Influence of steadite on the tribological behavior of cylinder liners

2019 ◽  
Vol 71 (2) ◽  
pp. 324-332 ◽  
Author(s):  
Tiago Cousseau ◽  
Edison Serbino ◽  
Edney Rejowski ◽  
Amilton Sinatora
Keyword(s):  
Friction And Wear ◽  
Piston Ring ◽  
Experimental Approach ◽  
Operating Conditions ◽  
Content Type ◽  
Base Oil ◽  
Real Area Of Contact ◽  
Eds Analysis ◽  
Cylinder Liners ◽  
Real Area

Purpose This paper aims to understand the effect of steadite in gray cast iron (GCI) cylinder liners performance (friction and wear) when lubricated with new lube oil formulations to verify if steadite can be reduced or suppressed from cylinder liners composition. Design/methodology/approach The paper presents an experimental approach to quantify the separated effect of lube additives and steadite content on GCI performance. Friction and wear of GCI samples with and without steadite were analyzed under lubricated conditions with a 5W30 lubricant and a base oil of similar viscosity under operating conditions similar to the ones observed at the top dead center of Otto engines. Scanning electron microscopy (SEM)-EDS analysis was used to evaluate wear and tribofilm formation. Findings The paper shows that steadite stabilizes friction coefficient and slightly reduces wear in the tests performed with base oil. However, its advantages are marginal in comparison to the ones provided by the fully formulated oil. Furthermore, SEM-EDS analyses of the wear track showed that steadite does not chemically react with zinc and sulfur compounds, reducing the tribofilm formation on the real area of contact and consequently changing the tribosystem behavior. Originality/value This paper covers an identified need to study the effect of lube additives and GCI composition using actual piston ring and cylinder liners under operating conditions similar to the ones observed at the top dead center of Otto engines.

scholarly journals Tribological performance of nano-diamond composites-dispersed lubricants on commercial cylinder liner mating with CrN piston ring

2020 ◽  
Vol 9 (1) ◽  
pp. 455-464
Author(s):  
Ruoxuan Huang ◽  
Zichun Wang ◽  
Xiaoshuai Yuan ◽  
Tianchi Zhang ◽  
Siqi Ma ◽  
...  
Keyword(s):  
Internal Combustion Engines ◽  
Friction And Wear ◽  
Piston Ring ◽  
Negative Impact ◽  
Friction Pair ◽  
Cylinder Liner ◽  
Lubricating Oil ◽  
Wear Loss ◽  
Base Oil ◽  
Cylinder Liners

AbstractThis work investigated the effect of nanodiamond (ND) additives on the tribological properties of CrN-coated piston ring mating with the chromium-plated and BP alloy iron cylinder liners, which is one of the key friction pairs in the internal combustion engines. To enhance the dispersion of the NDs in the base oil, the surface of ND particles was modified with polyaniline via in situ polymerization. The friction and wear as well as the scuffing characteristics of the friction pair lubricated with different contents of ND composite-added base oil were evaluated by using the reciprocating tribotests, which are close to the actual conditions. The wear surface morphologies and elements distribution were analyzed to explore the wear behaviors and the associated mechanisms of friction pairs under the lubrication incorporated with the ND composites. The results show that the ND additive is beneficial for the pair of Cr liner and CrN-coated piston ring in the friction and wear as well as scuffing properties, and the best concentration of ND additive is expected to be around 1 wt%. But for the BP liner, the developed nanocomposite has a negative impact. The friction force and the wear loss of the pair lubricated by the ND composite-added oil are even worse than that tested with the base lubricating oil.

Influence of MoS2, H3BO3, and MWCNT Additives on the Dry and Lubricated Sliding Tribology of AMMC–Steel Contacts

2018 ◽  
Vol 140 (4) ◽  
Author(s):  
Harpreet Singh ◽  
ParamPreet Singh ◽  
Hiralal Bhowmick
Keyword(s):  
Carbon Nanotubes ◽  
Friction And Wear ◽  
Wear Behavior ◽  
Preliminary Investigation ◽  
Multiwall Carbon Nanotubes ◽  
Operating Conditions ◽  
Matrix Composites ◽  
Base Oil ◽  
Oil Additives ◽  
Multiwall Carbon

The present study is focused on the performance evaluation of MoS2, H3BO3, and multiwall carbon nanotubes (MWCNT) used as the potential oil additives in base oil for aluminum metal matrix composites (AMMC)–steel (EN31) tribocontact. Al–B4C composite is used for this purpose; based on a set of preliminary investigation under unlubricated and fresh oil lubrication, three different types of AMMCs (Al–SiC, Al–B4C, and Al–SiC–B4C) were used. A pin-on-disk tribometer is used for all the friction and wear tests under operating condition of load 9.8 N and sliding velocity of 0.5 m/s. From the particle-based wet tribology, it is clear that both the additives H3BO3 and MWCNT improve the friction as well as wear behavior for selected composite contacts. Multiwall carbon nanotubes emerged out as superior among all the additives, whereas MoS2 additives show marginal enhancement in frictional performance under given operating conditions. Fractography and morphological study of pin specimens are carried out to identify the underlying friction and wear mechanisms.

