4037:
and compatible and rough surfaces, in which the wear processes are much more violent. Wear plays a fundamental role in tribological studies, since it causes changes in the shape of the components used in the construction of machinery (for example). These worn parts must be replaced and this entails both a problem of an economic nature, due to the cost of replacement, and a functional problem, since if these components are not replaced in time, more serious damage could occur to the machine in its complex. This phenomenon, however, has not only negative sides, indeed, it is often used to reduce the roughness of some materials, eliminating the asperities. Erroneously we tend to imagine wear in a direct correlation with friction, in reality these two phenomena can not be easily connected. There may be conditions such that low friction can result in significant wear and vice versa. In order for this phenomenon to occur, certain implementation times are required, which may change depending on some variables, such as load, speed, lubrication and environmental conditions, and there are different wear mechanisms, which may occur simultaneously or even combined with each other:
4515:
superficial profile of the body in the study, including a comparison before and after the occurrence of the wear phenomenon. In this first analysis the possible variations of the hardness and of the superficial geometry of the material are observed. Another method of investigation is that of the radioactive tracer, used to evaluate wear at macroscopic levels. One of the two materials in contact, involved in a wear process, is marked with a radioactive tracer. In this way, the particles of this material, which will be removed, will be easily visible and accessible. Finally, to accelerate wear times, one of the best-known techniques used is that of the high pressure contact tests. In this case, to obtain the desired results it is sufficient to apply the load on a very reduced contact area.
4118:
comb over and over again, it is observed that at some point one or more teeth of the comb come off. This phenomenon can lead to the breaking of the surfaces due to mechanical or thermal causes. The first case is that described above in which a repeated load causes high contact stresses. The second case, however, is caused by the thermal expansion of the materials involved in the process. To reduce this type of wear, therefore, it is good to try to decrease both the contact forces and the thermal cycling, that is the frequency with which different temperatures intervene. For optimal results it is also good to eliminate, as much as possible, impurities between surfaces, local defects and inclusions of foreign materials in the bodies involved.
4580:
4127:
films are continually removed from the abrasive and adhesive wear mechanisms, continually recreated by pure-contaminating metal interactions. Clearly this type of wear can be reduced by trying to create an 'ad hoc' environment, free of pollutants and sensible to minimal thermal changes. Corrosive wear can also be positive in some applications. In fact, the oxides that are created, contribute to decrease the coefficient of friction between the surfaces, or, being in many cases harder than the metal to which they belong, can be used as excellent abrasives.
1232:
2943:
which allows, by means of a software support, to insert all the desired variables. Another widely used process is the ring compression test. A flat ring of the material to be studied is plastically deformed by means of a press, if the deformation is an expansion in both the inner and the outer circle, then there will be low or zero friction coefficients. Otherwise for a deformation that expands only in the inner circle there will be increasing friction coefficients.
4069:
of the adhesive wear represented in the figure. This type of wear is very problematic, since it involves high wear speeds, but at the same time it is possible to reduce adhesion by increasing surface roughness and hardness of the surfaces involved, or by inserting layers of contaminants such as oxygen, oxides, water, or oils. In conclusion, the behavior of the adhesive wear volume can be described by means of three main laws
6378:
176:
4832:(IMechE Tribology Group, IOP Tribology Group) in the UK, the German Society for Tribology (Gesellschaft fĂŒr Tribologie), the Korean Tribology Society (KTS), the Malaysian Tribology Society (MYTRIBOS), the Japanese Society of Tribologists (JAST), the Tribology Society of India (TSI), the Chinese Mechanical Engineering Society (Chinese Tribology Institute) and the International Tribology Council.
303:(Part I originally published in 1950 and Part II in 1964). Michael J. Neale was another leader in the field during the mid-to-late 1900s. He specialized in solving problems in machine design by applying his knowledge of tribology. Neale was respected as an educator with a gift for integrating theoretical work with his own practical experience to produce easy-to-understand design guides.
542:
6390:
5540:
200:. According to Leonardo, frictional resistance was the same for two different objects of the same weight but making contact over different widths and lengths. He also observed that the force needed to overcome friction doubles as weight doubles. However, Leonardo's findings remained unpublished in his notebooks.
4109:
motion (three-body abrasive wear). At application levels, the two-body wear is easily eliminated by means of an adequate surface finish, while the three-body wear can bring serious problems and must therefore be removed as much as possible by means of suitable filters, even before of a weighted machine design.
3637:
the worst, the
American oil of the Gulf Coast, the value 0. To determine the value of the intermediate oil index, the following procedure is used: two reference oils are chosen so that the oil in question has the same viscosity at 100 °C, and the following equation is used to determine the viscosity index
4108:
The abrasive wear consists of the cutting effort of hard surfaces that act on softer surfaces and can be caused either by the roughness that as tips cut off the material against which they rub (two-body abrasive wear), or from particles of hard material that interpose between two surfaces in relative
4036:
is the progressive involuntary removal of material from a surface in relative motion with another or with a fluid. We can distinguish two different types of wear: moderate wear and severe wear. The first case concerns low loads and smooth surfaces, while the second concerns significantly higher loads
2965:
What we try to achieve by means of these materials is a perfect fluid lubrication, or a lubrication such that it is possible to avoid direct contact between the surfaces in question, inserting a lubricant film between them. To do this there are two possibilities, depending on the type of application,
1955:
The layer of oxides and impurities (third body) has a fundamental tribological importance, in fact it usually contributes to reducing friction. Another fact of fundamental importance regarding oxides is that if you could clean and smooth the surface in order to obtain a pure "metal surface", what we
1782:
Rolling the wheel continuously causes imperceptible deformations of the plane and, once passed to a subsequent point, the plane returns to its initial state. In the compression phase the plane opposes the motion of the wheel, while in the decompression phase it provides a positive contribution to the
405:
By taking advantage of the new technologies for friction reduction and wear protection, energy losses due to friction and wear in vehicles, machinery and other equipment worldwide could be reduced by 40% in the long term (15 years) and 18% in the short term (8 years). On a global scale, these savings
4514:
In experimental measurements of material wear, it is often necessary to recreate fairly small wear rates and to accelerate times. The phenomena, which in reality develop after years, in the laboratory must occur after a few days. A first evaluation of the wear processes is a visual inspection of the
4135:
The rubbing wear occurs in systems subject to more or less intense vibrations, which cause relative movements between the surfaces in contact within the order of nanometers. These microscopic relative movements cause both adhesive wear, caused by the displacement itself, and abrasive wear, caused by
4126:
The corrosive wear occurs in the presence of metals that oxidize or corrode. When the pure metal surfaces come into contact with the surrounding environment, oxide films are created on their surfaces because of the contaminants present in the environment itself, such as water, oxygen or acids. These
1983:
The energy that is dissipated during the phenomenon is transformed into heat, thus increasing the temperature of the surfaces in contact. The increase in temperature also depends on the relative speed and the roughness of the material, it can be so high as to even lead to the fusion of the materials
815:
By continuously increasing the applied force, we obtain a value such that the block starts instantly to move. At this point, also taking into account the first two friction laws stated above, it is possible to define the static friction force as a force equal in modulus to the minimum force required
4068:
As known, the contact between two surfaces occurs through the interaction between asperities. If a shearing force is applied in the contact area, it may be possible to detach a small part of the weaker material, due to its adhesion to the harder surface. What is described is precisely the mechanism
3636:
In order to classify the various lubricants according to their viscosity behavior as a function of temperature, in 1929 the viscosity index (V.I.) was introduced by Dean and Davis. These assigned the best lubricant then available, namely the oil of
Pennsylvania, the viscosity index 100, and at
2942:
Then from the inclined plane we moved on to more sophisticated systems, which allow us to consider all the possible environmental conditions in which the measurement is made, such as the cross-roller machine or the pin and disk machine. Today there are digital machines such as the "Friction Tester"
2241:
