scholarly journals The Effect of Fullerene Soot Nanoparticles on the Microstructure and Properties of Copper-Based Composites

Nanomaterials ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1929
Author(s):  
Elizaveta V. Bobrynina ◽  
Tatiana V. Larionova ◽  
Tatiana S. Koltsova ◽  
Aleksey I. Shamshurin ◽  
Oksana V. Nikiforova ◽  
...  

Copper-based composite materials strengthened with nanosized fullerene soot particles were produced by mechanical milling and hot pressing technology with a content of carbon up to 5 wt. %. The microstructure of the composite powders and the compacts prepared using them were examined by light microscopy, SEM, EDS, XRD, and XPS; hardness, heat conductivity, and tribological characteristics were measured. The interesting feature of the observed microstructure was a “marble” pattern formed by a white boundary net. The study shows homogeneous distribution of carbon inside the copper grains and its lower concentration in the grain boundaries. The effect was caused by a reaction of carbon with oxygen adsorbed by the copper particles surface. The maximal hardness of the material is 160 HB for the sample with 0.5 wt. % of fullerene soot; this material has the minimal friction coefficient (0.12) and wear in a dry friction condition. Heat conductivity of the material (Cu-0.5 wt. % C) is 288 W/m*K.

2012 ◽  
Vol 3 (3) ◽  
pp. 181-190
Author(s):  
G. Fledrich ◽  
R. Keresztes ◽  
L. Zsidai

The zirconium dioxide as basic material is suitable to machine by tool with regular edge derivingfrom lower ceramic hardness and from other characteristics so in case of piece production or small – andmedium series production, at quick prototype production can become potential material alike. The aims tocompare the arising frictional characteristics in case of dry friction condition in case of ceramic – steelsurface pairs machined with different sets. We have developed for an equipment to carry out tribologicaltests. During the test we pressure the steel counter face with determined normal direction force thecasing surface of the rotating ceramic specimen and in the meantime we measure the value of the frictionforce with force meter cell. We have calculated the friction coefficient characterizing the system from thenormal direction force and the friction force as well as we measured the wear of the steel specimen andits deformation.


Author(s):  
LiQin Wang ◽  
JianWei Sun ◽  
Le Gu

The tribological performance of Polyetherimide (PEI) composites filled with different Polytetrafluoroethylene (PTFE) content was comparatively evaluated on MM-200 test rig in block-on-ring configuration under dry friction condition. The microstructures of worn surfaces, fractured surfaces and wear mechanisms of the PEI composite were examined under scanning electron microscope (SEM). The variations of elastic modulus and surface hardness with variation in composition were also investigated. The results showed that under conditions of dry friction the PTFE can lower the friction coefficient and reduce wear of the PEI composites. When filled with 10 wt. % PTFE, the composite had the lowest wear rate. For PEI filled with 5wt. % PTFE the friction coefficient was about 0.3 and remained comparatively stable with increase of the PTFE content.


2018 ◽  
Vol 913 ◽  
pp. 205-211
Author(s):  
Dong Mei Liu ◽  
Qiang Song Wang ◽  
Wei Yuan ◽  
Xu Jun Mi

A comparative study on the friction and wear properties of three kinds of copper alloys, including Cu-Ni based, Cu-Al and Cu-Be alloys was carried out in this study. The friction pair was stainless steel, and both dry and MoS2 lubrication friction experiments were investigated. During the experiments, different loads were chosen for different alloys. It was found that under dry friction condition, the friction coefficients of both Cu-Ni based and Cu-Al alloys did not change as the loads changes, whereas the friction coefficient of Cu-Be alloy increased as the loads increases. Under lubrication friction condition, the friction coefficients of all three alloys did not change as the load changes. The results show that the dry friction coefficient of Cu-Ni based alloy was the largest (0.74), the Cu-Al alloy next (0.60), and the Cu-Be alloy had the smallest dry friction coefficient (0.54). The lubrication friction coefficient of Cu-Ni based and Cu-Be was equal and relatively smaller (0.12), whereas the Cu-Al alloy had a relative larger lubrication friction coefficient (0.27). The microstructure observations were consistent with the friction and wear performance, and the SEM results show that different wear mechanisms were dominated for different alloys.


Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6438
Author(s):  
Firuz Yunusov ◽  
Tatiana V. Larionova ◽  
Oleg Tolochko ◽  
Alexander D. Breki

Aluminum-based composite materials reinforced with fullerene soot, which is a mixture of fullerene and amorphous carbon, are promising materials for friction and wear applications. Composite materials: aluminum with 2% fullerene soot (f.s) and Al with 2% f.s and 2% Cu were obtained via mechanical milling followed by hot pressing. The tribological properties (friction and wear) of the listed composites were investigated and compared with the results for pure aluminum obtained under similar conditions. It has been shown that the addition of fullerene soot reduces the friction coefficient by 25%. At additional alloying with copper, the friction coefficient decreased by 35% in comparison with pure aluminum and also lad to a decrease in friction fluctuations. The wear rate of composite Al with 2% f.s decreased twice in comparison with that of pure aluminum, and with additional alloying it decreased 2.5 times. The morphology of the wear surfaces was investigated by scanning electron microscopy (SEM). The influence of fullerene soot and additional alloying on the wear mechanism was shown.


