Synthesis and tribological properties of nanogrease

2018 ◽  
Vol 70 (3) ◽  
pp. 512-518 ◽  
Author(s):  
Alaa Mohamed ◽  
Mohamed Hamdy ◽  
Mohamed Bayoumi ◽  
Tarek Osman
Keyword(s):  
Electron Microscopy ◽  
Tribological Properties ◽  
Power Efficiency ◽  
New Technologies ◽  
Mechanical Equipment ◽  
Content Type ◽  
Base Oil ◽  
X Ray ◽  
Transmission Electron ◽  
Steel Balls

Purpose To enhance the tribological properties of nanogrease, one of the new technologies was used to synthesize a nanogrease having carbon nanotubes (CNTs) nanoparticles (NPs) with different concentrations. The microstructures of the synthesized NPs were characterized and evaluated by x-ray diffraction spectroscopy (XRD) and transmission electron microscopy (TEM). Tribological properties of the nanogrease were evaluated using a four-ball tester. The worn surface of four steel balls was investigated by scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDX). Design/methodology/approach Grease was dissolved in chloroform (10 Wt.%), at 25 °C for 1 h. In parallel, functionalized CNTs with different volume concentrations (0.5, 1, 2 and 3 Wt.%) were dispersed in N, N-dimethylformamide. The mixture was stirred for 15 min and then sonicated (40 kHz, 150 W) for 30 min. After that, the mixture was added to the grease solution and magnetically stirred for 15 min and then sonicated for 2 h. Findings The results suggested that CNTs can enhance the antiwear and friction properties of nanogrease at 0.5 Wt.% CNTs to about 57 and 48 per cent, respectively. In addition, the weld load of the base oil containing 0.5 Wt.% CNTs was improved by 17 per cent compared with base grease. Originality/value This work describes the inexpensive and simple fabrication of nanogrease for improving the properties of lubricants, which improve power efficiency and extend lifetimes of mechanical equipment.

Effect of MWCNTs/Talc powder nanoparticles on the tribological and thermal conductivity performance of calcium grease

2019 ◽  
Vol 72 (1) ◽  
pp. 9-14 ◽  
Author(s):  
Ahmed Mobasher ◽  
Alaa Khalil ◽  
Medhat Khashaba ◽  
Tarek Osman
Keyword(s):  
Thermal Conductivity ◽  
Tribological Properties ◽  
Power Efficiency ◽  
Friction Reduction ◽  
Wear Testing ◽  
Mechanical Equipment ◽  
Content Type ◽  
Transmission Electron ◽  
Nano Additives ◽  
Pin On Disk

Purpose The purpose of this paper is to evaluate the influence of nanoparticles as an additive on the tribological properties of calcium grease. Design/methodology/approach The nano additives in this research are with different concentration of multi carbon nanotubes (MWCNTs) and Talc powder (1, 2, 3, 3 and 5 per cent). The ratio of MWCNTs to Talc powder is 1:1. The tribological properties of hyper MWCNTs/Talc powder to calcium grease were evaluated using a pin-on-disk wear testing. The results show that the nano additives MWCNTs/Talc to calcium grease exhibit good performance in anti-wear and friction reduction. The action mechanism was estimated through analysis of the worm surface with x-ray diffraction and transmission electron microscope. Findings The result indicates that boundary film mainly composed of MWCNT and Talc powder, and other organic compound was formed on the worm surface during the friction test. In addition, the wear rate and coefficient of friction of nanogreases have shown excellent improvement about 80.62 and 63.44 per cent, respectively, at 4 Wt.% of MWCNTs/Talc powder. Moreover, the thermal conductivity of nanogrease increased about 51.72 per cent. Originality/value This study describes the inexpensive and simple fabrication of nanogrease for improving properties of lubricants, which improve power efficiency and extend lifetimes of mechanical equipment.

Synthesis and Tribological Properties of TiSe2 Nanoparticles

2017 ◽  
Vol 45 ◽  
pp. 34-41 ◽  
Author(s):  
Qin Shi ◽  
Jing Xu ◽  
Li Feng Dang ◽  
Jun Chen ◽  
Guo Gang Tang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Reaction Time ◽  
Reaction Temperature ◽  
Tribological Properties ◽  
Raw Materials ◽  
Homogeneous Distribution ◽  
Formation Mechanisms ◽  
Base Oil ◽  
Transmission Electron

