Characterization of the friction and wear effects of graphene nanoparticles in oil on the ring/cylinder liner of internal combustion engine

2019 ◽  
Vol 71 (5) ◽  
pp. 642-652
Author(s):  
Selman Demirtas ◽  
Hakan Kaleli ◽  
Mahdi Khadem ◽  
Dae-Eun Kim
Keyword(s):  
Boundary Lubrication ◽  
Friction And Wear ◽  
Piston Ring ◽  
Combustion Engine ◽  
Cylinder Liner ◽  
Engine Oil ◽  
Content Type ◽  
Surface Protection ◽  
Lubrication Condition ◽  
Nano Additives

Purpose This study aims to investigate the tribological characteristics of a Napier-type second piston ring against a cylinder liner in the presence of graphene nano-additives mixed into 5W40 fully synthetic engine oil. Design/methodology/approach Wear tests were carried out in the boundary lubrication condition using a reciprocating tribometer, and real engine tests were performed using a single spark ignition Honda GX 270 test engine for a duration of 75 h. Findings The experimental results of the tribometer tests revealed that the nano-additives formed a layer on the rubbed surfaces of both the piston ring and the cylinder liner. However, this layer was only formed at the top dead center of the cylinder liner during the engine tests. The accumulation of carbon (C) from the graphene was heavily detected on the rubbed surface of piston ring/cylinder liner, mixed with other additive elements such as Ca, Zn, S and P. Overall, the use of graphene nano-additives in engine oil was found to improve the frictional behavior in the boundary and mixed lubrication regimes. Abrasive wear was found to be the main mechanism occurring on the surface of both piston rings and cylinder liners. Originality/value Though many researchers have discussed the potential benefits of graphene as a nano-additive in oil to reduce the friction and wear in laboratory tests using tribometers, to date, no actual engine tests have been performed. In this paper, both tribometer and real engine tests were performed on a piston ring and cylinder liner using a fully formulated oil with and without graphene nano-additives in the boundary lubrication condition. It was found that a graphene nano-additive plays an active role in lowering the coefficient of friction and increasing surface protection and lubrication by forming a protective layer on the rubbing surfaces.

Influence of positive texturing on friction and wear properties of piston ring-cylinder liner tribo pair under lubricated conditions

2019 ◽  
Vol 71 (4) ◽  
pp. 515-524 ◽  
Author(s):  
Venkateswara Babu P. ◽  
Ismail Syed ◽  
Satish Ben Beera
Keyword(s):  
Wear Resistance ◽  
Internal Combustion Engine ◽  
Friction And Wear ◽  
Piston Ring ◽  
Combustion Engine ◽  
Cylinder Liner ◽  
Internal Combustion ◽  
Tribological Performance ◽  
Friction Reduction ◽  
Content Type

Purpose In an internal combustion engine, piston ring-cylinder liner tribo pair is one among the most critical rubbing pairs. Most of the energy produced by an internal combustion engine is dissipated as frictional losses of which major portion is contributed by the piston ring-cylinder liner tribo pair. Hence, proper design of tribological parameters of piston ring-cylinder liner pair is essential and can effectively reduce the friction and wear, thereby improving the tribological performance of the engine. This paper aims to use surface texturing, an effective and feasible method, to improve the tribological performance of piston ring-cylinder liner tribo pair. Design/methodology/approach In this paper, influence of positive texturing (protruding) on friction reduction and wear resistance of piston ring surfaces was studied. The square-shaped positive textures were fabricated on piston ring surface by chemical etching method, and the experiments were conducted with textured piston ring surfaces against un-textured cylinder liner surface on pin-on-disc apparatus by continuous supply of lubricant at the inlet of contact zone. The parameters varied in this study are area density and normal load at a constant sliding speed. A comparison was made between the tribological properties of textured and un-textured piston ring surfaces. Findings From the experimental results, the tribological performance of the textured piston ring-cylinder liner tribo pair was significantly improved over a un-textured tribo pair. A maximum friction reduction of 67.6 per cent and wear resistance of 81.6 per cent were observed with textured ring surfaces as compared to un-textured ring surfaces. Originality/value This experimental study is helpful for better understanding of the potency of positive texturing on friction reduction and wear resistance of piston ring-cylinder liner tribo pair under lubricated sliding conditions.

