Frictional Properties of a Nanocomposite Material With a Linear Polyimide Matrix and Tungsten Diselinide Nanoparticle Reinforcement

2019 ◽  
Vol 141 (8) ◽  
Author(s):  
Alexander D. Breki ◽  
Ekaterina S. Vasilyeva ◽  
Oleg V. Tolochko ◽  
Andrey L. Didenko ◽  
Michael Nosonovsky
Keyword(s):  
Gas Phase ◽  
Solid Lubricant ◽  
Nanocomposite Material ◽  
Friction Mechanism ◽  
Tungsten Diselenide ◽  
Frictional Properties ◽  
Molecular Adhesion ◽  
Frictional Performance ◽  
Polyimide Matrix ◽  
Adhesion Friction

Frictional properties of a self-lubricating nanocomposite material with an A–OOO polyimide matrix reinforced by gas-phase synthesized tungsten diselenide (WSe2) nanoparticles are studied with a homemade low sliding speed tribometer. Tungsten diselenide is often used as a solid lubricant due to its layered structure yielding to anisotropy, which enhances lubrication properties. To facilitate molecular adhesion friction mechanism, friction against a very smooth steel surface (a Johansson gauge block) was used. It is shown that the composite material reinforced with WSe2 nanoparticles has enhanced frictional performance including lower friction and adhesion.

scholarly journals Use of Onion-Like Carbon to Reinforce Carbon Composites

2018 ◽  
Vol 20 (3) ◽  
pp. 201
Author(s):  
A. Galiguzov ◽  
A. Malakho ◽  
S. Minchuk ◽  
L. Oktiabrskaia ◽  
V. Lepin
Keyword(s):  
Solid Lubricant ◽  
Carbon Matrix ◽  
Carbon Composite ◽  
Bending Test ◽  
Nanoindentation Test ◽  
Friction Mechanism ◽  
Three Point Bending ◽  
Lubricating Film ◽  
Nanoindentation Testing ◽  
Porosity Analysis

Onion-like carbon reinforced carbon-carbon composite was fabricated, and the influence of onion-like carbon (OLC) on the microstructure and mechanical and friction properties was investigated by porosity analysis, scanning electron microscopy, three-point bending test, nanoindentation test and ring-on-ring friction test. The results show that the sample containing OLC has a higher flexural strength (by 7.3%) and compressive strength (by 29.3%), hardness (by 2.1 times) and apparent density (by 1.1%) and smaller open porosity (7.9% vs 9.8%) and mesopore volume, which is confirmed by porosity analysis and is attributed to improved fiber/ matrix interface performance. The presence of OLC results in higher hardness and elastic modulus of carbon matrix under nanoindentation testing, which leads to modification of friction mechanism and a decrease in the wear rate under friction (by 3.3 times). Besides, OLC particles form self-lubricating film and show a graphitic carbon solid lubricant properties.

scholarly journals Tribological properties of MoS2 coating for ultra-long wear-life and low coefficient of friction combined with additive g-C3N4 in air

Friction ◽  
2020 ◽  
Author(s):  
Yupeng Zhang ◽  
Panpan Li ◽  
Li Ji ◽  
Xiaohong Liu ◽  
Hongqi Wan ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Solid Lubricant ◽  
Sliding Friction ◽  
Friction Mechanism ◽  
X Ray ◽  
Lubricating Film ◽  
Valence States ◽  
Transmission Electron ◽  
Wear Life

Abstract The solid lubricant MoS2 demonstrates excellent lubricating properties, but it spontaneously oxidizes and absorbs moisture in air, and thus results in poor wear resistance and short wear-life. In this study, the additive g-C3N4 (CN) was successfully combined with MoS2 via hydrothermal synthesis as a solid lubricant for the first time. Meanwhile, a low friction coefficient (COF, μ = 0.031) and ultra-long wear-life of CN/MoS2 compared to pure MoS2 in air were demonstrated. The functional groups and good crystallinity of the lubricant material were characterized via Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD). The formed valence states in CN/MoS2 were analyzed via X-ray photoelectron spectroscopy (XPS). The characterized results of the scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) show the morphology and interior crystal phase structure of CN/MoS2. From the cross-section analysis, the presence of iron oxide nanoparticles lubricating film is synergistic with CN/MoS2 film during the friction process, resulting in its ultra-long wear-life. In particular, the friction mechanism of interlayer sliding friction combined with energy storage friction was analyzed and proposed.

