Conductive capacity and tribological properties of several carbon materials in conductive greases

2016 ◽  
Vol 68 (5) ◽  
pp. 577-585 ◽  
Author(s):  
Zhengfeng Cao ◽  
Yanqiu Xia ◽  
Xiangyu Ge
Keyword(s):  
Electron Microscope ◽  
Tribological Properties ◽  
Friction And Wear ◽  
Volume Resistivity ◽  
Lubricant Additive ◽  
Step Method ◽  
Content Type ◽  
X Ray ◽  
The Coefficient Of Friction ◽  
Complex Lithium

Purpose The purpose of this paper is to synthesize a new kind of conductive grease which possesses a prominent conductive capacity and good tribological properties. Design/methodology/approach A two-step method was used to prepare complex lithium-based grease. Ketjen black (KB), acetylene black (AB) and carbon black (CB) were characterized by transmission electron microscope and used as lubricant additives to prepare conductive greases. Conductive capacity was evaluated by a conductivity meter, a surface volume resistivity meter and a circuit resistance meter. Tribological properties were investigated by a reciprocating friction and wear tester (MFT-R4000). The worn surfaces were analyzed by a scanning electron microscope, Raman spectroscopy, energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscope. Findings The conductive grease prepared with KB has a prominent conductive capacity at room temperature, 100°C and 150°C. Further, this conductive grease also possesses better tribological properties than AB and KB greases. When the concentration of KB is 1.8 Wt.%, the coefficient of friction and wear width reduced by 11 and 14 per cent, respectively. Originality/value This work is a new application of nanometer KB as a lubricant additive in grease, which provides a direction for preparing conductive grease. The conductivity and tribology experiments have been carried out though the variation of experiment conductions.

scholarly journals Study of tribological properties of epoxy and resins composites under technically dry friction conditions

2018 ◽  
Vol 19 (12) ◽  
pp. 658-661
Author(s):  
Sylwester Stawarz ◽  
Magdalena Stawarz ◽  
Robert Gumiński ◽  
Wojciech Kucharczyk
Keyword(s):  
Coefficient Of Friction ◽  
Tribological Properties ◽  
Dry Friction ◽  
Friction And Wear ◽  
Surface Condition ◽  
Selective Transfer ◽  
X Ray ◽  
Tribological Tests ◽  
Transfer Phenomenon ◽  
The Coefficient Of Friction

The article discusses the results of tribological tests of epoxy and resol composites. There was examined the surface condition of samples of composites operating in sliding nodes. It has been found that it is possible to use cheaper resole resins for sliding composites (instead of Epidian 5). Tests that have been carried out showed that increasing the PTFE content in the composite resulted in lowering both the coefficient of friction and wear. X-ray analysis results con-firmed the occurrence of the selective transfer phenomenon

Experimental investigation on the tribological property of functionalized graphene lubricant against steel

2020 ◽  
Vol 72 (3) ◽  
pp. 307-314
Author(s):  
Yong Qian ◽  
Hongying Gong ◽  
Xiaoyun Zhao ◽  
Lei Cao ◽  
Weizhong Shi ◽  
...  
Keyword(s):  
Peer Review ◽  
Coefficient Of Friction ◽  
Tribological Properties ◽  
Substrate Surface ◽  
Lubricant Additive ◽  
Functionalized Graphene ◽  
Experimental Conditions ◽  
Content Type ◽  
The Coefficient Of Friction ◽  
Modified Graphene

Purpose The purpose of this study is to corroborate the advanced tribological properties of graphene as a lubricant additive. Design/methodology/approach Different concentrations of functionalized graphene were coated on the substrate surface. Tribological properties of the graphene lubricants were carried out by ball-on-disk tribology tests. Wear mechanism of functionalized graphene was studied by observing wear scars on the substrate surface. Finally, the wear resistance of modified graphene was calculated by calculating and analyzing the applied experimental conditions and the obtained experimental data. Findings The best concentration of graphene lubricant is 0.5 wt.% which shows the best tribological performance. And the coefficient of friction is 0.08. Compared with the dry friction condition, the coefficient of friction and wear rate of best graphene lubricant decreased by 80% and 82%. Originality/value The formula of graphene lubricant is independently developed and works very well. Graphene lubricant can prevent the substrate from oxidation. The thickness of the graphene lubricant is about 4-7µm. The concept of anti-wear strength was introduced in this paper. When 0.5 Vol.% graphene was added, the anti-wear strength was greatly improved from 115.3 kg·mm-2 to 657.6 kg·mm-2. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2019-0344

