scholarly journals Tribological Properties of Molybdenum Disulfide and Helical Carbon Nanotube Modified Epoxy Resin

Materials ◽  
2019 ◽  
Vol 12 (6) ◽  
pp. 903 ◽  
Author(s):  
Zhiying Ren ◽  
Yu Yang ◽  
Youxi Lin ◽  
Zhiguang Guo
Keyword(s):  
Elastic Modulus ◽  
Friction Coefficient ◽  
Epoxy Resin ◽  
Molybdenum Disulfide ◽  
Tribological Properties ◽  
Testing Machine ◽  
Three Dimensional ◽  
Friction Testing ◽  
Helical Carbon Nanotubes ◽  
Modified Epoxy

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.

Effects of Load and Rotate Speed on the Friction of NBR by 45# Steel in Crude Oil Medium

2011 ◽  
Vol 230-232 ◽  
pp. 1079-1083
Author(s):  
Yi Zhang ◽  
Shi Jie Wang ◽  
Zhong Feng Guo ◽  
Zhong Wei Ren
Keyword(s):  
Friction Coefficient ◽  
Crude Oil ◽  
Constant Temperature ◽  
Testing Machine ◽  
Butadiene Rubber ◽  
Nitrile Butadiene Rubber ◽  
Friction Testing ◽  
Low Load ◽  
Test Result

Select two types of nitrile-butadiene rubber (NBR) which they are different in ingredients, under two types of crude oil medium respectively, the test is carried out on the friction testing machine. The test result shows that under the constant intermediate-low rotate speed and constant temperature, the friction coefficient decreases as the load increases; under the constant intermediate-low load and constant temperature, the friction coefficient increases as the rotate speed increases.

Fabrication and Properties of Cu-Cr Coatings on the Inner Wall of Steel Pipe by Mechanical Alloying Method

2012 ◽  
Vol 602-604 ◽  
pp. 1663-1666
Author(s):  
Zhong Qing Tian ◽  
Guo Xing Zhang ◽  
Wei Jiu Huang ◽  
Yu Kai Zhu
Keyword(s):  
Friction Coefficient ◽  
Mechanical Alloying ◽  
Coating Thickness ◽  
High Speed ◽  
Testing Machine ◽  
Optical Microscope ◽  
Steel Pipe ◽  
Rotating Speed ◽  
Friction Testing ◽  
Cr Coating

The mechanical alloying method process has been innovatively used to prepare Cu-Cr coating on the inner wall of steel pipe. The effect of the rotating speed on thickness, microhardness and friction coefficient of the Cu-Cr coating was investigated. The coating thickness was measured from all samples using optical microscope. The microhardness was analyzed by Digital Microhardness Tester. The friction coefficient was tested by high speed reciprocating friction testing machine. The results show that the coating thickness is 26, 29 and 31μm at the rotating speed of 200, 250 and 300 rpm. The microhardness of the Cu-Cr coating prepared at 200, 250 and 300 rpm are about 760, 780 and 830 Hv. The friction coefficient of the Cu-Cr coating prepared at 200 rpm are about 0.25, 0.40 and 0.38 at the frequencies of 3, 4 and 5 Hz. The friction coefficient of the Cu-Cr coating prepared at 250 rpm are about 0.30, 0.29 and 0.20 at the frequencies of 3, 4 and 5 Hz. The friction coefficient of the Cu-Cr coating prepared at 300 rpm are about 0.10, 0.13 and 0.09 at the frequencies of 3, 4 and 5 Hz.

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

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.

Effect of the Prepared Proceeding on Mechanical and Tribological Properties of DLC Films

2009 ◽  
Vol 60-61 ◽  
pp. 270-273
Author(s):  
Guang Gui Cheng ◽  
Jian Ning Ding ◽  
Biao Kan ◽  
Zhen Fan
Keyword(s):  
Elastic Modulus ◽  
Friction Coefficient ◽  
Tribological Properties ◽  
Normal Load ◽  
High Hardness ◽  
Peak Shift ◽  
Frictional Material ◽  
Force Microscopy ◽  
Mechanical And Tribological Properties ◽  
Three Samples

In order to analyze the effect of proceeding on the mechanical and tribological properties of DLC films. Three DLC films samples on single silicon wafers were prepared by CVD method. The changed bias voltages were 300V, 350V, 450V separately. The structure and topography of prepared films were studied by Raman spectroscopy and atomic force microscopy (AFM), respectively. The hardness and elastic modulus together with friction coefficient of DLC films were measured by Tribolab system. According to the Raman spectra, the G and D peak shift to left with the increasing of bias voltage. Nano indent showed that the hardness (H) of the DLC films decreases from 19.63GPa to 18.12GPa with the increasing of bias voltages, and the value of elastic modulus (E) is also behaving the same trend as H from 157.95GPa to 146.95GPa. Friction coefficients of the three samples were measured by nano-scratch method under the constant normal load of 1000uN and the slide velocity of 3 um/sec, the corresponding friction coefficient is 0.0804 for DLC300, 0.0508for DLC350 and 0.0594 for DLC450 separately, which indicates that high hardness materials may not necessarily the perfect frictional material, but compound properties of hardness and elastic modulus

