Structural criterion for the antiwear properties of lube oils

2007 ◽  
Vol 43 (3) ◽  
pp. 211-218
Author(s):  
V. T. Kostygov
Keyword(s):  
Structural Criterion ◽  
Antiwear Properties

scholarly journals An Investigation on Tribological Properties and Lubrication Mechanism of Graphite Nanoparticles as Vegetable Based Oil Additive

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Yu Su ◽  
Le Gong ◽  
Dandan Chen
Keyword(s):  
Friction Coefficient ◽  
Tribological Properties ◽  
Volume Fraction ◽  
Wear Volume ◽  
Lubrication Mechanism ◽  
Step Method ◽  
Antiwear Properties ◽  
Physical Deposition ◽  
Graphite Nanoparticles ◽  
Friction Reducing

This paper used graphite nanoparticles with the diameter of 35 and 80 nm and LB2000 vegetable based oil to prepare graphite oil-based nanofluids with different volume fractions by two-step method. The tribological properties of graphite nanoparticles as LB2000 vegetable based oil additive were investigated with a pin-on-disk friction and wear tester. Field emission scanning electron microscope (FE-SEM) and energy dispersive spectroscopy (EDS) were used to examine the morphology and the content of some typical elements of wear scar, respectively. Further, the lubrication mechanism of graphite nanoparticles was explored. It was found that graphite nanoparticles as vegetable based oil additive could remarkably improve friction-reducing and antiwear properties of pure oil. With the increase of volume fraction of graphite nanoparticles, the friction coefficient and the wear volume of disk decreased. At the same volume fraction, the smaller particles, the lower friction coefficient and wear volume. The main reason for the improvement in friction-reducing and antiwear properties of vegetable based oil using graphite nanoparticles was that graphite nanoparticles could form a physical deposition film on the friction surfaces.

Surface Reactions of Extreme Pressure Additive on Steel Surface in Ceramics-Steel Couples

1988 ◽  
Vol 110 (3) ◽  
pp. 394-401 ◽  
Author(s):  
Y. Tanita ◽  
F. Honda ◽  
K. Nakajima
Keyword(s):  
Steel Surface ◽  
Iron Phosphate ◽  
Atomic Ratio ◽  
Sliding Contact ◽  
Chemical Compositions ◽  
Reaction Products ◽  
Antiwear Properties ◽  
Zinc Dithiophosphate ◽  
Steel Surfaces ◽  
Constituent Elements

The behavior of zinc dithiophosphate (ZnDTP) is investigated for the antiwear properties in SiC-steel and Si3N4-steel sliding contact systems under boundary lubrication. Reaction products formed on the steel surfaces under the sliding contact differ in the chemical compositions and the thickness between these couples. These differences are specifically related to the physical properties of mating materials such as heat conductivity and friction coefficient. The reaction products are analyzed by SEM (scanning electron microscope), EPMA (electron probe microanalysis), AES (Auger electron spectroscope), and PAS (photoacoustic spectroscopy), and it is confirmed that iron phosphate for SiC-steel and iron phosphate and zinc sulfide (or some complex compound containing equal amounts of Zn and S in atomic ratio) for Si3N4-steel couple exist on the steel surface, respectively. An examination is conducted on steel-steel couple in comparison with ceramics-steel couples, and the atomic ratio (Zn:P:S) of the constituent elements of the reaction products coincides fairly with that of SiC-steel couple.

New approaches to the design of analgesic medicinal substances

2021 ◽  
Author(s):  
Ilya V. Rogachevskii ◽  
Vera B. Plakhova ◽  
Valentina A. Penniyaynen ◽  
Stanislav G. Terekhin ◽  
Svetlana A. Podzorova ◽  
...  
Keyword(s):  
Functional Groups ◽  
Receptor Binding ◽  
Therapeutic Potential ◽  
Medicinal Substance ◽  
Neuron Membrane ◽  
Comenic Acid ◽  
Structural Criterion ◽  
Calcium Cations ◽  
Medicinal Substances ◽  
Living Neurons