The importance of 2 per cent PTFE/FeF3 additives in engine fully formulated oil for reducing friction and wear under boundary lubrication condition

2015 ◽  
Vol 67 (1) ◽  
pp. 75-80 ◽  
Author(s):  
Gabi N Nehme ◽  
Saeed Ghalambor
Keyword(s):  
Boundary Lubrication ◽  
Engine Oil ◽  
Lubricating Oil ◽  
Wear Volume ◽  
Environment Friendly ◽  
Content Type ◽  
Lubricating Oils ◽  
Engine Oils ◽  
Lubrication Condition ◽  
Minimum Wear

Purpose – This paper aims to focus on the topics of phosphorus (P) and sulfur (S) in engine oil. Very reproducible boundary lubrication tests were conducted as part of Design of Experiments software to study the behavior of fluorinated catalyst iron fluoride (FeF3) and polytetrafluoroethylene (PTFE) in the development of environment-friendly (reduced P and S) anti-wear additives for future engine oil formulations. Multi-component fully formulated oils were used with and without the addition of PTFE and fluorinated catalyst to characterize and analyze their performance. Design/methodology/approach – A boundary lubrication protocol was used in the DOE tests to study their tribological behavior. Lubricant additives like PTFE and FeF3 catalyst were used at different concentrations to investigate the wear resistance and the time for a full breakdown under extreme loading conditions. Experiments indicated that new sub-micron FeF3 catalyst plays an important role in preventing the breakdown of the tribofilm. Findings – This paper explores the effect of PTFE and FeF3 catalyst on the performance of fully formulated engine oils. The purpose was to develop equations for minimum wear volume and maximum time for full breakdown. Emphasis was, therefore, given to conditions where the additives were working effectively for minimizing zinc dialkyl dithio phosphate (P per cent). Lubricating oils are normally multi-component additivated systems. They contain different additives such as viscosity improvers, detergents, dispersants and antioxidants. It is known that these additives interact at the surface, affecting the function of the lubricating oil. Therefore, it is important to note that the performance with PTFE and FeF3 catalyst was significantly improved when compared to fully formulated commercial oils used alone. Originality/value – Lubricating oils are normally multi-component additivated systems. They contain different additives such as viscosity improvers, detergents, dispersants and antioxidants. It is known that these additives interact at the surface, affecting the function of the lubricating oil. Therefore, it is important to note that the performance with PTFE and FeF3 catalyst was significantly improved when compared to fully formulated commercial oils used alone.

Effects of surface texturing on the tribological behavior of piston rings under lubricated conditions

2016 ◽  
Vol 68 (2) ◽  
pp. 158-169 ◽  
Author(s):  
Yali Zhang ◽  
Xiaogang Zhang ◽  
Tonghai Wu ◽  
You-bai Xie
Keyword(s):  
Piston Ring ◽  
Combustion Engine ◽  
Surface Texturing ◽  
Cylinder Liner ◽  
Economic Benefits ◽  
Friction Reduction ◽  
Total Efficiency ◽  
Piston Rings ◽  
Content Type ◽  
Friction Performance