Investigation on Friction and Thermal Expansion Coefficients of Al-Sn Bearing Alloys

2007 ◽  
Vol 353-358 ◽  
pp. 3063-3066 ◽  
Author(s):  
Yong Zhi Zou ◽  
Zheng Bin Xu ◽  
Yan Gao ◽  
Hong Gu ◽  
Jian Min Zeng
Keyword(s):  
Thermal Expansion ◽  
Friction Coefficient ◽  
Testing Machine ◽  
Alloy System ◽  
The Other ◽  
Thermal Expansion Coefficients ◽  
Friction Testing ◽  
Other Hand ◽  
Expansion Coefficients

The influences of Sn addition of 3%-30% on the friction and thermal expansion properties of Al-Sn bearing alloys were investigated in this paper. The experiments were carried out on a specially designed friction testing machine and a dilatometer. It is shown by the experiments that the friction coefficient and hardness of the alloys decrease with the increasing of Sn content. The friction coefficient decreases dramatically when Sn content is higher than 6%. On the other hand, the friction coefficient is also dependent on the load. The friction coefficient increases as the load rises. The linear CTE is also a function of temperature and Sn contents. CTE increases when the temperature rises but has no obvious differences for the alloy system when the temperature is below 80°C. As the temperature rises, the differences become large among the alloy system. The higher the Sn content, the lower the CTE.

scholarly journals Tribological Properties of V-Shaped Surface Texture under Oil Lubrication Condition

2019 ◽  
Vol 37 (2) ◽  
pp. 401-406
Author(s):  
Yuanbo Wu ◽  
Xuefeng Yang ◽  
Shouren Wang ◽  
Jian Cheng ◽  
Hui Zhang ◽  
...  
Keyword(s):  
Friction Coefficient ◽  
Tribological Properties ◽  
Turbulence Intensity ◽  
Friction And Wear ◽  
Testing Machine ◽  
Wear Testing ◽  
Oil Lubrication ◽  
Oil Film ◽  
Texture Model ◽  
The Stability

In order to study the tribological properties of V-shaped texture under oil lubrication conditions, the loading force and speed are selected as the influencing factors, each factor selected six levels. Experimental study on friction and wear of V-shaped texture with ring arrangement is finished by MMG-10 Multifunctional Friction and Wear Testing Machine, and the data of the experimental results are analyzed by using Matlab. The results show that there is a near linear relationship between the friction coefficient and the loading force and velocity. The relationship between the friction coefficient and the loading force and velocity can be expressed by a functional equation. The loading force has a greater influence on the friction coefficient than the speed. The SEM images of the post-test specimens show that the main weared zone of the V-shaped texture is the tip part. Create a single V-shaped texture model with Solidworks and use CFD to divide the mesh into the Fluent solution. According to the pressure distribution cloud diagram and the turbulence intensity cloud diagram, the stability of the oil film is improved due to the enhanced fluidity of the oil film and the small change in the oil pressure. The tip portion is also the region with a large turbulence intensity value. The improvement of the stability of the oil film is the key to reduce the friction coefficient of the V-shaped texture when the loading force increases.

Comparison on the Tribological Properties of Roller and Guide Tribo-Pair Used in Antenna Deployable Structure

2021 ◽  
Vol 1041 ◽  
pp. 37-44
Author(s):  
Tao Feng ◽  
Tao Li ◽  
Yu Zhang ◽  
Zhuo He ◽  
Lin Wang
Keyword(s):  
High Temperature ◽  
Friction Coefficient ◽  
Carbon Fiber ◽  
Epoxy Resin ◽  
Tribological Properties ◽  
Resin Composites ◽  
Gcr15 Steel ◽  
Deployable Structure ◽  
Epoxy Resin Composites ◽  
Carbon Fiber Epoxy

The tribological properties of roller and guide tribo-pair are important for the design of deployable structure for space-borne perimeter truss antenna. In this study, carbon fiber epoxy resin composites are used as the guide material; while polyimide and GCr15 steel are used as the roller material. Then, friction coefficient of polyimide ball and GCr15 steel ball against carbon fiber epoxy resin composites disk were compared and investigated on the high-temperature, ball-on-disk tribometer under different operating conditions, respectively. The wear morphology of disk was measured by laser scanning confocal microscope. The results show that the friction coefficient of the polyimide ball against carbon fiber epoxy resin composites tribo-pair has better tribological properties. Meanwhile, the friction coefficients of this pair are mainly depend on abrasive wear under low pressure and velocity conditions while the adhesive wear has dominated influence on the friction coefficient for high pressure and velocity conditions. Besides, the tribological properties of carbon fiber epoxy resin composites are mainly affected by ploughing of surface roughness at low temperature, while by surface debonding at high temperature.