The force acting between two solids in contact will not only have normal components, as implied so far, but will also have tangential components. This further complicates the description of the interactions between roughness, because due to this tangential component plastic deformation comes with a
1968:
or junctions of contact, where atom-to-atom contact takes place. The phenomenon of friction, and therefore of the dissipation of energy, is due precisely to the deformations that such regions undergo due to the load and relative movement. Plastic, elastic, or rupture deformations can be observed:
1629:
In the case of bodies capable of rolling, there is a particular type of friction, in which the sliding phenomenon, typical of dynamic friction, does not occur, but there is also a force that opposes the motion, which also excludes the case of static friction. This type of friction is called rolling
4144:
The erosion wear occurs when free particles, which can be either solid or liquid, hit a surface, causing abrasion. The mechanisms involved are of various kinds and depend on certain parameters, such as the impact angle, the particle size, the impact velocity and the material of which the particles
4117:
The fatigue wear is a type of wear that is caused by alternative loads, which cause local contact forces repeated over time, which in turn lead to deterioration of the materials involved. The most immediate example of this type of wear is that of a comb. If you slide a finger over the teeth of the
4167:
It has been verified that the harder a material is, the more it decreases. In the same way, the less two materials are mutually soluble, the more the wear tends to decrease. Finally, as regards the crystalline structure, it is possible to state that some structures are more suitable to resist the
3875:
We can therefore say, in conclusion, that an increase in temperature leads to a decrease in the viscosity of the oil. It is also useful to keep in mind that, in the same way, an increase in pressure implies an increase in viscosity. To evaluate the effects of pressure on viscosity, the following
675:
The study of friction phenomena is a predominantly empirical study and does not allow to reach precise results, but only to useful approximate conclusions. This inability to obtain a definite result is due to the extreme complexity of the phenomenon. If it is studied more closely it presents new
2961:
are used. Unlike what you might think, these are not just oils or fats, but any fluid material that is characterized by viscosity, such as air and water. Of course, some lubricants are more suitable than others, depending on the type of use they are intended for: air and water, for example, are
452:
Classical tribology covering such applications as ball bearings, gear drives, clutches, brakes, etc. was developed in the context of mechanical engineering. But in the last decades tribology expanded to qualitatively new fields of applications, in particular micro- and nanotechnology as well as
1698:, which is equal to the value of the rolling friction coefficient. The opposition to the motion is caused by the separation of the normal force and the weight force at the exact moment in which the rolling starts, so the value of the torque given by the rolling friction force is
4555:. For example, in metal-forming operations, friction increases tool wear and the power required to work a piece. This results in increased costs due to more frequent tool replacement, loss of tolerance as tool dimensions shift, and greater forces required to shape a piece.
2367:
2940:
3870:
1622:
1956:
would observe is the union of the two surfaces in contact. In fact, in the absence of thin layers of contaminants, the atoms of the metal in question, are not able to distinguish one body from another, thus going to form a single body if put in contact.
1934:
Going even deeper, it is possible to study not only the most external surface of the metal, but also the immediately more internal states, linked to the history of the metal, its composition and the manufacturing processes undergone by the latter.
2755:
The simplest and most immediate method for evaluating the friction coefficient of two surfaces is the use of an inclined plane on which a block of material is made to slide. As can be seen in the figure, the normal force of the plane is given by
1778:
What happens in detail at the microscopic level between the wheel and the supporting surface is described in Figure, where it is possible to observe what is the behavior of the reaction forces of the deformed plane acting on an immobile wheel.
1376:
Usually, the value of both coefficients does not exceed the unit and can be considered constant only within certain ranges of forces and velocities, outside of which there are extreme conditions that modify these coefficients and variables.
657:
comes from the Latin "frictionem", which means rubbing. This term is used to describe all those dissipative phenomena, capable of producing heat and of opposing the relative motion between two surfaces. There are two main types of friction:
2540:= 1 it returns to the condition in which the surfaces are directly in contact and there is no presence of a third body. Keeping in mind what has just been said, it is possible to correct the friction coefficient formula as follows:
1987:
In friction phenomena, temperature is fundamental in many areas of application. For example, a rise in temperature may result in a sharp reduction of the friction coefficient, and consequently, the effectiveness of the brakes.
991:
2433:
should also be considered, i.e., the presence of foreign materials, such as moisture, oxides or lubricants, between the two solids in contact. A coefficient c is then introduced which is able to correlate the shear strength
4840:
Tribology research is mostly empirical, which can be explained by the vast number of parameters that influence friction and wear in tribological contacts. Thus, most research fields rely heavily on the use of standardized
4272:
This coefficient makes it possible to subdivide, depending on its size, the damage suffered by various materials in different situations, passing from a modest degree of wear, through a medium, to a degree of severe wear.
716:
later found deviations from
Amontonsâ laws in some cases. In systems with significant nonuniform stress fields, Amontonsâ laws are not satisfied macroscopically because local slip occurs before the entire system slides.
1222:
2245:
402:
In total, ~23% of the world's energy consumption originates from tribological contacts. Of that, 20% is to overcome friction and 3% to remanufacture worn parts and spare equipment due to wear and wear-related.
3706:
2823:
1776:
1380:
In systems with significant nonuniform stress fields, the macroscopic static friction coefficient depends on the external pressure, system size, or shape because local slip occurs before the system slides.
476:
is used to provide a detailed assessment of relevant inputs, outputs and losses to tribological systems. Knowledge of these parameters allows tribologists to devise test procedures for tribological systems.
353:
government established several national centres to address tribological problems. Since then the term has diffused into the international community, with many specialists now identifying as "tribologists".
1090:. In this case it is necessary to take into account not only the first two laws of Amontons, but also of the law of Coulomb, so as to be able to affirm that the relationship between dynamic friction force
3789:
4270:
4136:
the particles produced in the adhesive phase, which remain trapped between the surfaces. This type of wear can be accelerated by the presence of corrosive substances and the increase in temperature.
3785:
2234:
it is possible to resort to materials which require less shear stress, but which are also very hard. In the case of lubricants, in fact, we use a substrate of material with low cutting stress
5106:
Gao, Jianping; Luedtke, W. D.; Gourdon, D.; Ruths, M.; Israelachvili, J. N.; Landman, Uzi (1 March 2004). "Frictional Forces and
Amontons' Law: From the Molecular to the Macroscopic Scale".
4532:. However, the study of tribology extends into most aspects of modern technology and any system where one material slides over another can be affected by complex tribological interactions.
3927:
2175:
1858:
4096:
An important aspect of wear is emission of wear particles into the environment which increasingly threatens human health and ecology. The first researcher who investigated this topic was
2103:
1694:
At this point the wheel is set in motion, causing a displacement at the point of application of the normal force which is now applied in front of the center of the wheel, at a distance
3519:
6191:
2616:
767:
must be applied, in this way we observe a certain resistance to the motion given by a force equal to and opposite to the applied force, which is precisely the static frictional force
3173:
1630:
friction. Now we want to observe in detail what happens to a wheel that rolls on a horizontal plane. Initially the wheel is immobile and the forces acting on it are the weight force
4680:) using technologies with minimal environmental impact. This is in contrast to traditional tribology, where the means of reducing tribological losses are not holistically evaluated.
3245:
4473:
3362:
2820:. This allows us to state that the coefficient of friction can be calculated very easily, by means of the tangent of the angle in which the block begins to slip. In fact we have
2714:
2029:
load, a deformation is observed, which, as the load increases, passes from an elastic to a plastic deformation. This phenomenon involves an enlargement of the real contact area
5424:
5032:
Jost, Peter (1966). "Lubrication (Tribology) - A report on the present position and industry's needs". Department of
Education and Science. London, UK: H. M. Stationery Office.
2519:
1133:
1088:
1043:
879:
810:
2970:
Fluidostatic lubrication (or hydrostatic in the case of mineral oils) â which consists in the insertion of lubricating material under pressure between the surfaces in contact;
2208:
765:
4425:
3872:
where, in this case, H is the viscosity at 100 °F (38 °C) of the oil with V.I. = 100 and v is the kinematic viscosity of the study oil at 210 °F (99 °C).