TiSe2 nanobelts/nanoplates have been successfully fabricated through a facile and environment-friendly pressureless sintered process using micro-sized Ti and Se elements as raw materials. The morphology and structure of the as-prepared TiSe2 products were investigated by X-ray diffractometer, scanning electron microscopy, transmission electron microscopy and high resolution transmission electron microscopy. The experimental results indicated that the morphology of TiSe2 products were strongly dependent on the reaction temperature and reaction time. As the reaction temperature was set at 600°C and 800°C, long belts-like and plates-like structures of as-prepared TiSe2 products could be observed, respectively. However, a mixture of nanobelts and nanoplates could be obtained at a reaction temperature of 700°C. It was also found that the reaction time played a crucial role in obtaining the homogeneous distribution nanoparticles, therefore, reasonable reaction process and formation mechanisms of as-prepared TiSe2 nanoparticles were proposed. Moreover, the tribological properties of the TiSe2 nanobelts/nanoplates were investigated. The test results showed that the addition of TiSe2 nanoparticles could improve the tribological properties of base oil. Furthermore, the friction coefficient of base oil containing TiSe2 nanoplates was lower and more stable than those of TiSe2 nanobelts and pure base oil.

scholarly journals Development of a nitrogen-doped 2D material for tribological applications in the boundary-lubrication regime

2017 ◽  
Vol 8 ◽  
pp. 1476-1483 ◽  
Author(s):  
Shende Rashmi Chandrabhan ◽  
Velayudhanpillai Jayan ◽  
Somendra Singh Parihar ◽  
Sundara Ramaprabhu
Keyword(s):  
Electron Microscopy ◽  
Tribological Properties ◽  
Photoelectron Spectroscopy ◽  
Large Scale ◽  
Synthesis Method ◽  
Field Trials ◽  
Base Oil ◽  
X Ray ◽  
Nitrogen Doped ◽  
Sliding Mechanism

The present paper describes a facile synthesis method for nitrogen-doped reduced graphene oxide (N-rGO) and the application of N-rGO as an effective additive for improving the tribological properties of base oil. N-rGO has been characterized by different characterization techniques such as X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and Raman spectroscopy. N-rGO-based nanolubricants are prepared and their tribological properties are studied using a four-ball tester. The nanolubricants show excellent stability over a period of six months and a significant decrease in coefficient of friction (25%) for small amounts of N-rGO (3 mg/L). The improvement in tribological properties can be attributed to the sliding mechanism of N-rGO accompanied by the high mechanical strength of graphene. Further, the nanolubricant is prepared at large scale (700 liter) and field trials are carried out at one NTPC thermal plant in India. The implementation of the nanolubricant in an induced draft (ID) fan results in the remarkable decrease in the power consumption.

Preparation and tribological properties of BN/calcium borate nanocomposites as additive in lubricating oil

2018 ◽  
Vol 70 (1) ◽  
pp. 105-114 ◽  
Author(s):  
Yanfei Yang ◽  
Xiaobo Wang ◽  
Sen Mei ◽  
Xing Zhu ◽  
Shiqiang Chen ◽  
...  
Keyword(s):  
Tribological Properties ◽  
Optical Microscope ◽  
Lubricating Oil ◽  
Core Shell ◽  
Calcium Borate ◽  
Wear Area ◽  
Content Type ◽  
X Ray ◽  
Friction Tester ◽  
Transmission Electron

Purpose The purpose of this paper is to investigate the tribological performance and mechanisms of BN/calcium borate nanocomposites (BCBNs) as additives in lubricating oil. Design/methodology/approach BCBNs were prepared by heterogeneous deposition method. And the morphology and structure of samples were analysed by transmission electron microscopy, Fourier transform infrared spectra and X-ray powder diffraction pattern. The maximum non-seizure load (PB) of samples was tested using four-ball friction tester. The average friction coefficients and wear tracks were obtained. In addition, tribological mechanism was also investigated using optical microscope, energy dispersive spectroscopy and X-ray photoelectron spectroscope. Findings It was found that the nanocomposites present core-shell nanostructure with the thickness of shell around 12 nm and the diameter of particles 100-200 nm, and tribological tests indicate that the PB value of BCBNs was increased by 113 per cent, whereas the average friction coefficient was decreased by 23.6 per cent and the bloom’s wear area was also decreased by 25.2 per cent. Originality/value This paper involves investigation on tribological properties and mechanism of the BCBNs with core-shell structure.

