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Volume-4, Issue-4, August-2014, ISSN No.: 2250-0758

International Journal of Engineering and Management Research Available at: www.ijemr.net

Page Number: 250-263

Wear and Friction in Journal Bearing: A Review

Sanjay Kumar1, S.S. Sen

2

1M. Tech Student, Green Hills Engineering College, Kumarhatti, Solan, INDIA

2Professor, Green Hills Engineering College, Kumarhatti, Solan, INDIA

ABSTRACT

The importance of friction and wear control cannot

be overemphasized for economic reasons and long-term

reliability. The savings can be substantial, and these savings

can be obtained without the deployment of investment. These

advances provide the impetus for research aimed at

developing a fundamental understanding of the nature and

consequences of the interactions between materials on the

atomic scale, and they guide the rational design of material

for technological applications.This paper presents the reviews

of different works in the area of wear and friction in journal

bearings and tries to find out latest developments and trends

available in industries and other fields in order to minimize

the total equipment cost, minimize damages and maximize

the safety of machines, structures and materials.

Keywords-- Wear, Friction, Literature Review, Summary

of Literature Review and Conclusion

I. INTRODUCTION

Despite their presence in our everyday life,

friction, wear and tribology are not phenomena that most

peoples are considering on daily basis. Nevertheless, they

are responsible for many problems and large cost in

modern civilization and engineers and designers are

always must take these factors into account when

constructing technical equipment.Variables in friction and

wear testing are load, velocity, contact area, surface finish,

sliding distance, environment, material of counter face,

type of lubricant, hardness of counter face and

temperature. Usually wear is undesirable, because it makes

necessary frequent inspection and replacements of parts

and also it will lead to deterioration of accuracy of

machine parts. It can induce vibrations, fatigue and

consequently failure of the parts. For the particular

practical application the kind of wear loading can be

different, and therefore the structure of the composite

material used for these applications can also be different in

order to fulfill the particular requirements [1].

As soon as two bodies are in mutual mechanical

contact and they are forced to slide against each other there

will frictional force between them, directed exactly

opposite to sliding direction [2]. Even though certain

amount of friction often is necessary there are many

applications where friction coefficient should be as low as

possible. Friction is an important factor in many

engineering disciplines. Rail adhesion refers to the grip

wheels of a train have on the rails. Road slipperiness is an

important design and safety factor for automobiles Split

friction is a particularly dangerous condition arising due to

varying friction on either side of a car.Road texture affects

the interaction of tires and the driving surface. A

tribometer is an instrument that measures friction on a

surface. A profilograph is a device used to measure

pavement surface roughness. A number of material-

processing strategies have been used to improve the wear

performance of polymers. This has prompted many

researchers to cast the polymers with fiber/fillers.

Considerable efforts are being made to extend the range of

applications. Various researchers have studied the

tribological behavior of FRPCs. Studies have been

conducted with various shapes, sizes, types and

compositions of fibers in a number of matrices. In general

these materials exhibit lower wear and friction when

compared to pure polymers. An understanding of the

friction and wear mechanisms of FRPC’s would promote

the development of a new class of materials. Use of

inorganic fillers dispersed in polymeric composites is

increasing.

1.2 Tribology

Tribology is defined as the science and

technology of interacting surfaces in relative motion,

having its origin in the Greek word tribos meaning rubbing

[3]. It is the study of the friction, lubrication and wear of

engineering surfaces with a view of understanding surface

interactions in detail and then prescribing improvements in

given applications. Since World War II the rapid rate of

technological advancement has required great expansion in

research on what to do about surfaces that rub. One of the

important objectives in Tribology is the regulation of the

magnitude of frictional force according to whether we

require a minimum or a maximum. This objective can be

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realized only after a fundamental understanding of the

frictional process is obtained for all conditions of

temperature, sliding velocity, lubrication, surface finish

and material properties.

Many polymers and polymer based composites

are widely used for sliding couples against metals,

polymers and other materials. However, where the contact

is there, there is the problem of friction and wear. The

friction between polymers can be attributed to two main

mechanisms, deformation and adhesion. In this case, the

deformation mechanism involves complete dissipation of

energy in the contact area while the adhesion component is

responsible for the friction of polymer and is a result of

breaking of weak bonding forces between polymer chains

in the bulk of the material. In fact, tribologists often

classify thermoplastic polymeric materials into three

distinct groups according to their friction and wear

behavior. These are: the normal polymers such as low-

density polyethylene (LDPE), (PMMA); and the smooth

molecular profile polymers such as Polytetrafluoroethylene

(PTFE) and ultra-high molecular weight polyethylene

(UHMWPE). Among them, the better frictional

performance of the smooth molecular profile polymers can

be explained by the easiness with which the long chain

molecules shear across each other.

1.3 Industrial Significance of Tribology

Tribology is crucial to modern machinery which

uses sliding and rolling surfaces. Examples of productive

friction are brakes, clutches, driving wheels on trains and

automobiles, bolts, and nuts. Examples of productive wear

are writing with a pencil, machining, polishing, and

shaving. Examples of unproductive friction and wear are

internal combustion and aircraft engines, gears, cams,

bearings, and seals. According to some estimates, losses

resulting from ignorance of tribology amount in the United

States to about 6% of its gross national product (or about

$200 billion dollars per year in 1966), and approximately

one-third of the world's energy resources in present use

appear as friction in one form or another. Thus, the

importance of friction reduction and wear control cannot

be overemphasized for economic reasons and long-term

reliability. According to Jost [1] (1966, 1976), the United

Kingdom could save approximately 500 million pounds

per annum, and the United States could save in excess of

16 billion dollars per annum by better tribological

practices. The savings are both substantial and significant,

and these savings can be obtained without the deployment

of large capital investment.

II. FRICTION AND WEAR

2.1 Friction

Friction is the resistance to relative tangential

motion between the two solid bodies or surfaces in contact

with each other. Friction always acts in direction opposite

to that of motion.

The friction exists:

1) When an attempt is made to initiate the motion: &

2) During the motion.

2.1.2 Laws of Friction

The classic laws of friction are as follows:

Friction force is proportional to loadCoefficient of friction

is independent of apparent contact area.

Static coefficient is greater than the kinetic coefficient and

Coefficient of friction independent of sliding speed.

The first law, commonly referred as Coulomb’s law is

correct except at high pressure. It generally takes form

F = W.

Where,

F is the friction force,

is the coefficient of friction,

W is the normal load.

The second law is appears to be valid only for

materials possessing a definite yield point (metals), and it

does not apply to elastic and visco elastic materials.

The third law is not obeyed by any visco elastic

material.

The fourth law is not valid for any material,

however visco elastic properties are dominant then this law

is obeyed to some extent.

2.1.3 Types of Friction

Based On Status Of Relative Motion:

Static Friction: The friction between contacting surfaces

at the start of relative motion is known as static friction

Kinetic Friction: The friction between contacting surfaces

during relative motion is known as dynamic friction

Based On Type Of Relative Motion:

Sliding Friction: The friction between contacting surfaces

having relative sliding motion is known as sliding friction.

Rolling Friction: The friction between contacting surfaces

having relative rolling motion is known as rolling friction.

Based On Lubrication between Contacting Surfaces:

Dry Friction: If no lubrication is provided between

contacting surfaces, the friction is dry friction.

Boundary Friction: The friction between the contacting

surfaces which are separated by one or more molecular

layers of lubricants is known as boundary friction.

Fluid (Viscous) Friction: The friction between the

contacting surfaces which are separated by fluid film is

known as fluid (viscous) friction.