Tribological properties of beef tallow as lubricating grease

2017 ◽  
Vol 69 (5) ◽  
pp. 645-654 ◽  
Author(s):  
Juozas Padgurskas ◽  
Raimundas Rukuiža ◽  
Ihor Mandziuk ◽  
Arturas Kupcinskas ◽  
Katerina Prisyazhna ◽  
...  
Keyword(s):  
Critical Load ◽  
Tribological Properties ◽  
Beef Tallow ◽  
Friction And Wear ◽  
Load Level ◽  
Synthesis Process ◽  
Polymer Additives ◽  
Lubricating Grease ◽  
Content Type ◽  
Thermally Processed

Purpose The purpose of this paper is to report on the tribological properties of beef tallow grease and improvements therein through modification with special processing, polymeric compounds and additives. Design/methodology/approach Pure original beef tallow grease was used as a biological lubricating grease reference material for the tribological research. Beef tallow was modified and synthesized by adding special biological anti-oxidant additives, LZ anti-wear additives, waste polyethylene terephthalate (PET) polymer compounds and thermally processed graphite. Findings Rheometric measurements indicate that the beef tallow grease modification technology used in this study enables control of the synthesis process to produce lubricants with the required microstructure. Investigation results of the tribological properties of differently modified greases show that beef tallow synthesized with polymer additives efficiently operates together with anti-wear additives to reduce friction and wear. The grease compound with thermally processed graphite has good tribological properties at 300 N load levels. The critical load level of lubricating greases could be significantly increased through the use of anti-wear additives and thermally processed graphite. Originality/value Investigation results of the tribological properties of differently modified beef tallow greases show that beef tallow synthesized with polymer additives efficiently operates together with anti-wear additives to reduce friction and wear. The critical load level of lubricating beef tallow greases could be significantly increased using anti-wear additives and thermally processed graphite.

Tribological properties of the epoxy resin-based solid lubricant coating modified by Kevlar fibers

2018 ◽  
Vol 70 (9) ◽  
pp. 1706-1713 ◽  
Author(s):  
Guotao Zhang ◽  
Yanguo Yin ◽  
Ting Xie ◽  
Dan Li ◽  
Ming Xu ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Epoxy Resin ◽  
Tribological Properties ◽  
Dry Friction ◽  
Friction And Wear ◽  
Solid Lubricant ◽  
Transfer Film ◽  
Wear Properties ◽  
Content Type ◽  
Friction And Wear Properties

Purpose This paper aims to obtain high mechanical and good tribological properties of epoxy resin-based coatings under dry friction conditions. Design/methodology/approach Bonded solid lubricant coatings containing Kevlar fibres were prepared by a spraying method. The friction and wear properties of the coatings were experimentally investigated with a face-to-face tribometre under dry friction conditions. Scanning electron microscopy, energy dispersive X-ray spectroscopy and 3D laser scanning technologies were used to characterise the tribological properties. The action mechanism of the Kevlar fibres on a solid lubricant transfer film was also analysed. Findings Adding Kevlar fibres can significantly improve the wear resistance of the coatings. When the Kevlar fibre content increases, the tribological properties of the coatings improve and then worsen. Superior properties are obtained with 0.03 g of Kevlar fibres. Appropriately increasing the load or speed is beneficial to the removal of the outer epoxy resin and the formation of a lubricant film. During friction, the solid lubricants wrapped in the epoxy resin accumulate on the surface to form a transfer film that shows a good self-lubricating performance. In the later friction stage, fatigue cracks occur on the solid lubricant film but cannot connect to one another because of the high wear resistance and the entanglement of the rod-like Kevlar fibres. Thus, no large-area film falls from the matrix, thereby ensuring the long-term functioning of solid lubricant coatings. Originality/value Epoxy resin-based solid lubricant coatings modified by Kevlar fibres were prepared, and their friction and wear properties were investigated. Their tribological mechanisms were also proposed. This work provided a basis for the analysis of the tribological properties and design of bonded solid lubricant coatings containing Kevlar fibres.