New eco-friendly anticorrosive core-shell pigments

2015 ◽  
Vol 44 (5) ◽  
pp. 276-291 ◽  
Author(s):  
Nivin M Ahmed ◽  
Walaa M. Abd El-Gawad ◽  
Elham A. Youssef ◽  
Eglal R. Souaya
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Ceramic Composites ◽  
Core Shell ◽  
Chemical Compositions ◽  
Corrosion Properties ◽  
Content Type ◽  
X Ray ◽  
Transmission Electron ◽  
Steel Substrates

Purpose – The purpose of this paper is to present the preparation of core-shell ferrites/kaolin pigments and comparing their efficiency in protecting metal substrates to original ferrites which were also prepared. Core-shell structured particles are recently gaining lots of importance due to their exciting applications in different fields; these particles are constructed from cores and shells of different chemical compositions which show ultimately distinctive properties of varied materials different from their counterparts. The new core-shell pigment is based on shell of different ferrites that comprises only 10-20 per cent of the whole pigment on kaolin (cores) which is a cheap and abundant ore that comprises 80-90 per cent of the prepared pigment. The new pigments do not only comprise two different components, but they also contain pigment and extender in the same compound; their loadings in the paint formulations ranges from 50 and 75 per cent of the whole pigment. The work showed that these eco-friendly and cheap core-shell pigments are comparable in their efficiency to that of ferrites in protecting steel substrates. Design/methodology/approach – The different ferrites and ferrites/kaolin pigments were characterized using different analytical and spectrophotometric techniques, such as X-ray fluorescence, X-ray diffraction (XRD), scanning electron microscopy/energy-dispersive X-ray (SEM/EDAX) and transmission electron microscopy (TEM). Evaluation of these pigments was done using international standard testing methods (ASTM). After evaluation, the pigments were incorporated in solvent-based paint formulations based on medium oil-modified soya-bean dehydrated castor oil alkyd resin. The physico-mechanical properties of dry films and their corrosion properties using accelerated laboratory test in 3.5 per cent NaCl for 28 days were determined. Findings – The results of this work revealed that ferrite/kaolin core-shell pigments were close in their performance to that of the ferrite pigments in protection of steel, and at the same time, they verified good physico-mechanical properties. Practical implications – Treated kaolin can be applied in many industries beside pigment manufacture and paint formulations; it can be applied as reinforcing filler in rubber, plastics and ceramic composites. Also, it is applied in paper filling, paper coatings and electrical insulation. Originality/value – Ferrite and ferrite/kaolin are environmentally friendly and can replace other hazardous pigments (e.g. chromates) with almost the same quality in their performance; also, they can be used in industries other than paints, for example paper, rubber and plastics composites.

Novel Method for Controlling Nano Thin Coatings on Particulate Materials

1998 ◽  
Vol 526 ◽  
Author(s):  
J. Fitz-Gerald ◽  
S. Pennycook ◽  
H. Gao ◽  
V. Krishnamoorthy ◽  
J. Marcinka ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Laser Ablation ◽  
New Technologies ◽  
Nano Particles ◽  
X Ray ◽  
The Core ◽  
Transmission Electron ◽  
Particulate Coatings ◽  
Core Particles

AbstractParticulate coatings have wide ranging applications in several new technologies such as flat-panel displays, sintering of advanced ceramics, rechargeable batteries, etc. In this paper, we show the feasibility of the pulsed laser ablation technique to make very thin, uniformly distributed and discrete coatings in particulate systems so that the properties of the core particles can be suitably modified. Presently, laser ablation techniques have been primarily applied to deposit thin films on flat substrate materials. To deposit discontinuous particulate coatings, the laser induced plume from the target comes in contact with an agitated bed of core particles. The pressure and nature of the background gas (inert or active) controls the cluster size of the nano particles in the laser plume. Experiments were conducted for laser deposition of Ag nano particles on Al2O3 and SiO2 core particles by pulsed excimer laser (wavelength = 248 nm and pulse duration = 25 nanosecond) irradiation of a Ag sputtering target The surface coverage and coating uniformities of the film were found to depend on the synthesis parameters (energy density, # laser pulses, gas pressure backfill gas, molecular weight) as well as the residence time of the core particles in the plume regime. The films were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), wavelength dispersive x-ray analysis (WDX), scanning transmission electron microscopy (STEM), and x-ray photoelectron spectroscopy (XPS).

scholarly journals Silicon and Phosphorus Linkage with Iron via Oxygen in the Amorphous Matrix of Gallionella ferruginea Stalks

2011 ◽  
Vol 78 (1) ◽  
pp. 236-241 ◽  
Author(s):  
Tomoko Suzuki ◽  
Hideki Hashimoto ◽  
Atsushi Itadani ◽  
Nobuyuki Matsumoto ◽  
Hitoshi Kunoh ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Degree Of Crystallinity ◽  
High Porosity ◽  
Content Type ◽  
X Ray ◽  
Transmission Electron ◽  
Primary Particles ◽  
Constituent Elements ◽  
The Degree Of Crystallinity