2.1.4 Causes of Friction

Adhesion:When two surfaces are pressed together, the

contact occurs at the asperities on the two contacting

surfaces. The real area of contact between two surfaces is

very small & the large area is separated by the distance

which is more compared to molecular range of action. The

real area of contact, which is range of 0.01 % to25 % of

the gross area, depends upon the surface roughness of load.

It is directly proportional to load. As the load is carried by

the point of contact can be estimated by measuring the

electrical resistance across the surface of the metal when

they are in contact. Due to the extremely high pressure, tip

of the softer material deforms plastically & plastic flow

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causes the real area of contact to grow. At the area of

plastic deformation, the contact pressure is so high that the

contacting surfaces get cold-welded. This cold-welding

between contacting surfaces is known as adhesion. Deformation:In addition to adhesion, the friction is also

due to deformation of contacting surfaces. When two

surfaces are in sliding contact, the asperities on harder

surface & entrapped wear particles penetrate & plough in

to softer surface. This ploughing not only increases friction

but also creates wear particles

Combined Effect: The friction between two surfaces is

due to combined effect of adhesion & deformation. The

total frictional force equal to additional frictional force due

to adhesion & deformation. 2.2 Wear

2.2.1 Introduction Wear is progressive loss or removal of material

from one or both the surfaces in contact as the result of

relative motion between them.Wear is the single most

influencing factor which shortens the effective life of

machine or its components.

2.2.2 Types of Wear

Fig. 1 Types of Wear

Abrasive Wear Abrasive wear occurs when material is removed

from one surface by another harder Material, leaving hard

particles of debris between the two surfaces. It can also be

called scratching, gouging or scoring depending on the

severity of wear. Abrasive wear occurs under two

conditions:

1. Two body abrasion: In this condition, one surface is

harder than the other rubbing surface as shown in figure

(a). Examples in mechanical operations are grinding,

cutting, and machining.

2. Three body abrasion: In this case a third body, generally

a small particle of grit or abrasive, lodges between the two

softer rubbing surfaces, abrades one or both of these

surfaces, as shown in figure (b).

Fig 2 Abrasive Wear

Erosive Wear The impingement of solid particles, or small

drops of liquid or gas often cause what is known as erosion

of materials and components. Solid particle impact erosion

has been receiving increasing attention especially in the

aerospace industry. Examples include the ingestion of sand

and erosion of jet engines and of helicopter blades. As

shown in figure the erosion mechanism is simple. Solid

particle erosion is a result of the impact of a solid particle

A, with the solid surface B, resulting in part of the surface

B been removed. The impinging particle may vary in

composition as well as in form. The response of

engineering materials to the impingement of solid particles

or liquid drops varies greatly depending on the class of

material, materials properties (dependent on thermal

history, exposure to previous stresses or surface tensions),

and the environmental parameters associated with the

erosion process, such as impact velocity, impact angle, and

particle size / type. Cavitation erosion occurs when a solid

and a fluid are in relative motion, due to the fluid

becoming unstable and bubbling up and imploding against

the surface of the solid, as shown in figure 4. Cavitation

damage generally occurs in such fluid-handling machines

as marine propellers, hydrofoils, dam slipways, gates, and

all other hydraulic turbines, according to Bhushan and

Gupta (1991) [4]. Cavitation erosion roughens a surface

much like an etchant would.

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Fig 3 Abrasive Wear due to solid erosionFig 4 Abrasive

Wear due to liquid erosion

Adhesive Wear

Adhesive wear is often called galling or scuffing,

where interfacial adhesive junctions lock together as two

surfaces slide across each other under pressure, according

to Bhushan and Gupta (1991) [4]. As normal pressure is

applied, local pressure at the asperities become extremely

high. Often the yield stress is exceeded, and the asperities

deform plastically until the real area of contact has

increased sufficiently to support the applied load, as shown

in figure. In the absence of lubricants, asperities cold-weld

together or else junctions shear and form new junctions.

This wear mechanism not only destroys the sliding

surfaces, but the generation of wear particles which cause

cavitation and can lead to the failure of the component. An

adequate supply of lubricant resolves the adhesive wear

problem occurring between two sliding surfaces.

Fig 5 Adhesive Wear

Surface Fatigue

When mechanical machinery move in periodical

motion, stresses to the metal surfaces occur, often leading

to the fatigue of a material. All repeating stresses in a

rolling or sliding contact can give rise to fatigue failure.

These effects are mainly based on the action of stresses in

or below the surfaces, without the need of direct physical

contact of the surfaces under consideration. When two

surfaces slide across each other, the maximum shear stress

lies some distance below the surface, causing microcracks,

which lead to failure of the component. These cracks

initiate from the point where the shear stress is maximum,

and propagate to the surface as shown in figure. Materials

are rarely perfect, hence the exact position of ultimate

failure is influenced by inclusions, porosity, microcracks

and other factors. Fatigue failure requires a given number

of stress cycles and often predominates after a component

has been in service for a long period of time.

Fig 6 Surface Fatigue

Corrosive Wear

In corrosive wear, the dynamic interaction

between the environment and mating material surfaces

play a significant role, whereas the wear due to abrasion,

adhesion and fatigue can be explained in terms of stress

interactions and deformation properties of the mating

surfaces. In corrosive wear firstly the connecting surfaces

react with the environment and reaction products are

formed on the surface asperities. Attrition of the reaction

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products then occurs as a result of crack formation, and/or

abrasion, in the contact interactions of the materials. This

process results in increased reactivity of the asperities due

to increased temperature and changes in the asperity

mechanical properties.

III. OBJECTIVES

To find out the behavior of the material from wear &

friction point of view and the effect of various sliding

speeds and loads.

To study the phenomenon of failure of transfer film by

making use of SEM or optical microscope.

To suggest the best suitable material for the journal

bearing applications from the tested materials.

IV. LITERATURE SURVEY

A test method to determine the friction and wear

coefficients of bearing material-steel couples under

conditions of boundary lubrication is described [5]. Test

results obtained with three different test rigs in three

laboratories show the validity of the proposed test method.

The results are believed to contribute to the

characterization of materials for specific technical

applications and the test method is thus proposed for

standardization procedures of the International

Organization for Standardization.

Shyam Bahadur[6] observed that transfer films

are formed in sliding between polymer and polymer as

well as polymer and metal. In the former case, material

transfer occurs from a polymer of low cohesive energy

density to one of higher cohesive energy density. Inorganic

particulate materials used as the fillers in polymers may

either increase or decrease its wear resistance. Wear

depends upon the cohesion of transfer film, adhesion of

transfer film to the counter face, and the protection of

rubbing polymer surface from metal asperities by transfer

film.

Voong et al.[7] were examined the wear

properties of Al–Si alloys used in the crankshaft bearings

of internal combustion engines under two fully formulated

lubricants, which have the same viscosity grade. It was

found that in a completely ferrous‐based system fully

formulated lubricants are effective in reducing wear and

friction.

Yuji Yamamoto &, Masaaki Hashimoto

[8]proved that, under boundary or mixed lubricating

conditions, with 18 vol. % carbon fiber-reinforced PEEK

and PPS, the fiber orientation affected the wear resistance.

The fibers aligned perpendicular to sliding direction

exhibited higher wear resistance than those parallel to

sliding direction Yuji Yamamoto& Masaaki Hashimoto

were studied the friction and wear characteristics of fiber-

reinforced PEEK and PPS in water using a face-contact

sliding tester. The fibers used were glass and carbon fibers.

Under boundary lubricating conditions, PEEK reinforced

with glass fiber was little improved in friction and wear

characteristics, since both PEEK and glass fiber had poor

resistance to wear in water.