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.

Contact Mechanics of Rough Surfaces in Tribology: Single Asperity Contact

1996 ◽  
Vol 49 (5) ◽  
pp. 275-298 ◽  
Author(s):  
Bharat Bhushan
Keyword(s):  
Friction And Wear ◽  
Rough Surfaces ◽  
Asperity Contact ◽  
Elastic Solids ◽  
Elastic Plastic ◽  
Single Asperity ◽  
Real Area Of Contact ◽  
Single Asperity Contact ◽  
Indentation Problem ◽  
Real Area

Contact modeling of two rough surfaces under normal approach and with relative motion is carried out to predict the real area of contact which affects friction and wear of an interface. The contact of two macroscopically flat bodies with microroughness is reduced to the contact at multiple asperities of arbitrary shapes. Most of deformation at the asperity contact can be either elastic or elastic-plastic. In this paper, a comprehensive review of modeling of a single asperity contact or an indentation problem is presented. Contact analyses for a spherical asperity/indenter on homogeneous and layered, elastic and elastic-plastic solids with and without tangential loading are presented. The analyses reviewed in this paper fall into two groups: (a) analytical solutions, primarily for elastic solids and (b) finite element solutions, primarily for elastic-plastic problems and layered solids. Implications of these analyses in friction and wear are discussed.

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.

Experimental study of starvation in grease-lubricated finite line contacts

2017 ◽  
Vol 69 (6) ◽  
pp. 963-969 ◽  
Author(s):  
Zhijian Wang ◽  
Xuejin Shen ◽  
Xiaoyang Chen ◽  
Qiang Han ◽  
Lei Shi
Keyword(s):  
Film Thickness ◽  
High Viscosity ◽  
Operating Conditions ◽  
Test Rig ◽  
Oil Viscosity ◽  
Content Type ◽  
Base Oil ◽  
Optical Test ◽  
Line Contacts ◽  
Finite Line

Purpose The purpose of this paper is to study starvation in grease-lubricated finite line contacts and to understand film-forming mechanisms of grease-lubricated finite line contacts. Design/methodology/approach A multiple-contact optical elastohydrodynamic (EHL) test rig is constructed to investigate the influences of lubricant properties on film thickness and lubrication conditions at different working conditions. The film thickness is calculated according to the relative light intensity principle. The degree of starvation is evaluated by the air–oil meniscus distance and the corresponding film thickness. Findings The experimental results show that for greases with high-viscosity base oil, the high-frequency fluctuation of film thickness is observed in low-speed operating conditions. Reducing the viscosity of the base oil and improving running speed can weaken the fluctuation of film thickness. The degree of starvation increases with increasing base oil viscosity, rolling speed and the crown drop. In addition, reducing the replenishment time by reducing the gap between the rollers also can increase the degree of starvation. Originality/value Starvation is often to occur in finite line contacts, such as roller bearings and gears; there are still limited finite line contact EHL test rigs, much less multiple-contact optical test rigs. Therefore, the present work is undertaken to construct the multiple-contact test rig and to evaluate the mechanism of starvation in finite line contacts.

Tribological evaluation of piston ring/cylinder liner assembly in automotive engines using GNP as a lubricant additive

2021 ◽  
pp. 095440622110553
Author(s):  
Gurtej Singh ◽  
Mohammad Farooq Wani ◽  
Mohammad Marouf Wani
Keyword(s):  
Wear Rate ◽  
Friction And Wear ◽  
Piston Ring ◽  
Film Formation ◽  
Cylinder Liner ◽  
Lubricant Additive ◽  
Operating Conditions ◽  
Power Losses ◽  
Automotive Engines ◽  
The Coefficient Of Friction

Friction and wear are the main causes of energy dissipation in automotive engines. To minimize the frictional power losses, it is extremely important to improve the tribological characteristics of ring/liner assembly which accounts for almost 40–50% frictional power losses. The present study attempts to mitigate friction and wear of the ring/liner tribo-pair using GNP/SAE 15W40 nano-lubricant. To simulate the ring/liner interface, the tribological performance of nano-lubricants was assessed using a tribometer based on ASTMG181 standard under various operating conditions. The coefficient of friction (COF) and wear rate lowered using graphene nano-lubricants (GNL). The tribological results showed that friction coefficient, wear rate, and surface roughness of piston ring improved in the range 17.71%–42.33%, 25%–40.62%, and 61%, respectively, under GNL lubricating conditions during the boundary lubrication. Further, the characterization of wear tracks of piston ring and cylinder liner confirmed tribo-film formation on worn surfaces resulting in decreased COF and wear rate.