Anisotropic Frictional Behavior of Nanotextured Surfaces

2008 ◽  
Author(s):  
H.-S. Zhang ◽  
K. Komvopoulos
Keyword(s):  
Coefficient Of Friction ◽  
Normal Load ◽  
Ion Beam ◽  
Textured Surfaces ◽  
Friction Mechanism ◽  
Atomic Force ◽  
Afm Imaging ◽  
The Coefficient Of Friction ◽  
Tip Radius ◽  
Adhesion Friction

Silicon wafers were exposed to an oblique Ar+ ion beam to create arrays of surface ripples. Atomic force microscope (AFM) imaging revealed that the rippled (textured) surfaces exhibited highly anisotropic morphologies. Nanoscale friction experiments performed with different diamond tips illustrated a dependence of the coefficient of friction on tip radius, normal load, and sliding direction. Changes in the coefficient of friction are interpreted in terms of the applied normal load and varying contributions of the adhesion friction mechanism.

scholarly journals Ultralow Interlayer Friction of Layered Electride Ca2N: A Potential Two-Dimensional Solid Lubricant Material

Materials ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 2462 ◽  
Author(s):  
Jianjun Wang ◽  
Lin Li ◽  
Ziting Shen ◽  
Peng Guo ◽  
Meng Li ◽  
...  
Keyword(s):  
Density Functional ◽  
Solid Lubricant ◽  
Interlayer Space ◽  
Solid Lubricants ◽  
Two Dimensional ◽  
Friction Behavior ◽  
Friction Mechanism ◽  
Functional Theory ◽  
Ultralow Friction ◽  
Conduction Electrons

Dispersion-corrected density functional theory (DFT) calculations reveal that the layered electride of dicalcium nitride (Ca2N) exhibits stronger interlayer binding interactions but lower interlayer friction behavior than that of traditional layered lubricants weakly bonded by van der Waals (vdW) interactions, such as graphite, h-BN, and MoS2. These results are attributed to the two-dimensional (2D) homogeneous conduction electrons distribution in the middle of the interlayer space of Ca2N, which yields a smooth sliding barrier and hence ultralow friction behavior. The interesting results obtained in this study have not only broadened the scope of 2D solid lubricants but also enriched the physical understanding of ultralow friction mechanism for 2D systems.

scholarly journals Interface Frictional Properties of Geogrid-Reinforced Pond Ash

2019 ◽  
Vol 8 (2) ◽  
pp. 1978-1983
Keyword(s):  
Power Plants ◽  
Thermal Power ◽  
Reinforced Soil ◽  
Friction Mechanism ◽  
Pond Ash ◽  
Interface Friction ◽  
Frictional Properties ◽  
Alternative Material ◽  
Backfill Materials ◽  
Stiffness Characteristics

The performance of any reinforced soil (RS) structure mainly depends on the soil-geosynthetic interface friction mechanism. Nowadays, due to the non-availability of conventional backfill materials and unsuitability of locally available soils, the exploration has started to find an alternative material for backfilling. One of such materials is pond ash, generated as a waste by-product from thermal power plants. In this regard, the present work is aimed to find the interfacial frictional characteristics of geogrid reinforced pond ash in terms of coefficient of interface friction (Ci ) and pullout frictional factor (f*) by conducting large direct shear test and pullout tests using two biaxial geogrids (GG1 and GG2) of different stiffnesses. From the experimental results, it was observed that the coefficient of interface friction (Ci ) values were in the range of 0.84 to 0.66 and pullout frictional factor (f*) values were in the range of 0.43 to 0.28 for the applied normal stresses of 50 kPa, 100 kPa and 150 kPa respectively. Further, GG1 shows higher frictional characteristics compared to GG2 because of its structural geometry and stiffness characteristics.

scholarly journals Friction Mechanism Features of the Nickel-Based Composite Antifriction Materials at High Temperatures

Coatings ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 454 ◽  
Author(s):  
Adam Kurzawa ◽  
Tetiana Roik ◽  
Oleg Gavrysh ◽  
Iuliia Vitsiuk ◽  
Miroslaw Bocian ◽  
...  
Keyword(s):  
High Temperatures ◽  
Solid Lubricant ◽  
Atmospheric Oxygen ◽  
Thermodynamic Simulation ◽  
Operating Conditions ◽  
High Wear Resistance ◽  
Friction Behavior ◽  
Friction Mechanism ◽  
Antifriction Properties ◽  
Contact Surfaces