4595:
scales, in areas as diverse as the movement of continental plates and glaciers to the locomotion of animals and insects. Tribology research is traditionally concentrated on
2818:
2786:
2423:
1920:
1316:
5801:
dos Santos, Claudio
Teodoro; Barbosa, Cåssio; de Jesus Monteiro, Maurıcio; de Cerqueira Abud, Ibrahim; Vieira Caminha, Ieda Maria; de Mello Roesler, Carlos Rodrigo (2015).
3592:
2658:
2116:
is observed, given by the presence of adhesive bonds, which were created precisely because of the plastic deformations, and therefore the frictional force will be given by
1660:
6255:
2027:
1948:
Hardened layer â has a crystalline structure of greater hardness than the inner layers, thanks to the rapid cooling to which they are subjected in the working processes;
1689:
1345:
908:
1371:
913:
4220:
4197:
3974:
2746:
2472:
1976:
Elastic deformations â deformations in which the energy expended in the compression phase is almost entirely recovered in the decompression phase (elastic hysteresis);
3994:
2387:
2177:
At this point, since the coefficient of friction is the ratio between the intensity of the frictional force and that of the applied load, it is possible to state that
4176:
To provide an assessment of the damage caused by wear, we use a dimensionless coefficient called wear rate, given by the ratio between the height change of the body
4504:
3539:
3323:
3296:
3120:
3077:
3047:
3020:
2054:
3947:
3559:
3382:
3193:
2232:
1882:
1257:
834:
1945:
Machined layer â layer which may also have inclusions of foreign material and which derives from the processing processes to which the metal has been subjected;
1786:
The force of rolling friction depends, therefore, on the small deformations suffered by the supporting surface and by the wheel itself, and can be expressed as
1277:
307:, which he first edited in 1973 and updated in 1995, is still used around the world and forms the basis of numerous training courses for engineering designers.
1146:
3619:
Temperature and pressure are two fundamental factors to evaluate when choosing a lubricant instead of another. Consider the effects of temperature initially.
2973:
Fluid fluid lubrication (or hydrodynamics) â which consists in exploiting the relative motion between the surfaces to make the lubricating material penetrate.
5259:
VortrĂ€ge ĂŒber die
Geschichte der technischen Mechanik und theoretischen Maschinenlehre und der damit im Zusammenhang stehenden mathematischen Wissenschaften
6184:
4661:
in biological systems. The field is gaining importance as human lifetime expectancy increases. Human hip and knee joints are typical biotribology systems.
3129:, necessary to cause a rolling motion in a fluid contained between two plates, is proportional to the area of the two surfaces and to the speed gradient:
2988:
The viscosity is the equivalent of friction in fluids, it describes, in fact, the ability of fluids to resist the forces that cause a change in shape.
3640:
2962:
readily available, but the former can only be used under limited load and speed conditions, while the second can contribute to the wear of materials.
1701:
4562:
and power requirements. It is also necessary to know the effects of manufacturing, all manufacturing methods leave a unique system fingerprint (i.e.
4794:(phenomenon of vanishing friction) have sparked due to increasing demand for energy savings. Furthermore, the development of new materials, such as
6075:
Dienwiebel, Martin; Verhoeven, Gertjan S.; Pradeep, Namboodiri; Frenken, Joost W. M.; Heimberg, Jennifer A.; Zandbergen, Henny W. (24 March 2004).
1951:
Outer layer or oxide layer â layer that is created due to chemical interaction with the metal's environment and from the deposition of impurities.
433:
375:
222:
Although not universally applicable, these simple statements hold for a surprisingly wide range of systems. These laws were further developed by
6177:
4225:
2242:
lower load than when ignoring this component. A more realistic description then of the area of each single junction that is created is given by
6134:
6059:
5987:
5946:
5907:
6245:
5271:
3725:
4603:
sectors, but this has considerably diversified. Tribology research can be loosely divided into the following fields (with some overlap):
725:
Consider a block of a certain mass m, placed in a quiet position on a horizontal plane. If you want to move the block, an external force
5006:
Theodor Reye was a polytechnician in ZĂŒrich, in 1860, but later became a professor in StraĂburg, according to Moritz (1885) p. 535.
4825:
246:
4539:
industry focused on reliability, ensuring the safe, continuous operation of machine components. Nowadays, due to an increased focus on
1000:
Once the block has been put into motion, the block experiences a friction force with a lesser intensity than the static friction force
4014:
Rotational viscometers, in which viscosity is obtained by evaluating the flow of fluid placed between two surfaces in relative motion.
1347:, depending on the type of surfaces that are involved in a mutual contact, and in any case, the condition is always valid such that:
5487:
5462:
5163:
4168:
wear of others, such as a hexagonal structure with a compact distribution, which can only deform by slipping along the base planes.
3879:
2119:
629:
2664:
depends on the elastic properties of the materials. Also for the elastic bodies the tangential force depends on the coefficient
2059:
6451:
6250:
4909:
4815:
3480:
2991:
Thanks to Newton's studies, a deeper understanding of the phenomenon has been achieved. He, in fact, introduced the concept of
4528:
Historically, tribology research concentrated on the design and effective lubrication of machine components, particularly for
2543:
6441:
6431:
4551:
have become progressively more complex and sophisticated in order to achieve this. Tribology also plays an important role in
3132:
2995:: "a flow in which the velocity changes from layer to layer". It is possible to ideally divide a fluid between two surfaces (
567:
2362:{\displaystyle {A_{i}}^{2}=\left({\frac {{\vec {W}}_{i}}{D}}\right)^{2}+\alpha \left({\frac {{\vec {F}}_{i}}{D}}\right)^{2}}
6162:
4709:
3565:
of the tube in which the fluid flows. If the
Reynolds number is relatively low then there is a laminar flow, whereas for
3201:
371:
90:
of how surfaces in contact deform. Approximately 20% of the total energy expenditure of the world is due to the impact of
2966:
the costs to address and the level of "perfection" of the lubrication desired to be achieved, there is a choice between:
2935:{\displaystyle \mu ={F_{a} \over N}={mg\sin \theta \over mg\cos \theta }={\sin \theta \over \cos \theta }=\tan \theta }
4737:
4579:
3328:
3196:
2671:
1965:
610:
281:
6394:
3718:
With the advancement of the technologies, oils with V.I. more than 100, which can not be described by the method above.
3597:
To conclude we want to underline that it is possible to divide the fluids into two types according to their viscosity:
2476:
345:
published in 1966. The report highlighted the huge cost of friction, wear and corrosion to the UK economy (1.1â1.4% of
5603:
5073:
4011:
Solid drop viscometers, in which viscosity is measured by calculating the velocity of a solid that moves in the fluid;
2180:
713:
704:
582:
223:
4704:. The field is becoming increasingly important as devices become smaller (e.g. micro/nanoelectromechanical systems,
1789:
215:
the force of friction acting between two sliding surfaces is proportional to the load pressing the surfaces together
6436:
6382:
5264:
Lectures on the
History of Technical Mechanics and Theoretical Machine Theory and the Related Mathematical Sciences
3865:{\displaystyle N={{\operatorname {Log} (H)-\operatorname {Log} (O_{\text{Test}})} \over {\operatorname {Log} (v)}}}
2625:
563:
3195:, which corresponds to the dynamic viscosity coefficient of the fluid, to obtain the following equation, known as
2105:
where D is the hardness of the material definable as the applied load divided by the area of the contact surface.