Purpose – The piston ring-cylinder liner pair is one of the most important tribological systems of an internal combustion engine. The friction loss of the piston ring-cylinder liner pair accounts for the largest portion of total efficiency losses. Therefore, improving the tribological system design of the piston ring-cylinder liner pair can reduce friction losses and bring tremendous economic benefits to society. This paper aims use surface texturing, which is proving to be an effective method, for improving the tribological performance of sliding surfaces. Design/methodology/approach – In this paper, an experimental study using a pin-on-disk tribometer was carried out to evaluate the effects of surface texturing on friction reduction of piston rings under various loads and sliding velocities. Rectangular- and circular-shaped textures with different depths and area densities were produced by a Femtosecond laser. Comparison experiments were conducted with un-textured rings. Findings – The results indicate that the friction performance of the ring surface was significantly improved by surface texturing, and the running-in stage was also shortened. More specifically, it was found that the rectangular-shaped texture had a better effect on friction reduction than the circular-shaped texture. Results also indicate that an optimum texture density existed for the rectangular-shaped texture. Additionally, it was observed that the average friction coefficient reduction of the textured ring decreased with increasing load and increased with increasing sliding velocity. Originality/value – Consequently, these findings provide a more in-depth understanding of the relationship between micro-textures and tribological properties of piston rings in lubricating sliding.

Tribological Properties of New Developed Nano Boric Acid Suspended as Additive in Engine Oil

2019 ◽  
Vol 823 ◽  
pp. 41-52
Author(s):  
Hakan Kaleli̇ ◽  
Selman Demi̇rtaş ◽  
Veli Uysal ◽  
Zulhicce Tanriseven
Keyword(s):  
Boric Acid ◽  
Photoelectron Spectroscopy ◽  
Friction And Wear ◽  
Piston Ring ◽  
Cylinder Liner ◽  
Engine Oil ◽  
Lubricating Oil ◽  
Chemical Compositions ◽  
X Ray ◽  
Liner System

It is well known that nanoparticles affect the interaction between lubricants and surfaces with various chemical compositions and different chemical and physical properties. In recent years, nanoparticles have started to play more important roles as lubricant additives for their potential in wear, friction and emission reduction and improving lubrication and fuel economy. Although nanolubricants are frequently used for friction tests, little is known about stability and degree of dispersion of these nanoparticles in viscous liquids. Most of them are unstable, agglomerate or aggregate which sediment over time. Boric acid (H3BO3) has always been a very important material due to its broad range of applications such as in medicine, cosmetics, automotive industry, metallurgy and also for miscellaneous purposes in other areas. Literature survey showed that friction between automobile engine parts could be greatly reduced using microscopic particles of boric acid.This study involves the new invention of successful suspension of nano boric acid (BA) additive added into 5W-40 fully synthetic commercial lubricating oil. This invention is confidential and realized by Murat ÖZAYMAN from Tribor ARGE Co. in Teknopark of YILDIZ Technical University in Istanbul-TURKEY. The particle size of BA is determined with (Transmission Electron Microscopy) (TEM). Backscattering and transmittance profiles proved that nano boric acid (BA) particles were in suspension in commercial engine oil. Suspended BA in engine oil is applied between piston ring and cylinder liner system in order to investigate their effect on friction and wear under boundary lubricated conditions. Simulation and measurement of friction and wear were conducted using a reciprocating tribometer. Surface analysis were performed using 3D digital optical microscope, Field Emission Scanning Electron Microscope (FESEM)/X-Ray, X-ray photoelectron spectroscopy (XPS) and Atomic Force Microscopy (AFM). Boron (B) from BA is well detected, mixed with other elements of additives and protected the surface under boundary lubrication conditions. The results indicate that BA can considerably improve the tribological performance of a piston ring and cylinder liner system under lubricated conditions. It has found that the friction coefficient is reduced with nano boric acid (BA) suspended engine oil and protected the surface mostly on cylinder liner mixing with other additives.