Author(s):  
И.А. Кобыхно ◽  
Ф.А. Юнусов ◽  
А.Д. Бреки ◽  
О.В. Толочко ◽  
А.Г. Кадомцев

The paper presents the results of tribological studies of carbon fiber reinforced polymer filled with fullerene soot nanoparticles. It is shown that the dry friction coefficient of the materials does not change when the fullerene soot concentration increases up to 4wt%, but an increase in the friction force occurs due to the forces of intermolecular attraction, the resultant of which monotonically increases.


Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 660
Author(s):  
Dariusz Jędrzejczyk ◽  
Elżbieta Szatkowska

The analyzed topic refers to the wear resistance and friction coefficient changes resulting from heat treatment (HT) of a hot-dip zinc coating deposited on steel. The aim of research was to evaluate the coating behavior during dry friction after HT as a result of microstructure changes and increase the coating hardness. The HT parameters should be determined by taking into consideration, on the one hand, coating wear resistance and, on the other hand, its anticorrosion properties. A hot-dip zinc coating was deposited in industrial conditions (according EN ISO 10684) on disc-shaped samples and the chosen bolts. The achieved results were assessed on the basis of tribological tests (T11 pin-on-disc tester, Schatz®Analyse device, Sindelfingen, Germany), microscopic observations (with the use of optical and scanning microscopy), EDS (point and linear) analysis, and microhardness measurements. It is proved that properly applied HT of a hot-dip zinc coating results in changes in the coating’s microstructure, hardness, friction coefficient, and wear resistance.


2010 ◽  
Vol 654-656 ◽  
pp. 2763-2766 ◽  
Author(s):  
Li Wen Mu ◽  
Xin Feng ◽  
Yi Jun Shi ◽  
Huai Yuan Wang ◽  
Xiao Hua Lu

The tribological properties of polyimide (PI) composites reinforced with graphite or MoS2 sliding in liquid alkali and water as well as dry friction were investigated using a ring-on-ring tester. The results show that the friction coefficient (μ) and wear rate (W) for both graphite/PI and MoS2/PI composites in different liquid mediums are μdry>μwater >μalkali and Wwater>Wdry >Walkali. Results also indicate that the friction coefficient and wear rate of the PI composites filled with different solid lubricants are μMoS2 >μgraphite and W MoS2 >Wgraphite in different liquid mediums. In addition, the hydrophobic inorganic fillers are fit for the reinforcement of polymer-based composites sliding in liquid mediums. It is also concluded from the authors’ work that the wear rate and friction coefficient of polymer-based (such as PI, PTFE) composites in the alkali lubricated conditions is lowest among all the friction conditions. This may be attributed to the ionic hydration in the alkaline solution.


2014 ◽  
Vol 997 ◽  
pp. 321-324
Author(s):  
Wei Zheng ◽  
Guang Chun Wang ◽  
Bing Tao Tang ◽  
Xiao Juan Lin ◽  
Yan Zhi Sun

After modifying the Wahime/Bay friction model, a new friction model suitable for micro-forming process without lubrication is established. In this model, it is shows that the friction coefficient is a function of strain hardening exponent, the normal pressure and the initial yield stress of material. Based on the experimental data, the micro-upsetting process is simulated using the proposed friction model. The simulation results are used to investigate the size effect on the dry friction behavior. It is found that the Coulomb’s friction coefficient is dropping with miniaturization of specimens when the amount of reduction is not too large.


2019 ◽  
pp. 34-37
Author(s):  
Viktor Mikhailovich Yurov ◽  
Sergei Alekseevich Guchenko

In this paper, the authors propose a new approach to the consideration of the friction phenomenon in HEAs and, in particular, dry friction. An equation is obtained that shows the nonlinear dependence of the friction coefficient on Gibbs energy G0, on temperature T, on the concentration of the number of electrons N and which allows predicting the formation of high entropy alloys and coatings.


Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 635 ◽  
Author(s):  
Fang Han ◽  
Huaixing Wen ◽  
Jianjian Sun ◽  
Wei Wang ◽  
Yalong Fan ◽  
...  

This paper concerns a comparative study on the tribological properties of Si3N4-10 vol% hBN bearing on GCr15 steel under seawater lubrication and dry friction and fresh-water lubrication by using a pin-on-disc tribometer. The results showed that the lower friction coefficient (around 0.03) and wear rate (10−6 mm/Nm) of SN10/GCr15 tribopair were obtained under seawater condition. This might be caused by the comprehensive effects of hydrodynamics and boundary lubrication of surface films formed after the tribo-chemical reaction. Despite SN10/GCr15 tribopair having 0.07 friction coefficient in the pure-water environment, the wear mechanismsits were dominated by the adhesive wear and abrasive wear under the dry friction conditions, and delamination, plowing, and plastic deformation occured on the worn surface. The X-ray photoelectron spectroscopy analysis indicated that the products formed after tribo-chemaical reaction were Fe2O3, SiO2, and B2O3 and small amounts of salts from the seawater, and it was these deposits on the worn surface under seawater lubrication conditions that, served to lubricate and protect the wear surface.


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