Das and Biswas[9]were examined the tribology

properties of Al–Si alloys under the lubricants with

additives. They analyzed the data in terms of the formation

of a mechanically mixed layer at the interface and the

corrosive action of additive addition.

Ertugrul Durak [10]was studying the effects of

addition of rapeseed oil to the base oil on the friction

coefficient in the journal bearing under static loading at

different temperatures. The rapeseed oil is added to a

mineral‐based lubricant acts as an additive that decreases

the friction coefficient at high journal speeds, and even at

medium loads.

Klaus Friedrich, Zhong Zhang, & Alois K.

Schlarb [11]have observed during the wear test that , if the

particle sizes of the filler material used in PTFE are

diminishing down to Nano-scale, significant improvements

of the wear resistance of polymers were achieved at very

low Nano-filler content (1–3 vol.%). A combinative effect

of nanoparticles with short carbon fibers exhibited a clear

improvement of the wear resistance of both thermosetting

and thermoplastic composites. A topographic smoothening

and a possible rolling effect due to the nanoparticles are

running-in supposed to be the reason for this progress in

the friction and wear performance.

Gwidon W. Stachowiak et al[12] describes the

fundamental wear mechanisms operating in non-metallic

materials together with some prognoses concerning the

future developments of these materials. Two classes of

materials with entirely different characteristics—polymers

and ceramics—are discussed. Polymers can provide low

friction and low wear coefficients but their use is limited to

lower temperatures and consequently low speeds and

loads. Ceramics are resistant to high temperatures and

often have a good wear resistance but their applications are

limited by poor friction coefficients, especially in

unlubricated applications. Ceramics and polymers are

surprisingly vulnerable to accelerated wear in the presence

of corrosive reagents and care should be taken in the

selection of materials that are appropriate for particular

operating conditions.

H. Unal , A. Mimaroglu , U. Kadýoglu , H. Ekiz

[13] has studied and explored the influence of test speed

and load values on the friction and wear behavior of pure

Polytetrafluoroethylene (PTFE), glass fiber reinforced

(GFR) and bronze and carbon (C) filled PTFE polymers.

Friction and wear experiments were run under ambient

conditions in a pin-on-disc arrangement. Tests were

carried out at sliding speed of 0.32 m/s, 0.64 m/s, 0.96 m/s

and 1.28 m/s and under a nominal load of 5 N, 10 N, 20 N

and 30 N. Therefore, the reinforcement PTFE with glass

fibers improves the load carrying capability that lowers the

wear rate of the PTFE. For the specific range of load and

speed explored in this study, the load has stronger effect on

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the wear behavior of PTFE and its composites than the

sliding velocity.

Hernandez Battez et al. [14]were discussed the

extreme‐pressure behavior of Nano particle suspensions in

a polyalphaolefin. The Nano particles of CuO, ZnO and

ZrO2 were dispersed at 0.5, 1.0 and 2.0 wt. % in PAO 6

using an ultrasonic probe during 2 min in four ball wear

tester. The wear scar diameter (WSD) was measured using

an optical microscope and scanning electron microscopy

and energy dispersive spectrometry. From the analysis of

the worn surface all concentrations of Nano particles

improved the extreme properties of PAO 6 and CuO Nano

particles exhibited the best extreme property behavior.

Wu et al. [15] were examined the tribological

properties of two lubricating oils with CuO, TiO2, and

Diamond nanoparticles used as additives. The results

shown that the nanoparticles especially CuO, added to

standard oils exhibit good friction‐reduction and anti‐wear

properties. The addition of CuO nanoparticles in the

engine oil and the base oil decreased the friction

coefficient and reduced the worn scar depth compared to

the one without CuO nanoparticles.

The friction and wear properties of polyamide 66

(PA66), polyphenylene sulfide (PPS) and

polytetrafluoroethylene (PTFE) sliding against themselves

under dry sliding and oil-lubricated conditions were

studied by using a pin-on-disc tribometer[16]. The effect

of applied load and sliding speed on tribological behaviors

of the polymer–polymer sliding combinations under dry

sliding and oil-lubricated conditions were also

investigated. The worn surfaces were examined by using

Scanning Electron Microscope (SEM). Experimental

results showed that friction properties of the three sliding

combinations could be greatly improved by oil lubrication,

the antiwear properties of PTFE and PPS were improved

by oil lubrication, while that of PA66 were decreased by

oil lubrication.

Bekir Sadik Unlu and Enver Atik [17]were

investigated friction coefficient of bronze radial bearings

by a new approach. The result shows that high friction

coefficient and high wear have been observed in dry test

conditions and the lubricated conditions have low friction

coefficient and low wear have been observed.

E. Feyzullahoglu et al.[18] discussed the

tribological behavior of tin based alloys and brass in oil

lubricated conditions. It is shown that the performance of

brass under oil lubrication is better than tin based alloys

due to its hardness. The wear in brass is lower than the

tin‐based alloys under similar tribological loading

conditions.

Yu et al.[19] were studied friction and wear

properties of copper Nano particles. The morphologies,

typical element distribution and chemical states of the

worn surfaces were characterized by SEM, EDS and XPS,

respectively. The results indicate that the higher the oil

temperature applied, the better the tribological properties

of Cu Nano particles.

Yu et al.[20] were investigated copper Nano

particles dispersed in SN 650 oil to improve the lubricating

properties of the oil. The result shown that the

friction‐reducing and anti‐wear properties of SN 650 oil

have been improved by adding Cu Nano particles.

It is well known that in journal bearings, friction

occurs in all lubrication regimes. However, shaft

misalignment in rotating systems is one of the most

common causes of wear. In this work, the bearing is

assumed to operate in the hydrodynamic region, at high

eccentricities, wear depths, and angular misalignment [21].

As a result, the minimum film thickness is 5–10 times the

surface finish, i.e., near the lower limit of the

hydrodynamic lubrication when taking into account that in

the latest technology CNC machines the bearing surface

finish could be less than 1–2 μm.An analytical model is

developed in order to find the relationship among the

friction force, the misalignment angles, and wear depth.

Erol Feyzullahoglu et al[22]were examined, the

tribological behaviors of different polymer journal

bearings during the working period with steel shaft at dry

friction conditions. Journal bearings are produced by

different engineering plastics .Bearing and shaft are

studied at dry friction conditions in journal bearing

experiment apparatus. The friction force is obtained on

contact surface. The friction and wear behaviors of

bearings are affected by speed, load, and temperature and

working time. The wear and friction behaviors of Devateks

and Ertalyte are superior to Ertacetal and Ertalon 6PLA

according to test results.

According to J.D. Bressana et al [23] the disc

wear was more severe as the difference in hardness

between pin and disc increased. It can be observed that the

decrease in the pin hardness yields to lower pin wear

resistance distance the trend of the pin wear rate curves

with the sliding distance is approximately constant and

linear. However, in the final stage, some pins presented the

tendency to decrease the wear rate. This is due the

decrease in the real contact pressure with the increase of

the pin contact area and/or increase in the hardness of the

disc track.

According to G. Zhanga, et al. [24] the sliding

velocity plays significant roles on the tribological

characteristics by influencing the interface temperature and

strain rate of the PEEK surface layer involved in the

friction process. The applied load influences the

tribological performance by varying the strain range in the

surface layer.