Microstructure and Tribological Properties of Cu-Fe Based Braking Materials

2014 ◽  
Vol 941-944 ◽  
pp. 280-283
Author(s):  
Xiao Yang Wang ◽  
Hong Qiang Ru
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Tribological Properties ◽  
X Ray Diffraction ◽  
Pressing Method ◽  
X Ray ◽  
The Coefficient Of Friction ◽  
Worn Surface ◽  
Scanning Electron ◽  
Sic Particle

SiC particle-reinforced Cu-Fe based braking materials were fabricated by the P/M hot pressing method. The phase composition, microstructure and the worn surface of the composite were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD).The tribological properties were evaluated using a disk-on-disk type laboratory scale dynamometer. Results indicate that the friction coefficient is 0.42 in 6800rpm, 0.7MPa. With the increase of rotation speeds the coefficient of friction and stable rate were decreased.

scholarly journals The tribological properties study of carbon fabric/ epoxy composites reinforced by nano-TiO2 and MWNTs

Open Physics ◽  
2018 ◽  
Vol 16 (1) ◽  
pp. 1127-1138 ◽  
Author(s):  
Fengjun Wei ◽  
Bingli Pan ◽  
Juan Lopez
Keyword(s):  
Tribological Properties ◽  
Friction And Wear ◽  
Epoxy Composite ◽  
Good Effect ◽  
Binder Phase ◽  
Carbon Fabric ◽  
Wear Properties ◽  
Brittle Rupture ◽  
Composites Materials ◽  
The Coefficient Of Friction

Abstract A kind of carbon fabric/epoxy composite was successfully prepared with carbon fiber fabric as reinforced phase and epoxy resin as binder phase, then the nano-TiO2 and a hybrid system of TiO2/MWNTs was added into the carbon fabric/ epoxy composite matrix respectively to prepare a kind of nano-composite. The friction and wear properties of CF/EP composites under different load conditions have been studied in this article, during the study the effects of filler types and contents on the tribological properties were researched, at last the worn surfaces were investigated and the abrasion mechanism was discussed. The results showed that: whether filling the nano-TiO2 alone or mixing the TiO2/MWNTs, it was able to achieve a good effect on decreasing friction and reducing wear, and the optimum addition ratio of the nano-TiO2 particles was 3.0% , meanwhile 3.0% of nano-TiO2 and 0.4% of MWNTs could cooperate with each other in their dimension, and could show a synergistic effect on modifying the tribological properties of CF/EP composites, the coefficient of friction of the modified composites decreased by 20% and the wear life increased by more than 140% compared with that of pristine composite materials, in the process of friction and wear, the wear form of the composites materials varied from brittle rupture to abrasive wear gradually.

Investigating the structure, adhesion and tribological properties of Al and Zr-doped TiN coatings with various substrate bias voltage and working pressure

2020 ◽  
pp. 135065012094007
Author(s):  
Yaşar Sert ◽  
Tevfik Küçükömeroğlu ◽  
İhsan Efeoğlu
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Tribological Properties ◽  
Surface Hardness ◽  
Closed Field ◽  
X Ray Diffraction ◽  
Working Pressure ◽  
Substrate Bias Voltage ◽  
X Ray ◽  
Scanning Electron

In this study, TiAlZrN films were coated on the hardened 1.2344 (X 40 CrMoV 5 1) steels using DC power supplied closed field unbalanced magnetron sputtering (CFUBMS) technique. Structural investigations of coatings were carried out using scanning electron microscope and X-ray diffraction. The thickness of coatings was measured from the cross-sectional scanning electron microscope images, and the grain size value and residual stress were calculated by using X-ray diffraction data in the Scherrer formula. Nano indentation method was used to investigate the surface hardness for reducing the substrate effect due to very thin coating thickness (∼2–3 µm). Scratch test was performed for determining the adhesion strength of the coatings. As a tribo-test, a ball-on-disk system was used. From the results, it was understood why TiAlZrN coatings were attractive. The highest hardness was observed as 50.67 GPa, and the highest scratch resistance was reached to 56 N. Also, it was determined that the coating having the highest tribological properties (5.46 × 10−5 mm3/Nm) increased the wear resistance of the substrate six times (3.06 × 10−4 mm3/Nm).