A gamma-pyrone derivative, comenic acid, activates the opioid-like receptor-mediated signaling pathway that modulates the NaV1.8 channels in the primary sensory neuron membrane. These channels are responsible for generation of the nociceptive signal; gamma-pyrones can therefore have a great therapeutic potential as analgesics, and this effect deserves a deeper understanding. The novelty of our approach to the design of a medicinal substance is based on a combination of the data obtained on living neurons using very sensitive physiological methods and the results of quantum-chemical calculations. This approach allows to correlate the molecular structure of gamma-pyrones with their ability to evoke a physiological response of the neuron. Comenic acid can bind two calcium cations. One of them is chelated by the carbonyl and the hydroxyl functional groups, while another one forms the salt bond with the carboxylate anion. Calcium-bound gamma-pyrones are fundamentally different in electrostatic properties from the free gamma-pyrone molecules. These two calcium ions are the key elements involved in ligand-receptor binding. It is very likely ion-ionic interactions between these cations and anionic functional groups of the opioid-like receptor that activate the latter. The calculated intercationic distance of 9.5 Å is a structural criterion for effective ligand-receptor binding of calcium-bound gamma-pyrones.

scholarly journals Tribological behavior of oils additised with a phosphonium-derived ionic liquid compared to a commercial oil

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Marlene Bartolomé Sáez ◽  
Antolin E. Hernández Battez ◽  
Jorge Espina Casado ◽  
José L. Viesca Rodríguez ◽  
Alfonso Fernández-González ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Peer Review ◽  
Formation Rate ◽  
Antiwear Additives ◽  
Stribeck Curve ◽  
Content Type ◽  
Base Oil ◽  
Base Oils ◽  
Antiwear Properties ◽  
Commercial Oil

Purpose The purpose of this paper is to study the antifriction, antiwear and tribolayer formation properties of the trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl) phosphinate ionic liquid (IL) as additive at 1 wt.% in two base oils and their mixtures, comparing the results with those of a commercial oil. Design/methodology/approach The mixture of the base oils used in the formulation of the commercial oil SAE 0W20 plus the IL was tested under rolling/sliding and reciprocating conditions to determine the so-called Stribeck curve, the tribolayer formation and the antifriction and antiwear behaviors. Findings The use of this IL as additive in these oils does not change their viscosity; improves the antifriction and antiwear properties of the base oils, making equal or outperforming these properties of the SAE 0W20; and the thickness and formation rate of the tribolayer resulting from the IL-surface interaction is highly dependent on the type of base oil and influence on the friction and wear results. Originality/value The use of this IL allows to replace partial or totally commercial antifriction and antiwear additives. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2020-0179/

scholarly journals The Synergistic Antiwear Performances of Organic Titanium Compounds Containing Sulfur with Borate Ester Additive

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Xin Xu ◽  
Jian-Qiang Hu ◽  
Feng Xie ◽  
Li Guo ◽  
Jun Ma ◽  
...  
Keyword(s):  
Effective Interaction ◽  
Extreme Pressure ◽  
X Ray ◽  
Borate Ester ◽  
Load Carrying ◽  
Antiwear Properties ◽  
Chemical States ◽  
Titanium Compounds ◽  
Scanning Electron ◽  
Mineral Base

Two oil-soluble organic titanium compounds (OTCs) such as titanium dialkyldithiocarbamate (TiDDC) and sulfurized titanate (TiS) were synthesized and identified by Fourier-transform infrared spectroscopy (FTIR). The antiwear and extreme pressure properties of TiDDC or TiS with borate ester containing nitrogen (BNO) additive in mineral base oils were evaluated by four ball tester. The results show that TiDDC and TiS not only possess good antiwear and load-carrying properties, respectively, but also exhibit good antiwear synergism with BNO additive without impairing extreme pressure performances. Moreover, the synergistic antiwear properties of the said additives are improved significantly under the optimum additives ratios. The topography of wear scar and the composition and chemical states of typical elements on the rubbing surfaces were analyzed by scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) and X-ray photoelectron spectrometer (XPS). The proposed synergistic antiwear mechanism involves an effective interaction between TiDDC or TiS and BNO additive, respectively.

Effect of graphite or carbon black on the antiwear properties of silicone lubricants

1970 ◽  
Vol 6 (12) ◽  
pp. 929-931
Author(s):  
R. I. Kobzova ◽  
I. V. Shul'zhenko ◽  
V. A. Mikheev ◽  
S. Yu. Omarov
Keyword(s):  
Carbon Black ◽  
Antiwear Properties
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