According to A. Hernandez Battez, et al [25]all

nanoparticle suspensions exhibited friction and wear

reduction compared to the base oil. ZrO2 and ZnO

suspensions exhibited similar friction and wear behavior as

a function of nanoparticle content, which contrasts with

CuO. The suspensions with 0.5% of ZnO and ZrO2 had

the best general tribological behavior, exhibiting high

friction and wear reduction values. However, CuO

suspensions had the highest friction coefficient and lowest

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wear for the same nanoparticle content (2%). An increase

of nanoparticle concentration in base oil increases

deposition on wear surfaces.

In this study, the tribological behavior of

Cr2O3/Ni8.5Cr7Al5Mo2Si2B2FeTiO2 coatings for

bearing materials was investigated in dry and acid

conditions[26]. Flame spray technique was used in order to

deposit coating materials onto AISI 304L steel substrate.

The wear experiments were performed under dry and acid

environments using a pin-on-plate configuration against

AISI 303 counter material for different loads. It was found

that in acid environment, the amount of wear loss is less

than that of in dry condition and applied load level is more

effective in dry condition. In SEM study, the effect of

plastic deformation of adherent and compacted debris

particles on friction of the coatings was investigated.

Crankshaft main bearings are subjected to various

stresses. A new material supposed to be adapted these

operating conditions was designed composing of Pb–Sn–

Cu–ZrO2 and manufactured by HVOF spraying technique.

Wear behavior of the bearing was tested with the

simulation of real operating conditions. An original

bearing was used for comparison. After a trial of 500 h, the

weight losses were measured. SEM micrographs of both

original and new bearings were examined. The effect of

micro hardness was discussed[27]. The new composition

was seen as promising as a bearing material for automotive

engines.

Y. Choi et al.[28] were investigated the friction

coefficient for raw oil and Nano‐oil mixed with copper

Nano particles by using a disc‐on‐disc tribotester. The

result shown that the average friction coefficient of raw oil

and Nano oil under a load of 3000 N is decreased by 44 %

and 39 % respectively.

Boncheol Ku et al [29] were examined the

comparative tribological behavior of journal bearings

made from polytetrafluoroethylene composites and

aluminum alloys. The tribological properties of journal

bearings were evaluated as a function of the applied

normal load by measuring the temperature of lubricating

oil and coefficient of friction. The results showed that the

Al alloy journal bearings reduce the friction coefficient by

28 % compared to the PTFE composite bearings and the

PTFE composite journal bearings exhibited strong

adhesion at the loads ranging from 6300 to 8000 N. Based

on this experiment the Al alloy is a more promising

material in journal bearings than PTFE composites.

Jiang and Xie[30]were investigated the

tribological behavior of plasma‐spray TiO2 coating pairing

with conventional metallic bearing materials and triphenyl

thiophosphate and tricresyl phosphate. The results shown

that the copper– lead alloy paired with TiO2 coating

lubricated with the base oil exhibited the optimum

tribological performance.

Ramesh Kumar et al.[27] studied the mechanical

and tribological properties of plain bearing alloys used in

internal combustion engines. The wear and sliding friction

of aluminum‐tin alloy against high carbon high chromium

steel were experimented at different loads in lubricated

conditions with a sliding speed of 1 m/s. They found that

the friction and wear value of aluminum alloy bearings is

less than that of pure aluminum bearing.

The effects of process and material parameters on

the coefficient of friction in the flat-die test were

examined[32]. Low carbon steel, a hot-dip galvanized steel

and Extra Gal™, another hot-dip galvanized steel were

used in the tests. As the die surface roughness increased,

the coefficient of friction increased most of the time.

Under some conditions an optimum roughness was

evident. The bare steel produced the highest coefficient of

friction in the majority of the tests. The speed and load

effects, found in other applications, have been confirmed,

in general: the coefficient decreased for increases in load

and speed in most cases.

A novel method for measuring the interfacial

coefficient of friction between two solids which avoids

sliding is described, and sample results are given[33]. The

technique makes use of the fact that a carefully controlled

sequence of partial slip states between contacting bodies

may be used to produce relative motion whose extent is a

strong function of the coefficient of friction. It is argued

that this approach induces much less surface damage in the

components, and therefore yields a value for the

coefficient of friction which is much more representative

of their unmodified condition.

Erol Feyzullahoglu et al [34] were investigated

aluminum‐based alloys produced by metal mould casting

and analyzed tribological properties of these alloys under

lubrication. The experiments were carried out at pressures

of 0.231–1.036 N/mm2 and sliding speeds at 0.6– 2.4 m/s.

The results showed that the friction and wear behavior of

the alloys have changed according to the sliding

conditions. Al8.5Si3.5Cu alloy has a lower friction

coefficient value than other alloys.

This work reports on the structural and wear

properties of a range of engineering coatings including

TiN, TiAlN, CrAlN, MoS2/Ti and a number of different

DLC coatings, deposited on tool steel substrates[35]. The

tribological properties of the coatings were characterized

by sliding wear tests in different environments of humid

air and in dry nitrogen. Microstructural assessment was

performed using scanning electron microscopy and atomic

force microscopy (AFM). DLC coatings produced the

lowest friction coefficient in dry nitrogen and in humid air,

demonstrating their versatility. The coefficient of friction

can be attributed to the oxidation of MoS2 at the wear

track to form MoOx that is known to cause an increase in

the friction coefficient.

In this study, the performance of the coatings

TiN, CrN and WC/C applied on steel substrates that were

subjected to sliding wear was analyzed[36]. These

materials normally exhibit an efficient performance in

applications such as coatings of cutting tools, stamping

processes, forming and plastic injection tooling where the

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contact and sliding conditions are severe. Due to this fact,

this research was conducted to characterize the materials in

relation to the wear process. The sliding wear test was

performed using a reciprocating wear test machine. All

tests were conducted in dry conditions with a room

temperature between 20 °C and 23 °C and 45% to 50%

relative humidity. It was possible to know the wear life of

these coatings and possible causes of life variations. The

load was an important factor in the variation of the wear

life results, although other factors such as surface

roughness and coating thickness were also significant.

Al 6063 based in situ composites were

manufactured from Al–10%Ti and Al–3%B master alloys

by liquid metallurgy route. Tribological properties of both

Al 6063 matrix alloy and the developed in situ composites

have been evaluated. Dry sliding friction and wear tests

were carried out using a pin on disc type machine with

steel counter disc hardened to HRC60. A load range of 10–

50 N with the sliding velocity varying from 0.209 m/s to

1.256 m/s were adopted. Results have revealed that the

developed in situ composites have lowered coefficient of

friction and wear rates when compared with Al 6063

matrix alloy under all the test conditions studied. However,

wear rates of both matrix alloy and in situ composites

increased with increase in both load and sliding

velocity[37].

A procedure is developed for the study of wear of

aluminum alloys AlSi7 obtained by casting, reinforced by

TiC micro particles, before and after heat treatment.

Tribological study is realized under conditions of friction

on counter body with fixed abrasive. Experimental results

were obtained for mass wear, wear rate, wear intensity and

wear-resistance of the alloys with different wt. % of micro

particles [38].

S. Srivastava et al [39]studied a modified impeller

mixing coupled with chill casting technique was used for

the preparation of Al-Fe composite. The electrolytic grade

iron powder of 300mesh size was dispersed in the melt of

commercially pure aluminum. The ductility showed the

adverse effect with increase of the iron content in the

matrix. The results from microstructure showed the

presence of second phase particles at the grain boundaries

of aluminum-rich phase as well as within the grain itself

which was confirmed by EPMA line as well as XRD

analysis.