scholarly journals Deposition and Tribological Properties of Sulfur-Doped DLC Films Deposited by PBII Method

2010 ◽  
Vol 2010 ◽  
pp. 1-7 ◽  
Author(s):  
Nutthanun Moolsradoo ◽  
Shuichi Watanabe
Keyword(s):  
Elastic Modulus ◽  
Friction Coefficient ◽  
Sulfur Content ◽  
Bias Voltage ◽  
Tribological Properties ◽  
Relative Concentration ◽  
High Vacuum ◽  
Ambient Air ◽  
Flow Rate Ratio ◽  
Negative Pulse

Sulfur-doped diamond-like carbon films (S-DLC) fabricated fromC2H2andSF6mixtures were used to study the effects of sulfur content and negative pulse bias voltage on the deposition and tribological properties of films prepared by plasma-based ion implantation (PBII). The structure and relative concentration of the films were analyzed by Raman spectroscopy and Auger electron spectroscopy. Hardness and elastic modulus of films were measured by nanoindentation hardness testing. Tribological characteristics of films were performed using a ball-on-disk friction tester. The results indicate that with the increasing sulfur content, the hardness and elastic modulus decrease. Additionally, by changing the negative pulse bias voltage from 0 kV to−5 kV, the hardness and elastic modulus increase, while the friction coefficient and specific wear rate tends to decrease. Moreover, at a negative pulse bias voltage of−5 kV and flow-rate ratio of 1 : 2, there is considerable improvement in friction coefficient of 0.05 under ambient air is due to the formation of a transfer films on the interface. The decrease in the friction coefficient of films doped with 4.9 at.% sulfur is greater under high vacuum (0.03) than under ambient air (>0.1).

Influence of Boron Nitride on Tribological Behavior of Nickel-Base Composite Coatings at High Temperature

2011 ◽  
Vol 686 ◽  
pp. 711-715 ◽  
Author(s):  
Yong Kang Zhang ◽  
Jian Liang Li ◽  
Dang Sheng Xiong ◽  
Yong Kun Qin
Keyword(s):  
High Temperature ◽  
Friction Coefficient ◽  
Boron Nitride ◽  
Wear Rate ◽  
Composite Coatings ◽  
Testing Machine ◽  
Optimum Process ◽  
Wear Properties ◽  
Friction Behavior ◽  
Friction Testing

The nickel-based boron nitride composite coatings were prepared by reversing pulse electro-deposition. The mechanical properties and friction behavior of the coatings at high temperature were tested by using Al2O3 ceramic ball at high temperature friction-testing machine. The results show that the surface micro-hardness of the coatings increases with the addition of BN powder. Meanwhile, the friction coefficient and wear rate of specimens decreases. Especially when the BN addition is 1.5g/L the composite coatings present a minimum of friction coefficient and wear rate. In optimum process parameters, the friction coefficient of the coatings is about 0.2 at room temperature and 0.4-0.5 at 600°C. In addition, the friction and wear properties were significantly improved by plating Ni transition layer plated between substrate and composite coating.

Microstructure and tribological property of self-lubrication CBN abrasive composites containing molybdenum disulfide

2019 ◽  
Vol 71 (5) ◽  
pp. 712-717 ◽  
Author(s):  
Biao Zhao ◽  
Wenfeng Ding ◽  
Weijie Kuang ◽  
Yucan Fu
Keyword(s):  
Friction Coefficient ◽  
Flexural Strength ◽  
Molybdenum Disulfide ◽  
Tribological Property ◽  
Cubic Boron Nitride ◽  
Three Dimensional ◽  
Optical Microscope ◽  
Transgranular Fracture ◽  
Vacuum Sintering ◽  
Content Type

Purpose This paper aims to evaluate the influence of molybdenum disulfide (MoS2) concentrations (5, 7.5, 10, 12.5 and 15 Wt.%) on the microstructure and tribological property of the self-lubrication cubic boron nitride (CBN) abrasive composites. Design/methodology/approach Three point bending method and rotating sliding test are used to evaluate the flexural strength and tribological property of self-lubricating CBN abrasive composites. Microstructure, wear morphology of the ball and scratch are supported by scanning electron microscopy, optical microscope and three-dimensional confocal microscopy, etc. Findings The MoS2 concentration has a significant influence on the interface microstructure between CBN abrasives and matrix alloys, and thus, affects the flexural strength of CBN abrasive composites. The grain fracture modes of CBN abrasive composites are transformed from the transgranular fracture into intergranular fracture as the MoS2 concentrations increase. Additionally, the friction coefficient of as-sintered samples decreases with the MoS2 concentrations. The MoS2 concentrations of 10 Wt.% are final determined to fabricate self-lubricating composites in basis of the mechanical and lubricating property. Originality/value The ball is fabricated under vacuum sintering process. The tribological property of self-lubricating CBN abrasive composites is evaluated in terms of the friction coefficient and morphologies of the ball and scratches after rotating sliding tests.

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