SAC–xTiO2 nano-reinforced lead-free solder joint characterizations in ultra-fine package assembly

2018 ◽  
Vol 30 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Fakhrozi Che Ani ◽  
Azman Jalar ◽  
Abdullah Aziz Saad ◽  
Chu Yee Khor ◽  
Roslina Ismail ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Solder Joint ◽  
Solder Joints ◽  
Ion Beam ◽  
Lead Free ◽  
Lead Free Solder ◽  
Solder Paste ◽  
Content Type ◽  
X Ray ◽  
Free Solder

Purpose This paper aims to investigate the characteristics of ultra-fine lead-free solder joints reinforced with TiO2 nanoparticles in an electronic assembly. Design/methodology/approach This study focused on the microstructure and quality of solder joints. Various percentages of TiO2 nanoparticles were mixed with a lead-free Sn-3.5Ag-0.7Cu solder paste. This new form of nano-reinforced lead-free solder paste was used to assemble a miniature package consisting of an ultra-fine capacitor on a printed circuit board by means of a reflow soldering process. The microstructure and the fillet height were investigated using a focused ion beam, a high-resolution transmission electron microscope system equipped with an energy dispersive X-ray spectrometer (EDS), and a field emission scanning electron microscope coupled with an EDS and X-ray diffraction machine. Findings The experimental results revealed that the intermetallic compound with the lowest thickness was produced by the nano-reinforced solder with a TiO2 content of 0.05 Wt.%. Increasing the TiO2 content to 0.15 Wt.% led to an improvement in the fillet height. The characteristics of the solder joint fulfilled the reliability requirements of the IPC standards. Practical implications This study provides engineers with a profound understanding of the characteristics of ultra-fine nano-reinforced solder joint packages in the microelectronics industry. Originality/value The findings are expected to provide proper guidelines and references with regard to the manufacture of miniaturized electronic packages. This study also explored the effects of TiO2 on the microstructure and the fillet height of ultra-fine capacitors.

Study of Tribological Properties of Multilayer Ti/TiN Coating Containing Stress Absorbing Layers

2020 ◽  
Vol 142 (11) ◽  
Author(s):  
Amod Kashyap ◽  
A. P. Harsha ◽  
Harish C. Barshilia ◽  
Venkataramana Bonu ◽  
Praveen Kumar V. ◽  
...  
Keyword(s):  
Tribological Properties ◽  
Wear Behavior ◽  
Multilayer Coating ◽  
Considerable Change ◽  
Wear Volume ◽  
Significant Drop ◽  
X Ray ◽  
Paraffin Oil ◽  
The Coefficient Of Friction ◽  
Steel Balls

Abstract Titanium (Ti)/titanium nitride (TiN) ultrathin multilayer coating was deposited on 100Cr6 substrates to investigate the friction and wear behavior in the presence of paraffin oil as a lubricant. The coating architecture was designed by adding thick stress absorbing layers (SAL ∼320 nm) in between the ultrathin Ti/TiN (3.5/4 nm) multilayer structure. The SAL reduces the residual stress in the coating. The coating had a NaCl type of structure, and X-ray diffraction (XRD) results showed the preferential crystallographic orientation of TiN along [111] direction. The tribological properties of the nanostructured coating were evaluated under reciprocating sliding conditions at varying loads (2 and 7 N), and temperature (30 and 100 °C) against 100Cr6 steel balls using paraffin oil as a lubricant. There was no considerable change in the coefficient of friction (COF) at different testing parameters. However, there was a significant drop in wear volume at high-temperature testing conditions. The worn tracks were analyzed for their morphology and elemental composition through scanning electron microscope (SEM), energy dispersive X-ray analysis (EDAX), and Raman spectroscopy.

Some Tribological Properties of an Ionic Liquid

2005 ◽  
Author(s):  
Takashi Nogi
Keyword(s):  
Ionic Liquid ◽  
Coefficient Of Friction ◽  
Tribological Properties ◽  
Friction And Wear ◽  
Wear Performance ◽  
Lubrication Regime ◽  
Pin On Disc ◽  
The Coefficient Of Friction

Some tribological properties of an ionic liquid were investigated by using a pin-on-disc friction and wear tester. Due to running-in, the coefficient of friction of the ionic liquid decreased with time to a very low value of 0.02 which suggests that the lubrication regime was hydrodynamic at the end of the tests. Anti-wear performance of the ionic liquid was substantially comparable to a paraffin-based oil.

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