The wear parameters studied are sliding speed,

applied load, time and percentage of Ferro-manganese

additions. The experimental data were taken in a controlled

way. Scanning electron microscope was used to examine

the morphology of the samples [40]. The results from

linear regression equation and analysis of variances shows

that manganese additions, load and speed variable are

more pronounced on the wear behavior of the NF Grey (8)

C.I.

Manu Varghese et al.[41] found that the coconut

oil enhanced by addition of copper oxide nanoparticles

reduced the friction very effectively. All the review of the

literature done left the scope for the authors to study the

impact of chemically modified rapeseed oil as lubricant for

the journal bearing. The present study is intended to bridge

this gap in the investigation on the behavior of chemically

modified rapeseed oil with Nano copper oxide as anti‐wear

additives in engine lubricant compound with synthetic

lubricant on the tribological characteristics of journal

bearing material.

The service life and the reliability of contact

mechanical seal are directly affected by the wear of seal

pairs (rotor vs. stator), especially under the cryogenic

environment in liquid rocket engine turbo pumps. Because

of the lower friction and wear rate, amorphous carbon (a-

C) coatings are the promising protective coatings of the

seal pairs for contact mechanical seal[42]. The tribological

performances of the specimen were tested under three

sealed fluid conditions (air, water and liquid nitrogen). The

results show that the coatings could endure the cryogenic

temperature while the friction coefficients decrease with

the increased contact load.

M.A. Chowdhury et al.[43] were examined the

coefficient of friction for different material pairs and found

that the frictional coefficient differs with rubbing duration,

normal load and sliding velocity.

This chapter examines three different problems

involving friction and wear[44]. The first case study

involves most of the factors that affect friction and wear: it

is that of a round shaft or journal rotating in a cylindrical

bearing. This type of journal bearing is common in all

types of rotating or reciprocating machinery: the

crankshaft bearings of an automobile are good examples.

Furthermore, it includes several advantages of possessing a

relatively soft bearing material. The second case study is

quite different: it involves the frictional properties of ice in

the design of skis and sledge runners. The third case study

is an introduction to some of the frictional properties of

polymers—that is, the selection of rubbers for anti-skid

tires.

M.A. Chowdhury et al.[45] found that the

frictional coefficient increases with a duration of rubbing

and decreases with increase in normal load.

Alves et al.[46] were studied the development of

vegetable based lubricants and the tribological behavior of

nanoparticle additives in an oil base. The results showed

that the addition of nanoparticles to conventional lubricant,

the tribological properties can be improved, the friction

and wear can be reduced due to formation of tribo film on

the worn surface. The lubricants developed from modified

vegetable oil can replace mineral oil, improving the

tribological and environmental characteristics.

It will be seen that the classical terms used to

describe the optimal properties for these alloys are mostly

qualitative[47]. To illustrate the former points, two sets of

experimental results will be summarized in the text. The

first set relates to an extensive study of classical Al–Sn

alloys, illustrating that even in this system, improvement is

still possible. The second one describes an attempt to use

258

the concept of compatibility, as described by Rabinowicz,

to define a new formulation for copper based triboalloys,

in the form of the Cu–Mg–Sn system. These examples,

together with the general principles derived from modern

literature, indicate that there is no theoretical or practical

reason why journal bearing alloys should be limited to the

existing classes.

Arumugam et al[48]were examined the

formulating environmental‐friendly lubricant with good

oxidative stability and improved cold flow behavior.

Rapeseed oil was chemically modified via, peroxidation,

hydroxylation followed by esterification process. The

results shown that the friction and wear characteristics of

diesel engine liner–piston ring combination using

diesel‐contaminated chemically modified rapeseed oil

bio‐lubricant and diesel‐ contaminated commercial

synthetic lubricant (SAE20W40) in a high frequency

reciprocating tribometer test rig.

Arumugam et al.[49] studied comparative of the

tribological properties of chemically modified rapeseed oil

with and without Nano‐ and micro scale titanium dioxide

(TiO2) particles and investigated the influence of TiO2

particles to reduce the friction and wear in chemically

modified rapeseed oil. The results showed that the TiO2

nanoparticles exhibited good friction reduction and

anti‐wear properties compared with the micro scale TiO2

and without TiO2 additives to chemically modified

rapeseed oil.

In the present work friction and wear of

polyimides reinforced by carbon, glass and aramid fibers

were studied and comparatively evaluated under dry

sliding against sandpaper and steel rig as well as under

three-body abrasive conditions[50]. The worn surfaces of

the composites were examined by scanning electron

microscopy to reveal mechanisms of materials damage. It

was proven that reinforcements affect tribological

properties of the polyimide composites to a great extent.

The best performance under tests conditions was shown by

inorganic fibers reinforced composites due to the effective

sharing of the load between surfaces in contact.

Friction and wear behavior of Al–Sn–Si alloy

with MoS2 layer under lubricated condition was

investigated by a reciprocating friction tester[51]. It

became clear that the Al–Sn–Si alloy with MoS2 layer

showed about 70% lower friction and about 1/10 lower

wear depth compared to the Al–Sn–Si alloy. The worn

surfaces of the Al–Sn–Si alloy with MoS2 layer were

observed and analyzed by a SEM, a TEM and an EDX. It

indicated that the sliding surface of the counter face had

larger area of Mo than the area of Al which was transferred

from the Al–Sn–Si alloy with MoS2layer by sliding,

resulting in low friction and high wear resistance.

Within this work, the lubrication of journal

bearings is investigated in detail starting from an extensive

thermo-elastohydrodynamic (TEHD) simulation, which

yields important insights into the thermodynamical

behavior of journal bearings[52]. From these results a

powerful isothermal elastohydrodynamic (EHD)

simulation model using a simple approach to calculate

equivalent temperature is derived. The capabilities of the

presented simulation methods are compared to extensive

experimental measurements performed on a journal

bearings test-rig, which show excellent agreement.

Xiaowen Qi et al [53]studied to improve the

sliding friction and wear properties of the fabric self-

lubricating liner for journal bearings, conventional and

reinforced liners were prepared to investigate the influence

of weft density on the friction and wear properties of the

liner under heavy load conditions using the self-lubricating

liner performance assessment tester. The tribological

results showed that the weft density significantly affects

the tribological properties of the fabric self-lubricating

liner under heavy load conditions.

Friction surfacing was performed to produce

multi-layer coatings of AISI 1024, AISI 1045 and AISI

H13 over mild steel substrates where a continuous joining

was achieved between adjacent layers and between the

clad and the substrate[54]. Microscopic and hardness

characterization revealed the presence of bainitic and

martensitic microstructures which influenced the hardness

of the coatings. The study aimed to determine which

material combination was more wear-resistant. The

analysis suggested that AISI 1024 presents the least wear,

both in terms of friction coefficient and wear rate.

Pin-on-disc is widely used to evaluate tribological

properties of thin films. However, the results are often

present without standard uncertainties; moreover, in many

cases the standard uncertainty is replaced by standard

deviation, which is a strong underestimation of real

uncertainty. In this study we have followed ISO and NIST

guidelines to investigate the possible sources of

uncertainties related to friction and wear rate measurement

and to apply them on two selected coating systems – TiN

and DLC. We show that influence of operator is a

significant contribution to the uncertainty of the wear rate,

particularly in the case of very low wear of DLC coatings

[55].

V. SUMMARY OF LITERATURE

SURVEY

The summery researches done by experts in the

area of wear and friction in journal bearings have been

presented in Table1 which Carries the Author name, year

and investigated problem types.

Table 1: Summary of the developments in wear and friction in journal bearings on literature survey.

Sr. no. Author Name (Year) Investigated Problem Type

259

5 K.H. Habig, E. Broszeit et al (1981) Friction and wear tests on metallic bearing materials for oil-

lubricated bearings.