Synergistic effects of electroless piston ring coatings and nano-additives in oil on the friction and wear of a piston ring/cylinder liner pair

Wear ◽  
2019 ◽  
Vol 422-423 ◽  
pp. 201-211 ◽  
Author(s):  
Yufu Xu ◽  
Quan Zheng ◽  
Jian Geng ◽  
Yinghui Dong ◽  
Ming Tian ◽  
...  
Keyword(s):  
Friction And Wear ◽  
Piston Ring ◽  
Synergistic Effects ◽  
Cylinder Liner ◽  
Nano Additives

scholarly journals Investigation on the application of YAG laser texturing technology to the cylinder wall of auto engine

2014 ◽  
Vol 66 (3) ◽  
pp. 387-392 ◽  
Author(s):  
Jian Zhan ◽  
Mingjiang Yang
Keyword(s):  
Wear Rate ◽  
Piston Ring ◽  
Discrete Distribution ◽  
Cylinder Liner ◽  
Cylinder Wall ◽  
Laser Texturing ◽  
Yag Laser ◽  
Content Type ◽  
The Coefficient Of Friction ◽  
Lubrication Condition

Purpose – The purpose of this study was to develop a new approach using a pulse YAG laser with rational power density and pulse width to texture desired discrete distribution morphology on the cylinder wall. Design/methodology/approach – Variational rules of the effects of these three parameters were found by calculating the oil film on the cylinder/piston ring system. The experiment results were compared between laser texturing cylinders and conventional honing cylinders. Findings – It was found that the coefficient of friction and wear rate of laser texturing cylinders were reduced by 50 and 85.7 per cent, respectively, and the piston ring wear rate was decreased by 50 per cent under full lubrication condition. Under starved lubrication condition, the cylinder liner wear was reduced by 34.3 per cent. Originality/value – The effectiveness of which was determined by three control parameters: depth-to-diameter ratio, area density and distribution angle of the dimples.

Tribotest of engine piston ring/cylinder liner pairs with different nanoparticles added into engine oil

2018 ◽  
Vol 72 (2) ◽  
pp. 217-231
Author(s):  
Selman Demirtas ◽  
Hakan Kaleli ◽  
Mahdi Khadem ◽  
Dae-eun Kim
Keyword(s):  
Carbon Nanotubes ◽  
Internal Combustion Engines ◽  
Piston Ring ◽  
Cylinder Liner ◽  
Internal Combustion ◽  
Economic Life ◽  
Engine Oil ◽  
Combustion Engines ◽  
Content Type ◽  
Walled Carbon Nanotubes

Purpose Wear on internal combustion engines is a loss of material that occurs with the rubbing of the materials in contact with each other and significantly reduces the economic life of the engine. Even the smallest precaution that can be taken to prevent friction and wear in the engines can provide economical savings in very large quantities. Internal combustion engines are widely utilized in modem automobiles. Around 10 per cent of the total fuel energy is dissipated to heat due to mechanical friction, among which 20 per cent is caused by the contact between the cylinder liner and the piston rings. Design/methodology/approach In this study, real piston ring-cylinder specimens were tested with reciprocating tribometer by using five different nanoparticles added to engine oil to investigate their wear and friction behavior. Findings With regard to the experiments, it has been found that the best results were determined by TiO2 and single-walled carbon nanotubes according to boron nitride, multi-walled carbon nanotubes and graphene nanoparticles added to the engine oil, respectively. At the end of the tests, different wear mechanisms have been determined after the surface analyses on the piston ring and cylinder liner surface, and abrasive wear has been observed as the main wear mechanism. Originality/value This paper has an originality with regard to adding different nanoparticles into the commercial engine oil.

Study on Wear Mechanism of Chromium Carbide Coating Reinforced Cast Iron Cylinder Sleeve

2013 ◽  
Vol 273 ◽  
pp. 124-128
Author(s):  
Zi Bo Ye ◽  
Sheng Guan Qu ◽  
Yong Hu ◽  
Guang Hong Wang
Keyword(s):  
Cast Iron ◽  
Piston Ring ◽  
Combustion Engine ◽  
Tensile Force ◽  
Cylinder Liner ◽  
Tribological System ◽  
Lubrication Condition ◽  
Worn Surface ◽  
Cylinder Sleeve ◽  
Dynamic Coefficient Of Friction