552:
3722:
In the case of oils with V.I. above 100 you can use a different relationship that allows you to get exact results
3604:, or fluids in which viscosity is a function of temperature and fluid pressure only and not of velocity gradient;
589:
1282:
These coefficients are dimensionless quantities, given by the ratio between the intensity of the friction force
684:
All the theories and studies on friction can be simplified into three main laws, which are valid in most cases:
6346:
5559:"Is Tribology approaching its Golden Age? Grand Challenges in Engineering Education and Tribological Research"
2719:
4721:
5419:
4944:
4775:
4713:
4612:
4018:
The first two types of viscometers are mainly used for
Newtonian fluids, while the third is very versatile.
429:
sectors are estimated to be ~10%. In the longer term, savings would be 55%, 40%, 25%, and 20%, respectively.
292:
257:. They found that coins with grit between them wore at a faster rate compared to self-mated coins. In 1860,
4008:
Capillary viscometers, in which the viscosity of the fluid is measured by sliding it into a capillary tube;
4004:
To determine the viscosity of a fluid, viscosimeters are used which can be divided into 3 main categories:
1979:
Break deformations â deformations that lead to the breaking of bumps and the creation of new contact areas.
1384:
The following table shows the values of the static and dynamic friction coefficients for common materials:
1231:
596:
6156:
5321:
4640:
418:
407:
391:
346:
273:
4432:
6314:
6260:
4761:
6076:
5651:"Systematic breakdown of Amontons' law of friction for an elastic object locally obeying Amontons' law"
4076:
The mass involved in wear is proportional to the distance traveled in the rubbing between the surfaces.
1964:
Contact between surfaces is made up of a large number of microscopic regions, in the literature called
1093:
1048:
1003:
839:
770:
226:(in 1785), who noticed that static friction force may depend on the contact time and sliding (kinetic)
140:
4771:
3384:
is high in fluids that strongly oppose the motion, while it is contained for fluids that flow easily.
728:
578:
494:
are thin films that form on tribologically stressed surfaces. They play an important role in reducing
382:
attempted to quantify their impact worldwide. They considered the four main energy consuming sectors:
101:
This section will provide an overview of tribology, with links to many of the more specialized areas.
6088:
5750:
5672:
5612:
5376:
5333:
4986:
4861:
4829:
4529:
4391:
296:
262:
120:
5153:
3622:
There are three main causes of temperature variation that can affect the behavior of the lubricant:
2791:
2759:
2392:
1285:
6446:
6361:
6336:
6301:
6229:
6220:
6012:
4765:
4665:
3607:
3568:
1887:
288:
5291:
1239:
At this point it is possible to summarize the main properties of the static friction coefficients
6421:
6331:
6112:
6032:
5993:
5923:
Ostermeyer, Georg-Peter; Popov, Valentin L.; Shilko, Evgeny V.; Vasiljeva, Olga S., eds. (2021).
5824:
5662:
5594:
5400:
5131:
4733:
4563:
4540:
1633:
689:
208:
2430:
2003:
1665:
1321:
884:
1350:
444:
cost savings in the short term. In the long term, the reduction could be as large as 3,140 MtCO
6426:
6319:
6201:
6139:
6104:
6055:
5983:
5952:
5942:
5903:
5880:
5698:
5628:
5529:
5483:
5458:
5392:
5349:
5287:
5267:
5257:
5238:
5159:
5123:
4903:
4891:
4873:
4855:
4803:
4747:
4729:
4683:
4669:
4588:
4479:
where W / H represents the real contact area, l the length of the distance traveled and k and
4202:
4179:
4097:
3952:
2441:
218:
the force of friction is independent of the apparent area of contact between the two surfaces.
193:
87:
47:
3979:
2372:
6291:
6096:
6024:
5975:
5932:
5870:
5860:
5814:
5803:"Fretting corrosion tests on orthopedic plates and screws made of ASTM F138 stainless steel"
5781:
5688:
5680:
5620:
5570:
5519:
5433:
5384:
5341:
5228:
5195:
5115:
5088:
4779:
4701:
426:
395:
277:
234:
35:
4482:
3524:
3301:
3274:
3098:
3055:
3025:
2998:
2032:
6351:
6281:
6276:
6225:
5590:
5544:
5048:
4965: â Study of physical and chemical phenomena that occur at the interface of two phases
4962:
4956:
4864: â Mechanism to constrain relative movement to the desired motion and reduce friction
4743:
4691:
4608:
3932:
3601:
3544:
3367:
3178:
3091:
of the slab, while each immediately following layer will vary this velocity of a quantity
2217:
1867:
1242:
819:
238:
75:
5732:
Szeri A.Z. (2005) - Fluid Film Lubrication: Theory and Design, Cambridge University Press
2716:
and therefore a fairly exhaustive description of the friction coefficient can be obtained
6092:
5754:
5676:
5616:
5380:
5337:
4870: â Welding process in which joining occurs without melting or heating the interface
2618:
In conclusion, the case of elastic bodies in interaction with each other is considered.
188:
Despite the relatively recent naming of the field of tribology, quantitative studies of
6013:"Triboinformatics: machine learning algorithms and data topology methods for tribology"
5693:
5650:
4968:
4791:
4755:
1602:
1262:
603:
559:
517:
511:
350:
267:
83:
317:(2nd edition). This covers developments from prehistory, through early civilizations (
6415:
6036:
5997:
5598:
4697:
4636:
4620:
4600:
4552:
4059:
Other minor wear phenomena (wear by impact, cavitation, wear-fusion, wear-spreading).
2622:
Similarly to what we have just seen, it is possible to define an equation of the type
422:
387:
322:
310:
114:
71:
6116:
5828:
5404:
5135:
66:, which are physical systems of contacting surfaces. Subfields of tribology include
4935: â Laboratory analysis of an oil based lubricant's properties and contaminants
4932:
4926:
4867:
4799:
4725:
4646:
2992:
2110:
1045:. The friction force during relative motion is known as the dynamic friction force
258:
67:
6100:
4917: â Substance introduced to reduce friction between surfaces in mutual contact
2957:
To reduce friction between surfaces and keep wear under control, materials called
1621:
986:{\displaystyle {\left|{\vec {F}}_{s.f.}\right|}\leq \mu {\left|{\vec {N}}\right|}}
175:
5046:
Mitchell, Luke (November 2012). Ward, Jacob (ed.). "The Fiction of Nonfriction".
4385:
Instead, to express the volume of wear V it is possible to use the Holm equation
98:
in the transportation, manufacturing, power generation, and residential sectors.
6356:
6169:
4950:
4920:
4751:
4658:
2952:
541:
521:
473:
467:
379:
318:
63:
59:
51:
27:
5092:
155:
coined the word in 1966, in the eponymous report which highlighted the cost of
6326:
6215:
5979:
5937:
5924:
5875:
5865:
5848:
5786:
5769:
5524:
5507:
5200:
5183:
4983: â Damaging, gradual removal or deformation of material at solid surfaces
4974:
4938:
4842:
4544:
3996:
is a constant that describes the relationship between viscosity and pressure.
3477:
To determine what kind of flow is in the study, we observe its Reynolds number
1997:
340:
325:) and highlights the key developments up to the end of the twentieth century.
152:
147:
127:
6135:"How the Obscure Science of Rubbing Built the Past and Will Shape the Future"
5956:
5884:
5632:
5575:
5558:
5533:
5396:
5353:
5242:
5184:"The research works of Coulomb and Amontons and generalized laws of friction"
5127:
4929: â Chemical compounds that improve the lubricant performance of base oil
38:. It is highly interdisciplinary, drawing on many academic fields, including
6309:
4914:
4820:
There are now numerous national and international societies, including: the
4596:
4548:
4536:
2983:
2958:
2109:
If at this point the two surfaces are sliding between them, a resistance to
525:
491:
486:
414:
383:
254:
164:
79:
43:
6108:
6028:
5819:
5802:
5702:
5438:
5388:
4923: â The presence of a material to reduce friction between two surfaces.