ABSTRACTBacterial species belonging to the genusGallionellaare Fe-oxidizing bacteria that produce uniquely twisted extracellular stalks consisting of iron-oxide-encrusted inorganic/organic fibers in aquatic environments. This paper describes the degree of crystallinity ofGallionellastalks and the chemical linkages of constituent elements in the stalk fibers. Transmission electron microscopy revealed that the matrix of the fiber edge consisted of an assembly of primary particles of approximately 3 nm in diameter. Scanning transmission electron microscopy revealed the rough granular surfaces of the fibers, which reflect the disordered assembly of the primary particles, indicating a high porosity and large specific surface area of the fibers. This may provide the surface with broader reactive properties. X-ray diffractometry, selected-area electron diffraction, and high-resolution transmission electron microscopy together showed that the primary particles had an amorphous structure. Furthermore, energy-dispersive X-ray analysis and Fourier transform infrared spectroscopy detected the bands characteristic of the vibrational modes assigned to O-H, Fe-O-H, P-O-H, Si-O-H, Si-O-Fe, and P-O-Fe bonds in the stalks, suggesting that the minor constituent elements P and Si could affect the degree of crystallinity of the fibers by linking with Fe via O. This knowledge about the mutual associations of these elements provides deeper insights into the unique inorganic/organic hybrid structure of the stalks.

Tribological properties of carbonized polydopamine/rGO composite coatings

2019 ◽  
Vol 72 (1) ◽  
pp. 54-65
Author(s):  
Ming Yang ◽  
Zhengfeng Jia ◽  
Denghu Wei ◽  
Yunxia Wang ◽  
Xianjuan Pang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Heat Treatment ◽  
Tribological Properties ◽  
Photoelectron Spectroscopy ◽  
Composite Coatings ◽  
Copper Substrate ◽  
Friction Reduction ◽  
Wear Properties ◽  
Content Type ◽  
X Ray

Purpose The purpose of this paper is to investigate the tribological properties of carbonized polydopamine/reduced graphene oxide (CPDA/rGO) composite coatings. Design/methodology/approach CPDA/rGO composite coatings were prepared using the spray technique and subsequent pyrolysis under argon. The transmission electron microscopy, field-emission scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Raman spectroscopy revealed the conversion of PDA and GO into CPDA and rGO, respectively. Findings The results of tribological investigations show that the CPDA/rGO composite coatings with heat treatment at 300°C possess much better friction-reduction and anti-wear properties. Originality/value The worn surfaces of the PDA/GO composite films after heat treatment at 300°C were much smoother than that of the copper substrate. The tribofilms containing C, N, O and Cu played an important role on reducing friction and increasing wear resistance.

Experimental Study of Nanoparticle as Oil Additives

2011 ◽  
Vol 230-232 ◽  
pp. 288-292 ◽  
Author(s):  
Yong Zhang ◽  
Xiao Jing Zhao ◽  
Qiang He ◽  
Ye Jun ◽  
Qin Po Niu
Keyword(s):  
Electron Microscopy ◽  
Experimental Study ◽  
Contact Fatigue ◽  
Test Sample ◽  
Cu Nanoparticles ◽  
Base Oil ◽  
X Ray ◽  
Oil Additives ◽  
Transmission Electron ◽  
Contact Fatigue Life

Cu nanoparticles as N32 base oil additives were studied in the paper. The structure of Cu nanoparticlcs was characterized by Transmission Electron Microscopy (TEM) and X-ray powder diffraction spectroscope (XRD). The widely used steel-steel friction system was chosen to test the feasibility and practicality of Cu nanoparticles as bearing lubricant additives. The results show that N32 base oil with 0.5% Cu nanoparticle can improve the test sample contact fatigue life than pure N32 base oil.

Phase Transformations in Ti-7w/oMo-3w/oMe Alloy

1974 ◽  
Vol 32 ◽  
pp. 514-515
Author(s):  
S. Fujishiro
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Transmission Electron Microscopy ◽  
Tensile Strength ◽  
Mechanical Processing ◽  
Ray Method ◽  
X Ray ◽  
Transmission Electron ◽  
Water Quench ◽  
Alpha Beta

The mechanical properties of three titanium alloys (Ti-7Mo-3Al, Ti-7Mo- 3Cu and Ti-7Mo-3Ta) were evaluated as function of: 1) Solutionizing in the beta field and aging, 2) Thermal Mechanical Processing in the beta field and aging, 3) Solutionizing in the alpha + beta field and aging. The samples were isothermally aged in the temperature range 300° to 700*C for 4 to 24 hours, followed by a water quench. Transmission electron microscopy and X-ray method were used to identify the phase formed. All three alloys solutionized at 1050°C (beta field) transformed to martensitic alpha (alpha prime) upon being water quenched. Despite this heavily strained alpha prime, which is characterized by microtwins the tensile strength of the as-quenched alloys is relatively low and the elongation is as high as 30%.

Sign in / Sign up

Export Citation Format

Share Document