In tribological system of internal combustion engine, cylinders and pistons were in high temperature, pressure and load working status. An SRV IV wear tester was used to measure dynamic coefficient of friction by simulating working condition of cylinder liner and piston ring. The worn surface topography was observed through scanning electron microscope and metallography. The results show that loads had little effect on the friction coefficient under oil lubrication. Cylinder with the high-chromium carburizing ring in pairs displayed wear in the form of plastic deformation, while cylinder with the phosphide cast iron ring in pairs displayed adhesive wear. The piston ring was subjected to shear stress and tensile force under dry friction condition and deformed into tapering burr. Lubricants played a bearer role under lubrication condition; therefore, surface borderline of piston ring was relatively flat.

scholarly journals Wear of different material pairings for the cylinder liner – piston ring contact

2018 ◽  
Vol 70 (4) ◽  
pp. 687-699 ◽  
Author(s):  
Thomas Wopelka ◽  
Ulrike Cihak-Bayr ◽  
Claudia Lenauer ◽  
Ferenc Ditrói ◽  
Sándor Takács ◽  
...  
Keyword(s):  
Steady State ◽  
Wear Mechanisms ◽  
Piston Ring ◽  
Cylinder Liner ◽  
Wear Behaviour ◽  
Special Focus ◽  
Intermediate Step ◽  
Piston Rings ◽  
Content Type ◽  
Cylinder Liners

Purpose This paper aims to investigate the wear behaviour of different materials for cylinder liners and piston rings in a linear reciprocating tribometer with special focus on the wear of the cylinder liner in the boundary lubrication regime. Design/methodology/approach Conventional nitrided steel, as well as diamond-like carbon and chromium nitride-coated piston rings, were tested against cast iron, AlSi and Fe-coated AlSi cylinder liners. The experiments were carried out with samples produced from original engine parts to have the original surface topography available. Radioactive tracer isotopes were used to measure cylinder liner wear continuously, enabling separation of running-in and steady-state wear. Findings A ranking of the material pairings with respect to wear behaviour of the cylinder liner was found. Post-test inspection of the cylinder samples by scanning electron microscopy (SEM) revealed differences in the wear mechanisms for the different material combinations. The results show that the running-in and steady-state wear of the liners can be reduced by choosing the appropriate material for the piston ring. Originality/value The use of original engine parts in a closely controlled tribometer environment under realistic loading conditions, in conjunction with continuous and highly sensitive wear measurement methods and a detailed SEM analysis of the wear mechanisms, forms an intermediate step between engine testing and laboratory environment testing.

A scuffing model considering additive depletion in boundary lubrication

2019 ◽  
Vol 72 (3) ◽  
pp. 267-272
Author(s):  
Bora Lee ◽  
Yonghun Yu ◽  
Yong-Joo Cho
Keyword(s):  
Boundary Lubrication ◽  
Mass Conservation ◽  
Additive Concentration ◽  
Contact Conditions ◽  
Sliding Bearings ◽  
Content Type ◽  
Proposed Model ◽  
Lubrication Condition ◽  
Scuffing Failure ◽  
Sliding Distance

Purpose This paper aims to propose a new scuffing model caused by the depletion of additives in boundary lubrication condition. Design/methodology/approach The differential equation governing the distribution of additive content in the fluid film was used. This formula was derived from the principle of mass conservation of additives considering the consumption due to surface adsorption of wear particles. The occurrence of scuffing was determined by comparing the wear rate of the oxide layer with the oxidation rate. Findings If the additive becomes depleted while sliding, the scuffing failure occurs even at a low-temperature condition below the critical temperature. The critical sliding distance at which scuffing failure occurred was suggested. The experimental data of the existing literature and the theoretical prediction using the proposed model are shown to be in good agreement. Originality/value It is expected to be used in the design of oil supply grooves for sliding bearings operating under extreme conditions or in selecting the minimum initial additive concentration required to avoid scuffing failure under given contact conditions.

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