4672:. In particular, green tribology aims to reduce tribological losses (e.g.,
4088:
The mass involved in wear is inversely proportional to the hardness of the
5508:"Influence of tribology on global energy consumption, costs and emissions"
362:
Despite considerable research since the Jost Report, the global impact of
6400:
4885:
4879:
4795:
4783:
4673:
4650:
4566:) which will influence the tribocontact (e.g. lubricant film formation).
4558:
The use of lubricants which minimize direct surface contact reduces tool
1942:
Crystalline structure â basic structure of the metal, bulk interior form;
1217:{\displaystyle \left|{\vec {F}}_{d.f.}\right|=k{\left|{\vec {N}}\right|}}
816:
to cause the motion of the block, and the coefficient of static friction
676:
elements, which, in turn, make the global description even more complex.
665:
Which occurs between surfaces in a fixed state, or relatively stationary.
654:
648:
495:
363:
227:
204:
197:
189:
156:
91:
23:
5925:"Multiscale Biomechanics and Tribology of Inorganic and Organic Systems"
1973:
Plastic deformations â permanent deformations of the shape of the bumps;
6341:
5539:
5233:
5216:
4897:
4687:
4686:
studies friction, wear, and lubrication of geological systems, such as
3715:
There is no information if you are outside the fixed temperature range;
570: in this section. Unsourced material may be challenged and removed.
432:
Implementing advanced tribological technologies can also reduce global
55:
39:
5684:
5624:
5345:
5119:
5266:] (in German). Vol. Teil 1. Georg Olms Verlag. p. 535.
4764:
studies tribological systems that are exposed to and affected by the
4628:
3610:, or fluids in which viscosity also depends on the velocity gradient.
5768:
Popova, Elena; Popov, Valentin L.; Kim, Dae-Eun (1 September 2018).
3629:
Local thermal factors (like for car engines or refrigeration pumps);
2429:
To obtain even more realistic considerations, the phenomenon of the
211:, with whose name they are now usually associated. They state that:
4977: â Instrument that measures friction and wear between surfaces
436:
by as much as 1,460 million tons of carbon dioxide equivalent (MtCO
5667:
4858: â Additives for lubricants to prevent metal-to-metal contact
4632:
4624:
4592:
4578:
1620:
299:
at Cambridge University. Together they wrote the seminal textbook
174:
133:
16:
Science and engineering of interacting surfaces in relative motion
5543:
Material was copied from this source, which is available under a
694:
The frictional force is directly proportional to the normal load.
4980:
4900: â Form of wear caused by adhesion between sliding surfaces
4876: â Study of the deformation of solids that touch each other
4821:
4705:
4677:
4654:
4616:
4559:
4033:
4027:
3701:{\displaystyle V.I.={{L-O_{\text{Test}}} \over {L-H}}\times 100}
3125:
From what has been said, it is possible to state that the force
1771:{\displaystyle {{\vec {M}}_{r.f.}}={\vec {b}}\times m{\vec {g}}}
499:
441:
367:
250:
242:
160:
95:
31:
6173:
5367:
Tabor, D. (1 November 1969). "Frank Philip Bowden, 1903â1968".
1938:
it is possible to divide the metal into four different layers:
410:
annually and 8.7% of total energy consumption in the long term.
230:
may depend on sliding velocity, normal force and contact area.
4082:
The mass involved in wear is proportional to the applied load.
709:
Dynamic friction is independent of the relative sliding speed.
535:
287:
Other pioneers of tribology research are Australian physicist
5849:"How tribology has been helping us to advance and to survive"
4953: â Instrument used to measure the hardness of a material
2210:
thus relating to the two material properties: shear strength
138:
118:
1388:
Table of static and dynamic friction coefficients most used
78:. It is also related to other areas such as the coupling of
4724:
aims to model the behavior of tribological systems through
4607:
Classical tribology is concerned with friction and wear in
2528:
By studying the behavior at the limits it will be that for
280:
which describes sliding wear and is based on the theory of
249:, they used a simple reciprocating machine to evaluate the
5601:; Hafner, E.M. (1965). "The Feynman Lectures on Physics".
5324:(1 August 1953). "Contact and Rubbing of Flat Surfaces".
4265:{\displaystyle T_{\text{wear}}={\delta h \over \Delta l}}
3976:
is the viscosity coefficient at atmospheric pressure and
1996:
The adhesion theory states that in the case of spherical
5158:(Second ed.). Professional Engineering Publishing.
4959: â Tribological systems for spacecraft applications
4746:
studies tribological systems that can operate under the
3251:
of layer in layer and then the condition occurs so that
2214:
and hardness. To obtain low value friction coefficients
700:
Friction is independent of the apparent area of contact.
413:
The largest short term energy savings are envisioned in
5296:
Der Civilingenieur - Zeitschrift fĂŒr das Ingenieurwesen
4971: â Material degradation due to corrosion and wear.
4845:
and test procedures as well component-level test rigs.
3175:
At this point we can introduce a proportional constant
3095:, up to the layer in contact with the immobile surface
179:
Tribological experiments suggested by Leonardo da Vinci
5545:
Creative Commons Attribution 4.0 International License
4894: â Lubricant additive to reduce friction and wear
1890:
378:
are still considerable. In 2017, Kenneth Holmberg and
6011:
Hasan, Md Syam; Nosonovsky, Michael (24 March 2022).
5770:"60 years of Rabinowicz' criterion for adhesive wear"
4485:
4435:
4394:
4228:
4205:
4182:
3982:
3955:
3935:
3882:
3792:
3780:{\displaystyle V.I.={{10^{N-1}} \over {0.00715}}+100}
3728:
3643:
3571:
3547:
3527:
3483:
3370:
3331:
3304:
3277:
3204:
3181:
3135:
3101:
3058:
3028:
3001:
2826:
2794:
2762:
2722:
2674:
2628:
2546:
2479:
2444:
2395:
2375:
2248:
2220:
2183:
2122:
2062:
2035:
2006:
1870:
1792:
1704:
1668:
1636:
1353:
1324:
1288:
1265:
1245:
1149:
1096:
1051:
1006:
916:
887:
842:
822:
773:
731:
5506:
Holmberg, Kenneth; Erdemir, Ali (1 September 2017).
5425:
Biographical Memoirs of Fellows of the Royal Society
5369:
Biographical Memoirs of Fellows of the Royal Society
4758:
that can withstand extreme temperature fluctuations.
4583:
Open system tribology - wheel-rail contact in winter
62:. The fundamental objects of study in tribology are
6300:
6269:
6238:
6208:
4802:, allows for fundamentally new approaches to solve
4754:. In particular, this requires lubricants with low
4712:), and research has been aided by the invention of
3632:
Energy dissipation due to rubbing between surfaces.
3615:
Viscosity as a function of temperature and pressure
313:surveyed the history of tribology in his 1997 book
5842:
5840:
5838:
5182:Popova, Elena; Popov, Valentin L. (30 June 2015).
4498:
4467:
4419:
4264:
4214:
4191:
3988:
3968:
3941:
3921:
3864:
3779:
3700:
3586:
3553:
3533:
3521:This is a constant that depends on the fluid mass
3513:
3388:Table of viscosity coefficients Ό for some fluids
3376:
3356:
3325:, and then we can simplify the equation by writing
3317:
3290:
3239:
3187:
3167:
3114:
3071:
3041:
3014:
2934:
2812:
2780:
2740:
2708:
2652:
2610:
2513:
2466:
2438:of the pure "material" and that of the third body
2417:
2381:
2361:
2226:
2202:
2169:
2097:
2048:
2021:
1914:
1876:
1852:
1770:
1691:given by the response to the weight of the floor.
1683:
1654:
1365:
1339:
1310:
1271:
1251:
1216:
1127:
1082:
1037:
985:
902:
873:
828:
804:
759:
241:carried out the first reliable test on frictional
5457:. Oxford Classic Texts in the Physical Sciences.
5420:"David Tabor. 23 October 1913 â 26 November 2005"
4822:Society of Tribologists and Lubrication Engineers
671:Which occurs between surfaces in relative motion.