On the lubrication characteristics of piston ring under different engine operation conditions

2019 ◽  
Vol 72 (1) ◽  
pp. 101-108
Author(s):  
Jun Sun ◽  
Xiao Zhang ◽  
Jianxiong Zhu ◽  
Yaming Gao ◽  
Hu Wang ◽  
...  
Keyword(s):  
Piston Ring ◽  
Cylinder Liner ◽  
Operating Conditions ◽  
Lubricating Oil ◽  
Cylinder Wall ◽  
Engine Operation ◽  
Operating Condition ◽  
Content Type ◽  
Lubrication Characteristics ◽  
Stroke Engine

Purpose Currently, lubrication analysis of piston ring is generally done under engine rated operating condition. However, the engine (such as the vehicle engine) does not always operate in rated operating condition, and its operating condition changes frequently in actual use. In addition, the lubrication status of piston ring is generally assumed as the flooded lubrication or a certain form of poor lubrication in most of the lubrication analysis. Design/methodology/approach In this paper, based on the equations about the flow rate of lubricating oil and the variation of control volume, the flow model of lubricating oil in the piston ring-cylinder liner conjunction is established. The lubrication analysis of piston ring for a four-stroke engine under different engine operating conditions is done, in which the lubricating oil at the inlet of piston ring is considered as the lubricating oil attached on the relevant location of cylinder wall after the piston ring moves over at the previous stroke. Findings There is remarkable difference for the lubrication characteristics of the piston ring under different engine operating conditions. The worst lubrication status of piston ring may not take place under engine rated operating condition. Originality/value In this paper, based on the measured engine cylinder pressure, the lubrication analysis of piston ring for a four-stroke engine under different engine operating conditions is done in which the lubricating oil supply condition at the inlet of piston ring is considered. The results of this paper are helpful for the design and research of engine piston ring-cylinder liner conjunction.

Effect of grooved cylinder liner depths on the tribological performances of cylinder liner-piston ring

2019 ◽  
Vol 72 (3) ◽  
pp. 465-471
Author(s):  
Chao Zhen Yang ◽  
Zhiwei Guo ◽  
Changkun Xu
Keyword(s):  
Diesel Engine ◽  
Design Methodology ◽  
Piston Ring ◽  
Cylinder Liner ◽  
Content Type ◽  
Sealing Performance ◽  
Lubrication Performance ◽  
Highly Correlated ◽  
Cylinder Liners ◽  
Groove Texture

Purpose Frictions in cylinder liner-piston ring often cause an inevitable loss of energy loss in the diesel engine. This study aims at evaluating the effect of depths in the cylinder liner groove texture on friction, wear and sealing performances. Design/methodology/approach Five depths of groove texture cylinder liners (50, 100, 150, 200, 250 µm) were fabricated, and experiments were carried out using a special-purpose diesel engine tester. Comparative analyses of cylinder liner contact resistances, piston ring wear losses and surface appearances were conducted with respect to different surface textures and applied loads. Findings Under no-load conditions, the cylinder liner with a 100 deep thread groove can significantly improve sealing and optimize its lubrication performance. On the other hand, the sealing is highly correlated with the depth of groove and the load within the cylinder liner. Under loaded conditions, the thread groove has less effect on the sealing performance. Originality/value The findings can provide feasible basis for the tribological design and production of diesel engines.

scholarly journals On the Simulation of the Micro-Contact of Rough Surfaces Using the Example of Wet Friction Clutch Materials

Lubricants ◽  
2019 ◽  
Vol 7 (5) ◽  
pp. 41 ◽  
Author(s):  
Katharina Voelkel ◽  
Markus Rothemund ◽  
Sebastian Albarracin Garibello ◽  
Vincent Kramer ◽  
Hermann Pflaum ◽  
...  
Keyword(s):  
Surface Topography ◽  
Simulation Method ◽  
Friction Material ◽  
Operating Conditions ◽  
Steel Plates ◽  
Real Surface ◽  
Friction Behavior ◽  
Real Area Of Contact ◽  
Friction Plate ◽  
Real Area

Friction behavior in a sliding contact is strongly influenced by the surface topography of the bodies in contact. This also applies to friction clutches. Even small differences in surface topography may cause significant differences in friction behavior. Thus, it is important to be able to characterize the micro-contact of the rough sliding surfaces, which are, in the case of a clutch, steel plate and friction material. One important measure for the characterization of the micro-contact is the real area of contact. Another important aspect is the contact pattern. The article introduces a method to implement a FEM (Finite Element Method) model from real surface measurements. Real surface topography of the friction pairing is considered. The simulation method is applied to different friction pairings and operating conditions. Computational results with rough and smooth steel plates, new and run-in friction linings, and different nominal surface pressure verify the model. In addition, the results on real area of contact between a steel and a friction plate are compared with published values.

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