The friction behavior of the formed antifriction films and their effect on the functional properties of the composite based on the powder nickel alloy EI929 with solid lubricant CaF2 at high temperatures was investigated. An antifriction film was formed on the contact surfaces during the friction process. Such a film was the result of the interaction of the contact surfaces with atmospheric oxygen at high temperatures. It contains oxides of alloying elements from materials of the frictional contact and solid lubricant calcium fluoride. The quantitative ratio of formed oxides depends on the temperature operating conditions of material. The data of thermodynamic simulation of the high-temperature interaction of the composite with oxygen coincide with the experimental data obtained by studying the fine structure of surface antifriction films. Antifriction films consist of oxide phases in combination with solid CaF2 lubricant. Anti-friction films provide high wear resistance of the self-lubricating composite in the range of temperatures 1073–1173 K due to the balance between the rate of their formation and wear. When the temperature exceeds 1200 K, the film loses its lubricating properties and acts as an abrasive substance due to the intense oxidation. Abrasive surfaces of materials were subjected also to microscopic examination, in which the mechanically mixed layer (MML) was described. The study of the friction surface roughness parameters confirmed the presence of the formed friction self-lubricating film and allowed to determine its parameters. The friction mechanism was the formation of an oxide layer combined with a solid lubricant, which provides high antifriction properties in the range of 1073–1273 K.

scholarly journals Friction mechanism of polymers and their composites

2018 ◽  
Vol 37 (1) ◽  
pp. 1 ◽  
Author(s):  
Gordana Bogoeva-Gaceva ◽  
Dimko Dimeski ◽  
Vineta Srebrenkoska
Keyword(s):  
High Performance ◽  
Friction And Wear ◽  
Polymer Matrix Composites ◽  
Short Fiber ◽  
Matrix Composites ◽  
Reinforced Composites ◽  
Friction Mechanism ◽  
Thermosetting Polymers ◽  
Tribological Parameters ◽  
Adhesion Friction

This paper provides a brief review of the tribological properties of polymers and polymer matrix composites (PMCs) and the relevant mechanisms of friction and wear. The influence of both molecular and mechanical components on friction involving polymers as well as the influence of fillers, reinforcements and dry lubricants on the overall tribological characteristics of PMCs is evaluated. Tribological parameters include surface roughness, the mechanism of adhesion, friction and wear, and chemical interactions with dry lubricants (if present). The article reviews the main factors that influence the wear and frictional characteristics of thermoplastic and thermosetting polymers, short fiber reinforced composites and high-performance unidirectional composites. Examples of quantitative data of different pairs of polymers and PMCs with the counterface are presented.

scholarly journals Investigation on the Frictional Performance of Surface Textured Ring-Deformed Liner Conjunction in Internal Combustion Engines

Energies ◽  
2019 ◽  
Vol 12 (14) ◽  
pp. 2761 ◽  
Author(s):  
Cheng Liu ◽  
Yanjun Lu ◽  
Yongfang Zhang ◽  
Lujia Tang ◽  
Cheng Guo ◽  
...  
Keyword(s):  
Surface Texture ◽  
Power Dissipation ◽  
Internal Combustion Engines ◽  
Fuel Efficiency ◽  
Internal Combustion ◽  
Combustion Engines ◽  
Frictional Properties ◽  
Frictional Performance ◽  
Lubrication Condition ◽  
Micro Dimples

In internal combustion engines (ICEs), the frictional performance of ring-liner conjunction (RLC) has drawn special attention because it greatly affects the fuel efficiency of the engines. In recent years, surface texture (i.e., micro dimples or grooves) has emerged as a promising approach to improve the frictional performance of RLC. However, most current studies on surface textured RLC were conducted by assuming that the liner was ideally circular and the lubrication condition was either fully flooded or starved. In this study, to evaluate the frictional characteristics of an RLC with surface texture on the ring, a numerical model of lubrication is presented by considering the liner deformation, as well as the coexistence of the fully flooded and staved lubrication conditions in an engine cycle. On this basis, the frictional properties of a surface textured RLC are analyzed, and the impacts of the liner deformation and temperature on the friction-reducing effect of the surface texture are also evaluated. The results show that the surface texture on the ring can effectively reduce the power dissipation and friction dissipation of an RLC, and the reductions vary with the liner temperature and deformation. Large reductions in the power dissipation and friction dissipation of an RLC are obtained when the liner temperature is low or the liner deformation is small.

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