5501:
5499:
5147:
5145:
4906: â Italian Renaissance polymath (1452â1519)
4153:Among the main factors influencing wear we find
1864:in relation to the sliding friction coefficient
22:is the science and engineering of understanding
5067:
5065:
5063:
5041:
5039:
4941: â British mechanical engineer (1921â2016)
3712:For mixtures of oils the results are not exact;
524:contacts is a non-linear function of lubricant
34:phenomena for interacting surfaces in relative
5644:
5642:
4639:) as well as manufacturing processes (such as
3922:{\displaystyle \mu =\mu _{0}\exp {(\alpha p)}}
2170:{\displaystyle {\vec {F}}_{a}=A_{r}{\vec {t}}}
1853:{\displaystyle |{\vec {F}}_{r}|=b|{\vec {N}}|}
6185:
5974:. Green Energy and Technology. SpringerLink.
5970:Nosonovsky, Michael; Bhushan, Bharat (2012).
5177:
5175:
8:
6143:. Archived from the original on 8 April 2020
5217:"Wear resistance of gold alloys for coinage"
2056:, which for this reason can be expressed as:
5453:Bowden, Frank Philip; Tabor, David (2001).
5294:[On the theory of pivot friction].
4728:simulations, combining disciplines such as
4668:of tribological systems along their entire
4547:has become increasingly important and thus
2000:in contact with each other, subjected to a
448:and the cost savings 970,000 million Euros.
131:, "I rub" in classic Greek, and the suffix
6192:
6178:
6170:
6050:Erdemir, Ali; Martin, Jean Michel (2007).
5847:Stachowiak, Gwidon W. (1 September 2017).
5649:Otsuki, M.; Matsukawa, H. (2 April 2013).
5027:
5025:
5023:
5021:
2098:{\displaystyle A_{r}={{\vec {W}} \over D}}
836:as the ratio of the static friction force
196:first noted the two fundamental 'laws' of
5936:
5929:Springer Tracts in Mechanical Engineering
5874:
5864:
5818:
5785:
5692:
5666:
5574:
5523:
5437:
5232:
5199:
5074:"Leonardo da Vinci's studies of friction"
4882: â Wear or damage on loaded surfaces
4535:Traditionally, tribology research in the
4490:
4484:
4452:
4446:
4434:
4404:
4393:
4242:
4233:
4227:
4204:
4181:
3981:
3960:
3954:
3949:is the pressure viscosity coefficient p,
3934:
3905:
3893:
3881:
3843:
3833:
3801:
3799:
3791:
3764:
3751:
3746:
3744:
3727:
3679:
3672:
3661:
3659:
3642:
3570:
3546:
3526:
3514:{\displaystyle Re={{\rho Lv} \over \mu }}
3495:
3493:
3482:
3369:
3344:
3330:
3309:
3303:
3282:
3276:
3217:
3203:
3180:
3145:
3134:
3106:
3100:
3063:
3057:
3033:
3027:
3006:
3000:
2894:
2853:
2839:
2833:
2825:
2793:
2788:, while the frictional force is equal to
2761:
2721:
2688:
2677:
2676:
2673:
2639:
2638:
2627:
2595:
2591:
2578:
2553:
2545:
2496:
2478:
2449:
2443:
2409:
2398:
2397:
2394:
2374:
2353:
2338:
2327:
2326:
2323:
2306:
2291:
2280:
2279:
2276:
2262:
2255:
2250:
2247:
2219:
2190:
2182:
2156:
2155:
2149:
2136:
2125:
2124:
2121:
2079:
2078:
2076:
2067:
2061:
2040:
2034:
2008:
2007:
2005:
1897:
1889:
1869:
1845:
1834:
1833:
1828:
1817:
1811:
1800:
1799:
1793:
1791:
1757:
1756:
1739:
1738:
1719:
1708:
1707:
1705:
1703:
1670:
1669:
1667:
1641:
1640:
1635:
1352:
1326:
1325:
1323:
1302:
1291:
1290:
1287:
1264:
1244:
1198:
1197:
1192:
1167:
1156:
1155:
1148:
1110:
1099:
1098:
1095:
1065:
1054:
1053:
1050:
1020:
1009:
1008:
1005:
967:
966:
961:
935:
924:
923:
917:
915:
889:
888:
886:
856:
845:
844:
841:
821:
787:
776:
775:
772:
745:
734:
733:
730:
630:Learn how and when to remove this message
528:, entrainment velocity and contact load.
421:(20%) while the potential savings in the
5745:Stachowiak G.W.; Batchelor A.W. (2005).
4275:
3386:
2611:{\displaystyle \mu ={\frac {c}{^{1/2}}}}
1386:
1230:
558:Relevant discussion may be found on the
192:can be traced as far back as 1493, when
5017:
4999:
4199:and the length of the relative sliding
3168:{\displaystyle F\propto A{dv \over dy}}
1227:Static and dynamic friction coefficient
6154:
5455:The Friction and Lubrication of Solids
4888: â Force resisting sliding motion
4506:are experimental dimensional factors.
3052:The layer in contact with the surface
1318:and the intensity of the applied load
301:The Friction and Lubrication of Solids
5900:Tribology in Manufacturing Technology
4664:Green tribology aims to minimize the
3708:This process has some disadvantages:
3271:is the distance between the surfaces
7:
6389:
5072:Hutchings, Ian M. (15 August 2016).
3247:The speed varies by the same amount
3240:{\displaystyle F=\mu A{dv \over dy}}
568:adding citations to reliable sources
6133:Bernhard, Adrienne (7 April 2020).
5563:Frontiers in Mechanical Engineering
5108:The Journal of Physical Chemistry B
4826:Institution of Mechanical Engineers
4468:{\displaystyle V=k_{a}{W \over H}l}
5807:Research on Biomedical Engineering
4700:studies tribological phenomena at
4253:
4206:
4183:
3357:{\displaystyle F=\mu A{v \over L}}
2709:{\displaystyle {\vec {F}}_{T}=cAs}
2238:, placed on a very hard material.
1860:, where it is possible to express
1135:, coefficient of dynamic friction
207:were first published (in 1699) by
14:
5716:Resnick; Halliday; Krane (2002).
5290:(1860) . Bornemann, K. R. (ed.).
5215:Chaston, J.C. (1 December 1974).
3087:, will have the same velocity as
2514:{\displaystyle t=c\cdot t_{t.b.}}
1128:{\displaystyle {\vec {F}}_{d.f.}}
1083:{\displaystyle {\vec {F}}_{d.f.}}
1038:{\displaystyle {\vec {F}}_{s.f.}}
874:{\displaystyle {\vec {F}}_{s.f.}}
805:{\displaystyle {\vec {F}}_{s.f.}}
398:. The following were concluded:
245:. In a study commissioned by the
6388:
6377:
6376:
5538:
4786:methods to tribological systems.
4748:extreme environmental conditions
3049:) of area A, in various layers.
2389:constant and a "tangent" force
2203:{\displaystyle \mu ={t \over D}}
881:. and the normal force at block
760:{\displaystyle {\vec {F}}_{out}}
540:
440:) and result in 450,000 million
5298:. Neue Folge (NF) (in German).
5292:"Zur Theorie der Zapfenreibung"
4910:List of tribology organizations
4816:List of tribology organizations
4790:Recently, intensive studies of
4587:Tribology research ranges from
4420:{\displaystyle V=k{W \over H}l}
3541:of the fluid, on its viscosity
551:needs additional citations for
3915:
3906:
3856:
3850:
3839:
3826:
3814:
3808:
3122:, which will have zero speed.
