquids on shear rate is often argued to arise from a distribution of energy barriers. However, recent work on the Prandtl model, which consists of a point mass being dragged by a damped, harmonic spring past a sinusoidal potential, revealed a similar dependence of the friction on velocity as that of many liquids. Here, we demonstrate that this correlation is not only qualitative but can also be made quantitative over a broad temperature range using merely three dimensionless parameters, at least for alkanes, in particular n-hexadecane, at elevated pressure p. These and other observations made on our all-atom alkane simulations at elevated pressure point to the existence of an elementary instability causing shear-thinning. In addition, the equilibrium viscosity shows power law dependence on p near the cavitation pressure but an exponential dependence at large p, while the additional parameter(s) in the Carreau–Yasuda equation compared to other rheological models turn out justifiable.
      PubDate: 2023-12-20
       
  • Influence of a Succinimide Dispersant on the Tribological Performance of
           MoS2 Nanoparticles

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      Abstract: Abstract In this study, the effect of a polyisobutenyl succinimide (PIB) dispersant on the tribological performances of MoS2 nanoparticles used as lubricant additives in a PAO base oil was investigated. Friction tests were conducted in boundary lubrication regime, in a steel/steel sliding contact configuration, at room temperature and at 100 °C. The tribofilms formed on the rubbed surfaces were analyzed using X-ray Photoelectron Spectroscopy (XPS) and Transmission Electron Microscopy (TEM). The results show that the dispersant used in this work prevented the agglomeration/sedimentation of the nanoparticles and strongly improved their dispersion in the base oil. Its effect on the tribological performance of the nanoparticles was found to be temperature dependent. The best friction-reducing properties were obtained at elevated temperature. It was also found that the dispersant strongly affected the tribofilm’s properties (chemical composition, thickness, MoS2 flake length) and that the best reducing friction properties were obtained when the tribofilm was composed of long and well-dispersed MoS2 flakes aligned in the sliding directions.
      PubDate: 2023-12-15
       
 
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  Subjects -> PHYSICS (Total: 857 journals)
    - ELECTRICITY AND MAGNETISM (10 journals)
    - MECHANICS (22 journals)
    - NUCLEAR PHYSICS (53 journals)
    - OPTICS (92 journals)
    - PHYSICS (625 journals)
    - SOUND (25 journals)
    - THERMODYNAMICS (30 journals)

PHYSICS (625 journals)            First | 1 2 3 4     

Showing 601 - 741 of 741 Journals sorted alphabetically
Tectonics     Full-text available via subscription   (Followers: 15)
The European Physical Journal H     Hybrid Journal   (Followers: 2)
The European Physical Journal Plus     Open Access   (Followers: 1)
The Physics Teacher     Full-text available via subscription   (Followers: 361)
Theoretical and Computational Fluid Dynamics     Hybrid Journal   (Followers: 22)
Theoretical and Mathematical Physics     Hybrid Journal   (Followers: 8)
Thermal Science and Engineering Progress     Open Access   (Followers: 6)
Transport Phenomena in Nano and Micro Scales     Open Access  
Tribologie und Schmierungstechnik     Full-text available via subscription  
Tribology International     Hybrid Journal   (Followers: 47)
Tribology Letters     Hybrid Journal   (Followers: 9)
Turkish Journal of Physics     Open Access  
Ultrasonics     Hybrid Journal   (Followers: 9)
Ultrasonics Sonochemistry     Hybrid Journal   (Followers: 2)
Ultrasound in Medicine & Biology     Hybrid Journal   (Followers: 10)
Universal Journal of Physics and Application     Open Access  
Unnes Physics Education Journal     Open Access   (Followers: 1)
Vibration     Open Access   (Followers: 30)
Virtual Journal of Quantum Information     Hybrid Journal   (Followers: 3)
Water Waves     Hybrid Journal  
Western Journal of Communication     Hybrid Journal   (Followers: 5)
Women & Performance: a journal of feminist theory     Hybrid Journal   (Followers: 15)
World Journal of Condensed Matter Physics     Open Access   (Followers: 2)
Zeitschrift für angewandte Mathematik und Physik     Hybrid Journal   (Followers: 2)
Фізика і хімія твердого тіла     Open Access  

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