6 Shyam Bahadur et al (2000) The development of transfer layers and their role in polymer

tribology

7 M. Voong, A. Neville et al (2003) The compatibility of crankcase lubricant‐material combinations

in internal combustion engines.

8 Yuji Yamamoto et al (2004) Friction and wear of water lubricated PEEK and PPS sliding

contacts

9 S. Das, S.K. Biswas (2004) Boundary lubricated tribology of an Aluminium–silicon alloy

sliding against steel.

10 Ertugrul Durak et al (2004) A study on friction behaviour of rapeseed oil as an

environmentally friendly additive in lubricating oil.

11 Klaus Friedrich et al (2005) Effects of various fillers on the sliding wear of polymer

composites.

12 Gwidon W. Stachowiak et al (2006) Wear of Non-Metallic Materials

13 H. Unal et al (2006) An approach to friction and wear properties of

polytetraflouroethylene composite.

14 A. Hernandez Battez et al (2007) Wear prevention behaviour of nanoparticle suspension under

extreme pressure conditions.

15 Y.Y. Wu et al (2007) Experimental analysis of tribological properties of lubricating

oils with nanoparticle additives

16 Tong-Sheng Li et al (2007) Tribological behaviours of several polymer–polymer sliding

combinations under dry friction and oil-lubricated conditions

17 Enver Atik et al (2007) Determination of friction coefficient in journal bearings.

18 E. Feyzullahoglu et al (2008) Tribological behaviour of tin‐based materials and brass in oil

lubricated conditions.

19 Yu H, Xu Y et al (2008) Tribological properties and lubricating mechanisms of Cu

nanoparticles in lubricant.

20 H.L. Yu et al (2008) Characterization and Nano‐ mechanical properties of tribofilms

using Cu nanoparticles as additives.

21 Padelis G. Nikolakopoulos et al (2008) A study of friction in worn misaligned journal bearings under

severe hydrodynamic lubrication.

22 Erol Feyzullahoglu et al (2008) The tribological behaviour of different engineering plastics

under dry friction conditions.

23 J.D. Bressana et al (2008) Influence of hardness on the wear resistance of 17-4 PH

stainless steel evaluated by the pin-on-disc testing.

24 G. Zhanga et al (2008) Effects of sliding velocity and applied load on the tribological

mechanism of amorphous poly-ether–ether–ketone (PEEK).

25 Hernandez Battez et al (2008) CuO, ZrO2 and ZnO nanoparticles as antiwear additive in oil

lubricants.

26 Hakan Cetinel et al (2008) Tribological behaviour of Cr2O3 coatings as bearing materials.

27 Mustafa Nursoy et al (2008) Wear behaviour of a crankshaft journal bearing manufactured

by powder spraying.

28 Y. Choi et al (2009) Tribological behaviour of copper nanoparticles as additives in

oil.

29 Boncheol Ku et al (2010)

Comparison of tribological characteristics between aluminium

alloys and polytetrafluoroethylene composites journal bearings

under mineral oil lubrication.

30 S.Y. Jiang et al (2010) Tribological behaviour of plasma‐spray TiO2 coating against

metallic bearing materials under oil lubrication.

31 T. Ramesh Kumar et al (2010) Investigation on the Mechanical and Tribological Properties of

Aluminium‐ Tin Based Plain Bearing Material

32 Erik D. Szakaly et al (2010) The effect of process and material parameters on the coefficient

of friction in the flat-die test.

260

33 S. Reina et al (2010) Determining the coefficient of friction between solids without

sliding.

34 Erol Feyzullahoglu et al (2010) The wear of Aluminium‐based journal bearing materials under

lubrication.

35 A.J. Gant et al (2011) The wear and friction behaviour of engineering coatings in

ambient air and dry nitrogen.

36 E.E. Vera et al (2011) A study of the wear performance of TiN, CrN and WC/C

coatings on different steel substrates.

37 C.S. Ramesh et al (2011) Friction and wear behaviour of cast Al 6063 based in situ metal

matrix composites.

38 M. Kandeva et al (2011) Wear‐resistance of Aluminium Matrix Micro composite

Materials.

39 S. Srivastava et al (2011) Study of Wear and Friction of Al‐Fe Metal Matrix Composite

Produced by Liquid Metallurgical Method.

40 J.O. Agunsoye et al (2012) Effect of Manganese Additions and Wear Parameter on the

Tribological Behaviour of NF Grey (8) Cast Iron.

41 Manu Varghese Thottackkad et al

(2012)

Experimental Evaluation on the Tribological Properties of

Coconut Oil by the Addition of CuO Nanoparticles.

42 Jianlei Wang et al (2012)

Experimental study on friction and wear behaviour of

amorphous carbon coatings for mechanical seals in cryogenic

environment.

43 M.A. Chowdhury et al (2012) Friction Coefficient of Different Material Pairs under Different

Normal Loads and Sliding Velocities.

44 Michael F. Ashby et al (2012) Case Studies in Friction and Wear.

45 M.A. Chowdhury et al (2012) Experimental Investigation on Friction and Wear Properties of

Different Steel Materials.

46 S.M. Alves et al (2013) Tribological behaviour of vegetable oil‐based lubricants with

nanoparticles of oxides in boundary lubrication conditions.

47 A.E. Bravo et al (2013) Towards new formulations for journal bearing alloys.

48 S. Arumugam et al (2013)

Synthesis and characterization of rapeseed oil bio‐lubricant ‐ its

effect on wear and frictional behavior of piston ring ‐ cylinder

liner combination.

49 S. Arumugam et al (2013) Preliminary Study of Nano‐ and micro scale TiO2 additives on

tribological behavior of chemically modified rapeseed Oil

50 Gai Zhao et al (2013) Friction and wear of fiber reinforced polyimide composites.

51 T. Miyajima et al (2013)

Friction and wear properties of lead-free aluminum alloy

bearing material with molybdenum disulphide layer by a

reciprocating test.

52 H. Allmaier et al (2013) Simulating Friction Power Losses in Automotive Journal

Bearings.

53 Xiaowen Qi et al (2014)

Effects of weft density on the friction and wear Properties of

self-lubricating fabric Liners for journal Bearings under heavy

load conditions.

54 D.Pereira et al (2014) Wear behavior of Steel Coatings Produced by Friction

Surfacing.

55 R. Novak et al (2014) Tribological analysis of thin films by pin-on-disc: Evaluation of

friction and wear measurement uncertainty.

VI. DISCUSSION

Wear depends upon the cohesion of transfer film, adhesion

of transfer film to the counter face, and the protection of

rubbing polymer surface from metal asperities by transfer

film.

In a completely ferrous‐based system fully formulated

lubricants are effective in reducing wear and friction.

261

Under boundary lubricating conditions, PEEK reinforced

with glass fiber was little improved in friction and wear

characteristics, since both PEEK and glass fiber had poor

resistance to wear in water.

Ceramics are resistant to high temperatures and often have

a good wear resistance but their applications are limited by

poor friction coefficients, especially in unlubricated

applications.

Friction and wear experiments were run under ambient

conditions in a pin-on-disc arrangement. High friction coefficient and high wear have been

observed in dry test conditions and the lubricated

conditions have low friction coefficient and low wear have

been observed.

Average friction coefficient of raw oil and Nano oil under

a load of 3000 N is decreased by 44 % and 39 %

respectively.

The friction and wear behaviors of bearings are affected by

speed, load, and temperature and working time.