3079:, which moves with a velocity
2813:{\displaystyle mg\sin \theta }
2781:{\displaystyle mg\cos \theta }
2682:
2644:
2588:
2584:
2565:
2559:
2418:{\displaystyle {\vec {F}}_{i}}
2403:
2332:
2285:
2161:
2130:
2084:
2013:
1915:{\textstyle b={\mu v \over r}}
1846:
1839:
1829:
1818:
1805:
1794:
1762:
1744:
1713:
1675:
1646:
1331:
1311:{\displaystyle {\vec {F}}_{f}}
1296:
1235:Dynamic and static coefficient
1203:
1161:
1104:
1059:
1014:
972:
929:
894:
850:
781:
739:
203:The two fundamental 'laws' of
1:
6101:10.1103/PhysRevLett.92.126101
5720:. Vol. 1 (5th ed.).
4947: â Deformation mechanism
3587:{\displaystyle Re\simeq 2000}
2653:{\displaystyle A=K{\vec {W}}}
337:became widely used following
6077:"Superlubricity of Graphite"
5749:. Elsevier Applied Science.
4738:computational fluid dynamics
3594:the flow becomes turbulent.
374:, economic expenditure, and
151:"study of", "knowledge of".
5604:American Journal of Physics
5557:Popov, Valentin L. (2018).
4524:Transport and manufacturing
1655:{\displaystyle m{\vec {g}}}
224:Charles-Augustin de Coulomb
6468:
5482:(2nd ed.). Elsevier.
5478:Neale, Michael J. (1995).
5326:Journal of Applied Physics
5093:10.1016/j.wear.2016.04.019
4989: â Lubricant additive
4813:
4025:
2981:
2950:
2668:seen above, and it will be
2022:{\displaystyle {\vec {W}}}
1684:{\displaystyle {\vec {N}}}
1340:{\displaystyle {\vec {W}}}
903:{\displaystyle {\vec {N}}}
646:
509:
484:
465:
139:
119:
6372:
6161:: CS1 maint: unfit URL (
5980:10.1007/978-3-642-23681-5
5938:10.1007/978-3-030-60124-9
5866:10.1007/s40544-017-0173-7
5787:10.1007/s40544-018-0240-8
5525:10.1007/s40544-017-0183-5
5256:RĂŒhlmann, Moritz (1885).
5201:10.1007/s40544-015-0074-6
4362:
4327:
4300:
4053:Rubbing wear or fretting;
1470:Steelâsteel (lubricated)
1366:{\displaystyle \mu >k}
502:in tribological systems.
6347:Condensed-matter physics
5898:J. Paulo, Davim (2013).
5576:10.3389/fmech.2018.00016
4613:rolling-element bearings
4215:{\displaystyle \Delta l}
4192:{\displaystyle \Delta h}
4131:Rubbing wear or fretting
3969:{\displaystyle \mu _{0}}
3083:due to an applied force
2741:{\displaystyle \mu =cKs}
2467:{\displaystyle t_{t.b.}}
1926:being the wheel radius.
434:carbon dioxide emissions
406:would amount to 1.4% of
376:carbon dioxide emissions
6081:Physical Review Letters
5322:Archard, John Frederick
5152:Dowson, Duncan (1997).
5087:(Supplement C): 51â66.
4945:Rolling contact fatigue
4776:Artificial Intelligence
4722:Computational tribology
4714:Atomic Force Microscopy
3989:{\displaystyle \alpha }
2382:{\displaystyle \alpha }
247:Privy Council of the UK
117:root ÏÏÎčÎČ- of the verb
6452:Mechanical engineering
6029:10.1680/jsuin.22.00027
5820:10.1590/2446-4740.0710
5480:The Tribology Handbook
5439:10.1098/rsbm.2007.0031
5389:10.1098/rsbm.1969.0001
4824:(STLE) in the US, the
4584:
4500:
4469:
4421:
4266:
4216:
4193:
4149:Factors affecting wear
3990:
3970:
3943:
3923:
3866:
3781:
3702:
3588:
3555:
3535:
3515:
3378:
3358:
3319:
3292:
3241:
3189:
3169:
3116:
3073:
3043:
3016:
2936:
2814:
2782:
2742:
2710:
2654:
2612:
2515:
2468:
2425:applied to the joint.
2419:
2383:
2363:
2228:
2204:
2171:
2099:
2050:
2023:
1960:The origin of friction
1916:
1878:
1854:
1772:
1685:
1656:
1626:
1437:Scioled wood skiâsnow
1367:
1341:
1312:
1273:
1253:
1236:
1218:
1129:
1084:
1039:
987:
904:
875:
830:
806:
761:
697:Second Law of Amontons
520:shows how friction in
453:biology and medicine.
305:The Tribology Handbook
291:and British physicist
274:John Frederick Archard
180:
6442:Materials degradation
6432:Engineering mechanics
6315:Solid-state chemistry
5747:Engineering Tribology
4804:tribological problems
4774:is an application of
4762:Open system tribology
4582:
4501:
4499:{\displaystyle k_{a}}
4470:
4422:
4267:
4217:
4194:
4163:Crystalline structure
3991:
3971:
3944:
3924:
3867:
3782:
3703:
3589:
3556:
3536:
3534:{\displaystyle \rho }
3516:
3379:
3359:
3320:
3318:{\displaystyle S_{2}}
3293:
3291:{\displaystyle S_{1}}
3242:
3190:
3170:
3117:
3115:{\displaystyle S_{1}}
3074:
3072:{\displaystyle S_{2}}
3044:
3042:{\displaystyle S_{2}}
3017:
3015:{\displaystyle S_{1}}
2937:
2815:
2783:
2751:Friction measurements
2743:
2711:
2660:where, in this case,
2655:
2613:
2516:
2469:
2420:
2384:
2364:
2229:
2205:
2172:
2100:
2051:
2049:{\displaystyle A_{r}}
2024:
1917:
1879:
1855:
1773:
1686:
1662:and the normal force
1657:
1624:
1459:Steelâsteel (smooth)
1368:
1342:
1313:
1274:
1254:
1234:
1219:
1130:
1085:
1040:
988:
905:
876:
831:
807:
762:
178:
6239:Material independent
5155:History of Tribology
5056:(November 2012): 40.
4987:Zinc dithiophosphate
4830:Institute of Physics
4666:environmental impact
4483:
4433:
4392:
4226:
4203:
4180:
3980:
3953:
3942:{\displaystyle \mu }
3933:
3880:
3790:
3726:
3641:
3608:Non-Newtonian fluids
3569:
3561:and on the diameter
3554:{\displaystyle \mu }
3545:
3525:
3481:
3377:{\displaystyle \mu }
3368:
3329:
3302:
3275:
3202:
3188:{\displaystyle \mu }
3179:
3133:
3099:
3056:
3026:
2999:
2824:
2792:
2760:
2720:
2672:
2626:
2544:
2477:
2442:
2393:
2373:
2246:
2227:{\displaystyle \mu }
2218:
2181:
2120:
2060:
2033:
2004:
1888:
1877:{\displaystyle \mu }
1868:
1790:
1702:
1666:
1634:
1569:Rubberâcement (wet)
1558:Rubberâcement (dry)
1351:
1322:
1286:
1263:
1259:and the dynamic one
1252:{\displaystyle \mu }
1243:
1147:
1094:
1049:
1004:
914:
885:
840:
829:{\displaystyle \mu }
820:
771:
729:
564:improve this article
457:Fundamental concepts
349:). As a result, the
315:History of Tribology
297:Cavendish Laboratory
6362:Solid-state physics
6357:Soft-matter physics
6337:Nuclear engineering
6256:Fundamental aspects
6230:Polymer engineering
6221:Ceramic engineering
6093:2004PhRvL..92l6101D
6017:Surface Innovations
5755:2005entr.book.....W
5677:2013NatSR...3E1586O
5617:1965AmJPh..33..750F
5595:Leighton, Robert B.
5591:Feynman, Richard P.
5381:1969JGlac...8..317T
5338:1953JAP....24..981A
4766:natural environment
4475:(for abrasive wear)
4427:(for adhesive wear)
4277:
3626:Weather conditions;
3444:Blood (37 °C)
3436:Water (20 °C)
3428:Water (90 °C)
3389:
1992:The cohesion theory
1389:
289:Frank Philip Bowden
167:to the UK economy.
