Physicochemical and tribological characterizations of WDLC coatings and ionic-liquid lubricant additives: Potential candidates for low friction under boundary-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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Towards Superlubricity Under Boundary Lubrication

World Tribology Congress III, Volume 2 ◽

10.1115/wtc2005-63953 ◽

2005 ◽

Cited By ~ 2

Author(s):

J. M. Martin ◽

M. I. De Barros Bouchet ◽

T. Le Mogne ◽

M. Kano

Keyword(s):

Boundary Lubrication ◽

Automotive Industry ◽

Research Field ◽

Low Friction ◽

Carbon Coatings ◽

Dlc Coatings ◽

New Research ◽

Engine Components ◽

Potential Use ◽

Lubrication Conditions

Fuel economy and reduction of harmless elements in lubricant are becoming crucial in the automotive industry. An approach to respond these requirements in engine components is the potential use of low friction coatings exposed to specific boundary lubrication conditions. Superlubricity is a new research field in tribology, dealing with very low friction values, typically below 0.01, and this even in dry or vacuum conditions. It is to be noticed that any friction coefficient below 0.001 is hardly measurable with the equipment at hand. Superlow friction was already experimentally observed only in ultrahigh vacuum and inert gas environment, with pure molybdenite (MoS2) coatings [1] and in presence of some hydrogenated DLC coatings [2]. Under boundary lubrication, we show here that the coupling of hydrogen-free carbon coatings and selected organic lubricant additives permits to reach friction values approaching superlubricity and also a wearless behavior.

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Synergy between graphene and ionic liquid lubricant additives

Tribology International ◽

10.1016/j.triboint.2017.07.030 ◽

2017 ◽

Vol 116 ◽

pp. 371-382 ◽

Cited By ~ 39

Author(s):

José Sanes ◽

María-Dolores Avilés ◽

Noelia Saurín ◽

Tulia Espinosa ◽

Francisco-José Carrión ◽

...

Keyword(s):

Ionic Liquid ◽

Lubricant Additives ◽

Liquid Lubricant

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Process Development and Tribochemical Evaluation of Seed Oil Based Antiwear/Antifriction Additive

World Tribology Congress III, Volume 1 ◽

10.1115/wtc2005-63380 ◽

2005 ◽

Author(s):

Atanu Adhvaryu ◽

Brajendra K. Sharma ◽

Sevim Z. Erhan

Keyword(s):

Boundary Lubrication ◽

Seed Oil ◽

Process Development ◽

Mechanical Stresses ◽

Lubricant Additives ◽

Government Regulations ◽

Antifriction Additive ◽

Increasing Demand ◽

Interacting Surfaces ◽

Lubrication Conditions

Antiwear / antifriction additives enhance the ability of lubricant to withstand mechanical stresses of interacting surfaces under boundary lubrication conditions. Majority of the lubricants and additives currently used are petroleum based that are toxic to environment, making it increasingly difficult for safe and easy disposal. There has been an increasing demand for “green” lubricants and lubricant additives in recent years due to concerns about lubricants lost to the environment and increasingly strict government regulations controlling their use.

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Tribochemical Interactions of Moly Dimer and ZDDP Additives With CrN Coating and Bearing Steel While Sliding Against Cast Iron in Boundary Lubrication Conditions

ASME/STLE 2007 International Joint Tribology Conference, Parts A and B ◽

10.1115/ijtc2007-44312 ◽

2007 ◽

Author(s):

Anne Neville ◽

Tabassamul Haque ◽

Ardian Morina

Keyword(s):

Boundary Lubrication ◽

Photoelectron Spectroscopy ◽

Bearing Steel ◽

Antagonistic Effect ◽

Low Friction ◽

Crn Coating ◽

Atomic Force ◽

Lubrication Condition ◽

Increasing Demand ◽

Lubrication Conditions

In recent years, use of low friction non-ferrous coatings under boundary lubrication condition has become a challenge to meet the increasing demand of fuel economy in automotive applications. In this study, chromium nitride (CrN) was chosen as a non-ferrous coating and experiments were performed in a pin-on-plate reciprocating tribotester to produce the tribofilm. An atomic force microscope (AFM) was used to record high resolution topographical images while chemical analysis of the tribofilm was performed using X-ray photoelectron spectroscopy (XPS). Both AFM and XPS analyses give evidence of the formation of ZDDP and Moly Dimer derived tribofilm. This paper will also focus on the synergistic or antagonistic effect of ZDDP with Moly Dimer additive in the tribological performance of CrN coating.

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Effect of water on the electroresponsive structuring and friction in dilute and concentrated ionic liquid lubricant mixtures

Physical Chemistry Chemical Physics ◽

10.1039/d0cp05110a ◽

2020 ◽

Vol 22 (48) ◽

pp. 28191-28201

Author(s):

Georgia A. Pilkington ◽

Rebecca Welbourn ◽

Anna Oleshkevych ◽

Seiya Watanabe ◽

Patricia Pedraz ◽

...

Keyword(s):

Atomic Force Microscopy ◽

Ionic Liquid ◽

Neutron Reflectivity ◽

Force Microscopy ◽

Liquid Lubricant ◽

Effect Of Water ◽

Atomic Force ◽

Ambient Levels

The influence of ambient levels of water on the electroresponsive interfacial structuring and nanofriction of ionic liquid lubricant mixtures has been investigated by neutron reflectivity and atomic force microscopy.

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Comparison Between the Action of Nano-Oxides and Conventional EP Additives in Boundary Lubrication

Lubricants ◽

10.3390/lubricants8050054 ◽

2020 ◽

Vol 8 (5) ◽

pp. 54

Author(s):

Valdicleide Silva Mello ◽

Marinalva Ferreira Trajano ◽

Ana Emilia Diniz Silva Guedes ◽

Salete Martins Alves

Keyword(s):

Friction Coefficient ◽

Boundary Lubrication ◽

Friction And Wear ◽

Film Formation ◽

Environmental Issues ◽

Protective Film ◽

Extreme Pressure ◽

Extreme Pressure Additives ◽

Environmental Requirements ◽

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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Towards Phosphorus Free Ionic Liquid Anti-Wear Lubricant Additives

Lubricants ◽

10.3390/lubricants4020022 ◽

2016 ◽

Vol 4 (2) ◽

pp. 22 ◽

Cited By ~ 13

Author(s):

Anthony Somers ◽

Ruhamah Yunis ◽

Michel Armand ◽

Jennifer Pringle ◽

Douglas MacFarlane ◽

...

Keyword(s):

Ionic Liquid ◽

Lubricant Additives

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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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