FRICTION MECHANISM OF POLYAMIDE-6 AGAINST TIN BRONZE UNDER THE BOUNDARY LUBRICATION CONDITIONS

Additives are essential in lubricant development, improving their performance by the formation of a protective film, thus reducing friction and wear. Some such additives are extreme pressure additives. However, due to environmental issues, their use has been questioned because their composition includes sulfur, chlorine, and phosphorus. Nanoparticles have been demonstrated to be a suitable substitute for those additives. This paper aims to make a comparison of the tribological performance of conventional EP additives and oxides nanoparticles (copper and zinc) under boundary lubrication conditions. The additives (nanoparticles, ZDDP, and sulfur) were added to mineral and synthetic oils. The lubricant tribological properties were analyzed in the tribometer HFRR (high frequency reciprocating rig), and during the test, the friction coefficient and percentual of film formation were measured. The wear was analyzed by scanning electron microscopy. The results showed that the conventional EP additives have a good performance owing to their anti-wear and small friction coefficient in both lubricant bases. The oxides nanoparticles, when used as additives, can reduce the friction more effectively than conventional additives, and displayed similar behavior to the extreme pressure additives. Thus, the oxide nanoparticles are more environmentally suitable, and they can replace EP additives adapting the lubricant to current environmental requirements.

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Wear Behavior and Chemical Friction Modification in Binary-Additives System under Boundary-Lubrication Conditions

A S L E Transactions ◽

10.1080/05698198108983051 ◽

1981 ◽

Vol 24 (4) ◽

pp. 517-525 ◽

Cited By ~ 6

Author(s):

Masayuki Kagami ◽

Masataro Yagi ◽

Seiichiro Hironaka ◽

Toshio Sakurai

Keyword(s):

Boundary Lubrication ◽

Wear Behavior ◽

Lubrication Conditions

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Thin coatings with tetrahedral amorphous carbon structure and their behavior in boundary lubrication conditions

10.36652/0202-3350-2020-21-11-506-511 ◽

2020 ◽

pp. 506-511

Author(s):

V.D. Samusenko ◽

I.A. Zavidovskii ◽

O.A. Streletskii ◽

I.A. Buyanovskii ◽

M.M. Khrushchov ◽

...

Keyword(s):

Amorphous Carbon ◽

Boundary Lubrication ◽

Carbon Structure ◽

Thin Coatings ◽

Tribological Tests ◽

Tetrahedral Amorphous Carbon ◽

Structural Peculiarities ◽

Lubrication Conditions

The results of an investigation of the structural peculiarities of the thin ta-C coatings obtained by the method of impulse arc sputtering of graphite and of their tribological tests in boundary lubrication conditions are presented.

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Tribochemical Interactions of Friction Modifier and Antiwear Additives With CrN Coating Under Boundary Lubrication Conditions

Journal of Tribology ◽

10.1115/1.2961808 ◽

2008 ◽

Vol 130 (4) ◽

Cited By ~ 18

Author(s):

T. Haque ◽

A. Morina ◽

A. Neville ◽

S. Arrowsmith

Keyword(s):

Boundary Lubrication ◽

Photoelectron Spectroscopy ◽

Antiwear Additives ◽

Low Friction ◽

Friction Modifier ◽

Crn Coating ◽

Atomic Force ◽

Surface Analysis Techniques ◽

Positive Effect ◽

Lubrication Conditions

In recent years, the optimized use of low friction nonferrous coatings under boundary lubrication conditions has become a challenge to meet the demands of improved fuel economy in automotive applications. This study presents the tribological performance of chromium nitride (CrN) coating using conventional friction modifier (moly dimer) and/or antiwear additive (zinc dialkyl dithiophosphate (ZDDP)) containing lubricants in a pin-on-plate tribometer. Using surface analysis techniques such as the atomic force microscope (AFM) and X-ray photoelectron spectroscopy (XPS), both topographical and chemical analyses of tribofilms were performed. This paper shows that ZDDP and moly dimer both give a positive effect for both low friction and antiwear performance in CrN/cast iron system. Both AFM and XPS analyses give evidence of the formation of ZDDP and moly dimer derived tribofilms on the CrN coating and thus support friction and wear results.

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Tribological evaluation of piston skirt/cylinder liner contact interfaces under boundary lubrication conditions

Lubrication Science ◽

10.1002/ls.106 ◽

2010 ◽

Vol 22 (3) ◽

pp. 73-87 ◽

Cited By ~ 15

Author(s):

Nicholaos G. Demas ◽

Robert A. Erck ◽

George R. Fenske

Keyword(s):

Boundary Lubrication ◽

Cylinder Liner ◽

Piston Skirt ◽

Lubrication Conditions

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Thermal Influence on Torque Transfer of Wet Clutches in Limited Slip Differential Applications

World Tribology Congress III, Volume 2 ◽

10.1115/wtc2005-63532 ◽

2005 ◽

Cited By ~ 2

Author(s):

Pa¨r Marklund ◽

Rikard Ma¨ki ◽

Roland Larsson ◽

Erik Ho¨glund ◽

Michael M. Khonsari ◽

...

Keyword(s):

Boundary Lubrication ◽

High Load ◽

Low Velocity ◽

Thermal Influence ◽

Lubrication Conditions

Wet clutches operating under low velocity and high load are studied with the aim of obtaining reliable models for the torque transfer during boundary lubrication conditions.

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Influence of Water Absorption on Static Friction of Pure and Friction-Modified PA6 Polymers

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.799.59 ◽

2019 ◽

Vol 799 ◽

pp. 59-64

Author(s):

Igor Velkavrh ◽

Stefan Klien ◽

Joel Voyer ◽

Florian Ausserer ◽

Alexander Diem

Keyword(s):

Water Absorption ◽

Static Friction ◽

Polyamide 6 ◽

Coated Steel ◽

Friction Modifiers ◽

Test Conditions ◽

Influence Of Water ◽

Steel Surfaces ◽

Contact Pressures ◽

Lubrication Conditions

In the present study, static coefficients of friction of pure and friction modified (FM) polyamide 6 (PA6) polymers against primer-coated steel surfaces were investigated under a series of nominal contact pressures and by considering the influences of water absorption by the polymer, temperature, counter-body surface roughness and lubrication conditions. Under the majority of the test conditions investigated, FM PA6 exhibited lower static friction than pure PA6. Under unlubricated conditions, this was due to the low adhesion of the FM PA6 provided by its friction modifying inclusions; while under lubricated conditions, a combination of softening due to water absorption and decreased adhesion provided by its friction modifiers enabled lower static friction, especially at medium and high contact pressures.

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