In acid environment, the amount of wear loss is less than

that of in dry condition and applied load level is more

effective in dry condition. The friction and wear value of aluminum alloy bearings is

less than that of pure aluminum bearing.

The load was an important factor in the variation of the

wear life results, although other factors such as surface

roughness and coating thickness were also significant.

The friction and wear behavior of the alloys have changed

according to the sliding conditions. The frictional coefficient increases with a duration of

rubbing and decreases with increase in normal load.

The addition of nanoparticles to conventional lubricant, the

tribological properties can be improved, the friction and

wear can be reduced due to formation of tribo film on the

worn surface. The TiO2 nanoparticles exhibited good friction reduction

and anti‐wear properties compared with the micro scale

TiO2 and without TiO2 additives to chemically modified

rapeseed oil.

The capabilities of the presented simulation methods are

compared to extensive experimental measurements

performed on a journal bearings test-rig, which show

excellent agreement.

Friction surfacing was performed to produce multi-layer

coatings of AISI 1024, AISI 1045 and AISI H13 over mild

steel substrates where a continuous joining was achieved

between adjacent layers and between the clad and the

substrate.

VII. CONCLUSION

Based on the literature review, it is concluded that

wear and friction is very important criteria for the selection

of material of journal bearings and coatings of bearing.

Selection of material is done by selecting the parameters

like rate of wear, coefficient of friction, duration of use

and conditions in which journal bearing is used. Wear and

friction can be observed in dry and lubricated conditions

which is affected by speed, load, and temperature and

working time.

REFERENCES

[1]H.P. Jost, Tribology - origin and future, Wear, 136,

1989.

[2]I.M. Hutchings, Tribology - friction and wear of

engineering materials, Edward Arnold, 1992.

[3]Bharat Bhushan; Introduction to Tribology; John Wiley,

2001.

[4]Bharat Bhushan, Balkishan K. Gupta; Technology &

Engineering;McGraw-Hill, 1991.

[5]K.H. Habig, E. Broszeit, A.W.J. de Gee; Friction and

wear tests on metallic bearing materials for oil-lubricated

bearings; Wear, Volume 69, Issue 1, 1 June 1981, Pages

43-54

[6]Shyam Bahadur, The development of transfer layers

and their role in polymer tribology, Wear 245 (2000) 92–

99.

[7]M. Voong, A. Neville, R. Castle: The compatibility of

crankcase lubricant‐material combinations in internal

combustion engines, Tribology Letters, Vol. 15, No. 4, pp.

431–441, 2003.

[8]Yuji Yamamoto, Masaaki Hashimoto, Friction and wear

of water lubricated PEEK and PPS sliding contacts.

Composites with carbon or glass fiber, Wear 257 (2004)

181–189.

[9]S. Das, S.K. Biswas: Boundary lubricated tribology of

an aluminum–silicon alloy sliding against steel. Tribology

Letters, Vol. 17, No. 3, pp. 623– 628, 2004.

[10] Ertugrul Durak; A study on friction behavior of

rapeseed oil as an environmentally friendly additive in

lubricating oil, Industrial Lubrication and Tribology, Vol.

56, No. 1, pp. 23–37, 2004.

[11]Klaus Friedrich, Zhong Zhang, Alois K. Schlarb,

Effects of various fillers on the sliding wear of polymer

composites, Composites Science and Technology 65

(2005) 2329–2343.

[12]Gwidon W. Stachowiak, Andrew W. Batchelor; Wear

of Non-Metallic Materials; Engineering Tribology (Third

Edition), 2006, Pages 651-704

[13] H. Unal, U.sen, A Mimaroglu, 2006, ―An approach to

friction and wear properties of polytetraflouroethylene

composite‖, Materials and Design 27 (2006) 694–699.

[14] A. Hernandez Battez, R. Gonzalez, D. Felgueroso,

J.E. Fernandez, M.R. Rocio Fernandez, M.A. Garcia, et al:

Wear prevention behavior of nanoparticle suspension

under extreme pressure conditions, Wear, Vol. 263, No.

12, pp. 1568– 1574, 2007

[15] Y.Y. Wu, W.C. Tsui, T.C. Liu: Experimental analysis

of tribological properties of lubricating oils with

262

nanoparticle additives, Wear, Vol. 262, No. 7, pp. 819–

825, 2007.

[16]Bin-Bin Jia, Tong-Sheng Li, Xu-Jun Liu, Pei-Hong

Cong; Tribological behaviors of several polymer–polymer

sliding combinations under dry friction and oil-lubricated

conditions; Wear 262 (2007) 1353–1359

[17]Bekir Sadık Unlu, Enver Atik: Determination of

friction coefficient in journal bearings, Materials and

Design, Vol. 28, No. 3, pp. 973‐977, 2007.

[18] E. Feyzullahoglu, A. Zeren, M. Zeren: Tribological

behavior of tin‐based materials and brass in oil lubricated

conditions, Materials and Design, Vol. 29, No. 3, pp. 714–

720, 2008.

[19]Yu H, Xu Y, Shi P, Xu B, Wang X, Liu Q:

Tribological properties and lubricating mechanisms of Cu

nanoparticles in lubricant, Transactions of Nonferrous

Metals Society of China, Vol. 18, No. 3, pp. 636–641,

2008.

[20] H.L. Yu, Y. Xu, P.J. Shi, B.S. Xu, X.L. Wang, Q. Liu,

H.M. Wang: Characterization and nano‐ mechanical

properties of tribofilms using Cu nanoparticles as

additives, Surface and Coatings Technology, Vol. 203, No.

1, pp. 28–34, 2008.

[21] Padelis G. Nikolakopoulos, Chris A. Papadopoulos; A

study of friction in worn misaligned journal bearings

under severe hydrodynamic lubrication; Tribology

International, Volume 41, Issue 6, June 2008, Pages 461-

472

[22] Erol Feyzullahoglu, Zehra Saffak, The tribological

behavior of different engineering plastics under dry

friction conditions, Materials and Design 29 (2008) 205–

211.

[23]J.D. Bressana,, D.P. Darosa, A. Sokolowskib, R.A.

Mesquitac, C.A. Barbosad, Influence of hardness on the

wear resistance of 17-4 PH stainless steel evaluated by the

pin-on-disc testing, Journal of materials processing

technology 2 0 5 (2008) 353–359.

[24]G. Zhanga, C. Zhanga, P. Nardinb, W.-Y. Lia, H.

Liaoa, C. Coddet , Effects of sliding velocity and applied

load on the tribological mechanism of amorphous poly-

ether–ether–ketone (PEEK), Tribology International 41

(2008) 79–86.

[25]Hernandez Battez , R. Gonzalez , J.L. Viesca , J.E.

Fernandez , J.M. Diaz Fernandez , A. Machadoc, R.

Choud, J. Riba , CuO, ZrO2 and ZnO nanoparticles as

antiwear additive in oil lubricants, Wear 265 (2008) 422–

428.

[26]Hakan Cetinel, Erdal Celik, Murat I. Kusoglu;

Tribological behavior of Cr2O3 coatings as bearing

materials; Journal of Materials Processing Technology,

Volume 196, Issues 1–3, 21 January 2008, Pages 259-265

[27]Mustafa Nursoy, Cengiz Öner, İbrahim Can; Wear

behavior of a crankshaft journal bearing manufactured by

powder spraying; Materials & Design, Volume 29, Issue

10, December 2008, Pages 2047-2051

[28]Y. Choi , C. Lee , Y. Hwang , M. Park, J. Lee ,C.

Choi, M. Jung: Tribological behavior of copper

nanoparticles as additives in oil, Current Applied Physics,

Vol. 9,No. 2, pp. 124–127, 2009.

[29]Boncheol Ku, Youngdo Park, Chiun Sung, Youngchul

Han, Junghoon Park, Yujin Hwang, Jungeun Lee, Jaekeun

Lee, Hyeongseok Kim, Sungyoung Ahn and Soo Hyung

Kim: Comparison of tribological characteristics between

aluminum alloys and polytetrafluoroethylene composites

journal bearings under mineral oil lubrication, Journal of

Mechanical Science and Technology, Vol. 24, No. 8, pp.

1631‐1635, 2010.

[30] S.Y. Jiang and H J Xie: Tribological behavior of

plasma‐spray TiO2 coating against metallic bearing

materials under oil lubrication, Journal of Engineering

Tribology, Vol. 225, No.3, pp. 128‐ 138, 2010.

[31]T. Ramesh Kumar, I. Rajendran, A.D. Latha:

Investigation on the Mechanical and Tribological

Properties of Aluminium‐ Tin Based Plain Bearing

Material, Tribology in industry, Vol. 32, No. 2, pp. 4‐10,

2010.

[32]Erik D. Szakaly, John G. Lenard; The effect of process

and material parameters on the coefficient of friction in the

flat-die test; Journal of Materials Processing Technology,

Volume 210, Issues 6–7, 1 April 2010, Pages 868-876

[33]S. Reina, R.J.H. Paynter, D.A. Hills, D. Dini;

Determining the coefficient of friction between solids

without sliding; Wear, Volume 269, Issues 5–6, 19 July

2010, Pages 339-343

[34]Erol Feyzullahoglu, Nehir Sakiroglu: The wear of

aluminum‐based journal bearing materials under

lubrication, Materials and Design, Vol. 31, No. 5, pp.

2532‐2539, 2010.

[35]A.J. Gant, M.G. Gee, L.P. Orkney; The wear and

friction behavior of engineering coatings in ambient air

and dry nitrogen; Wear, Volume 271, Issues 9–10, 29 July

2011, Pages 2164-2175

[36]E.E. Vera, M. Vite, R. Lewis, E.A. Gallardo, J.R.

Laguna-Camacho; A study of the wear performance of

TiN, CrN and WC/C coatings on different steel substrates;

Wear, Volume 271, Issues 9–10, 29 July 2011, Pages

2116-2124

[37]C.S. Ramesh, Abrar Ahamed; Friction and wear

behavior of cast Al 6063 based in situ metal matrix

composites; Wear, Volume 271, Issues 9–10, 29 July

2011, Pages 1928-1939

[38] M. Kandeva, L. Vasileva, R. Rangelov, S.

Simeonova: Wear‐resistance of Aluminum Matrix Micro

composite Materials, Tribology in Industry, Vol. 33, No. 2,

pp. 57‐62, 2011.

[39] S. Srivastava, S. Mohan: Study of Wear and Friction

of Al‐Fe Metal Matrix Composite Produced by Liquid

Metallurgical Method, Tribology in Industry, Vol. 33, No.

3, pp. 128‐ 137, 2011.

[40] J.O. Agunsoye, E.F. Ochulor, S.I. Talabi, S. and

Olatunji: Effect of Manganese Additions and Wear

Parameter on the Tribological Behavior of NF Grey(8)

Cast Iron, Tribology in Industry, Vol. 34, No. 4, pp.

239‐246, 2012.

263

[41] Manu Varghese Thottackkad, Rajendrakumar

Krishnan Perikinalil and Prabhakaran Nair Kumarapillai:

Experimental Evaluation on the Tribological Properties of

Coconut Oil by the Addition of CuO Nanoparticles,

International Journal Of Precision Engineering And

Manufacturing, Vol. 13, No. 1, pp. 111‐116, 2012.

[42]Jianlei Wang, Qian Jia, Xiaoyang Yuan, Shaopeng

Wang; Experimental study on friction and wear behavior

of amorphous carbon coatings for mechanical seals in

cryogenic environment; Applied Surface Science, Volume

258, Issue 24, 1 October 2012, Pages 9531-9535

[43] M.A. Chowdhury, D.M. Nuruzzaman, A.H. Mia,

M.L. Rahaman: Friction Coefficient of Different Material

Pairs under Different Normal Loads and Sliding

Velocities, Tribology in Industry, Vol. 34, No. 1, pp.

18‐23, 2012.

[44]Michael F. Ashby, David R.H. Jones; Case Studies in

Friction and Wear; Engineering Materials 1 (Fourth

Edition), 2012, Pages 431-442.

[45]M.A. Chowdhury and D.M. Nuruzzaman:

Experimental Investigation on Friction and Wear

Properties of Different Steel Materials, Tribology in

Industry, Vol. 35, No. 1, pp. 42‐50, 2013.

[46] S.M. Alves, B.S. Barros, M.F. Trajano, K.S.B.

Ribeiro, and E. Moura: Tribological behavior of vegetable

oil‐based lubricants with nanoparticles of oxides in

boundary lubrication conditions, Tribology International,

Vol. 65, No. 1, pp. 28– 36, 2013.

[47]A.E. Bravo, H.A. Durán, V.H. Jacobo, A. Ortiz, R.

Schouwenaars; Towards new formulations for journal

bearing alloys; Wear, Volume 302, Issues 1–2, April–May

2013, Pages 1528-1535

[48] S. Arumugam, G. Sriram: Synthesis and

characterization of rapeseed oil bio‐lubricant ‐ its effect on

wear and frictional behavior of piston ring ‐ cylinder liner

combination, Journal of Engineering Tribology, Vol. 227,

No. 1, pp. 3‐15, 2013.

[49] S. Arumugam, G. Sriram: Preliminary Study of Nano‐ and micro scale TiO2 additives on tribological behavior of

chemically modified rapeseed Oil, Tribology Transactions,

Vol. 56, No. 5, pp. 797‐805, 2013.

[50]Gai Zhao, Irina Hussainova, Maksim Antonov, Qihua

Wang, Tingmei Wang; Friction and wear of fiber

reinforced polyimide composites; Wear, Volume 301,

Issues 1–2, April–May 2013, Pages 122-129

[51]T. Miyajima, Y. Tanaka, Y. Iwai, Y. Kagohara, S.

Haneda, S. Takayanagi, H. Katsuki; Friction and wear

properties of lead-free aluminum alloy bearing material

with molybdenum disulfide layer by a reciprocating test;

Tribology International, Volume 59, March 2013, Pages

17-22

[52]H. Allmaier, D.E. Sander, F.M. Reich Simulating

Friction Power Losses in Automotive Journal Bearings;

Procedia Engineering; Volume 68, 2013, Pages 49–55;

INTERNATIONAL TRIBOLOGY CONFERENCE

MALAYSIA 2013.

[53]Xiaowen Qi, Jian Ma, Zhining Jia, Yulin Yang, Haibi

Gao; Effects of weft density on the friction and wear

Properties of self-lubricating fabric Liners for journal

Bearings under heavy load conditions; Wear, In Press,

Accepted Manuscript, Available online 8 July 2014

[54]D.Pereira, J. Gandra, J. Pamies-Teixeira, R.M.

Miranda, P. Vilaça; Wear behavior of Steel Coatings

Produced by Friction Surfacing; Journal of Materials

Processing Technology, In Press, Accepted Manuscript,

Available online 1 July 2014

[55]R. Novak, T. Polcar; Tribological analysis of thin

films by pin-on-disc: Evaluation of friction and wear

measurement uncertainty; Tribology International, Volume

74, June 2014, Pages 154-163

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