6332:Mining engineering
5876:20.500.11937/59306
5655:Scientific Reports
5418:Field, J. (2008).
5288:Reye, Karl Theodor
5234:10.1007/BF03215051
4734:fracture mechanics
4585:
4564:surface topography
4541:energy consumption
4496:
4465:
4417:
4276:
4262:
4212:
4189:
4000:Viscosity measures
3986:
3966:
3939:
3919:
3862:
3777:
3698:
3584:
3551:
3531:
3511:
3387:
3374:
3354:
3315:
3288:
3237:
3185:
3165:
3112:
3069:
3039:
3012:
2932:
2810:
2778:
2738:
2706:
2650:
2608:
2511:
2464:
2415:
2379:
2359:
2224:
2200:
2167:
2095:
2046:
2019:
1912:
1874:
1850:
1768:
1681:
1652:
1627:
1387:
1363:
1337:
1308:
1269:
1249:
1237:
1214:
1125:
1080:
1035:
983:
900:
871:
826:
802:
757:
372:energy consumption
209:Guillaume Amontons
181:
6437:Materials science
6409:
6408:
6320:Polymer chemistry
6302:Interdisciplinary
6202:materials science
6140:Popular Mechanics
6061:978-0-444-52772-1
5989:978-3-642-23680-8
5948:978-3-030-60123-2
5909:978-3-642-31683-8
5685:10.1038/srep01586
5625:10.1119/1.1972241
5346:10.1063/1.1721448
5120:10.1021/jp036362l
5114:(11): 3410â3425.
4904:Leonardo da Vinci
4892:Friction modifier
4874:Contact mechanics
4856:Antiwear additive
4836:Research approach
4730:contact mechanics
4702:nanoscopic scales
4460:
4412:
4383:
4382:
4260:
4236:
4160:Mutual Solubility
4098:Ernest Rabinowicz
3860:
3836:
3769:
3690:
3675:
3509:
3475:
3474:
3452:Oil (20 °C)
3352:
3235:
3163:
2918:
2889:
2848:
2685:
2647:
2606:
2406:
2347:
2335:
2300:
2288:
2198:
2164:
2133:
2093:
2087:
2016:
1910:
1842:
1808:
1765:
1747:
1716:
1678:
1649:
1614:
1613:
1399:Dynamic friction
1393:Contact surfaces
1334:
1299:
1272:{\displaystyle k}
1206:
1164:
1143:is the following:
1139:and normal force
1107:
1062:
1017:
975:
932:
897:
853:
784:
742:
640:
639:
632:
614:
263:Reye's hypothesis
194:Leonardo da Vinci
113:derives from the
88:contact mechanics
82:and tribology in
48:materials science
6459:
6392:
6391:
6380:
6379:
6292:Microelectronics
6246:Characterization
6194:
6187:
6180:
6171:
6166:
6160:
6152:
6150:
6148:
6121:
6120:
6072:
6066:
6065:
6047:
6041:
6040:
6008:
6002:
6001:
5967:
5961:
5960:
5940:
5920:
5914:
5913:
5895:
5889:
5888:
5878:
5868:
5844:
5833:
5832:
5822:
5798:
5792:
5791:
5789:
5765:
5759:
5758:
5742:
5736:
5735:
5728:
5722:
5721:
5713:
5707:
5706:
5696:
5670:
5646:
5637:
5636:
5587:
5581:
5580:
5578:
5554:
5548:
5542:
5537:
5527:
5503:
5494:
5493:
5475:
5469:
5468:
5450:
5444:
5443:
5441:
5415:
5409:
5408:
5364:
5358:
5357:
5318:
5312:
5311:
5309:
5307:
5284:
5278:
5277:
5273:978-3-48741119-4
5253:
5247:
5246:
5236:
5212:
5206:
5205:
5203:
5179:
5170:
5169:
5149:
5140:
5139:
5103:
5097:
5096:
5078:
5069:
5058:
5057:
5043:
5034:
5033:
5029:
5007:
5004:
4780:Machine Learning
4772:Triboinformatics
4609:machine elements
4510:Wear measurement
4505:
4503:
4502:
4497:
4495:
4494:
4474:
4472:
4471:
4466:
4461:
4453:
4451:
4450:
4426:
4424:
4423:
4418:
4413:
4405:
4278:
4271:
4269:
4268:
4263:
4261:
4259:
4251:
4243:
4238:
4237:
4234:
4221:
4219:
4218:
4213:
4198:
4196:
4195:
4190:
4085:Law 3 â Hardness
4073:Law 1 â Distance
3995:
3993:
3992:
3987:
3975:
3973:
3972:
3967:
3965:
3964:
3948:
3946:
3945:
3940:
3928:
3926:
3925:
3920:
3918:
3898:
3897:
3876:equation is used
3871:
3869:
3868:
3863:
3861:
3859:
3842:
3838:
3837:
3834:
3800:
3786:
3784:
3783:
3778:
3770:
3768:
3763:
3762:
3761:
3745:
3707:
3705:
3704:
3699:
3691:
3689:
3678:
3677:
3676:
3673:
3660:
3602:Newtonian fluids
3593:
3591:
3590:
3585:
3560:
3558:
3557:
3552:
3540:
3538:
3537:
3532:
3520:
3518:
3517:
3512:
3510:
3505:
3494:
3460:Oil (0 °C)
3390:
3383:
3381:
3380:
3375:
3363:
3361:
3360:
3355:
3353:
3345:
3324:
3322:
3321:
3316:
3314:
3313:
3297:
3295:
3294:
3289:
3287:
3286:
3246:
3244:
3243:
3238:
3236:
3234:
3226:
3218:
3194:
3192:
3191:
3186:
3174:
3172:
3171:
3166:
3164:
3162:
3154:
3146:
3121:
3119:
3118:
3113:
3111:
3110:
3078:
3076:
3075:
3070:
3068:
3067:
3048:
3046:
3045:
3040:
3038:
3037:
3021:
3019:
3018:
3013:
3011:
3010:
2941:
2939:
2938:
2933:
2919:
2917:
2906:
2895:
2890:
2888:
2871:
2854:
2849:
2844:
2843:
2834:
2819:
2817:
2816:
2811:
2787:
2785:
2784:
2779:
2747:
2745:
2744:
2739:
2715:
2713:
2712:
2707:
2693:
2692:
2687:
2686:
2678:
2659:
2657:
2656:
2651:
2649:
2648:
2640:
2617:
2615:
2614:
2609:
2607:
2605:
2604:
2603:
2599:
2583:
2582:
2554:
2520:
2518:
2517:
2512:
2510:
2509:
2473:
2471:
2470:
2465:
2463:
2462:
2424:
2422:
2421:
2416:
2414:
2413:
2408:
2407:
2399:
2388:
2386:
2385:
2380:
2368:
2366:
2365:
2360:
2358:
2357:
2352:
2348:
2343:
2342:
2337:
2336:
2328:
2324:
2311:
2310:
2305:
2301:
2296:
2295:
2290:
2289:
2281:
2277:
2267:
2266:
2261:
2260:
2259:
2233:
2231:
2230:
2225:
2209:
2207:
2206:
2201:
2199:
2191:
2176:
2174:
2173:
2168:
2166:
2165:
2157:
2154:
2153:
2141:
2140:
2135:
2134:
2126:
2104:
2102:
2101:
2096:
2094:
2089:
2088:
2080:
2077:
2072:
2071:
2055:
2053:
2052:
2047:
2045:
2044:
2028:
2026:
2025:
2020:
2018:
2017:
2009:
1921:
1919:
1918:
1913:
1911:
1906:
1898:
1883:
1881:
1880:
1875:
1859:
1857:
1856:
1851:
1849:
1844:
1843:
1835:
1832:
1821:
1816:
1815:
1810:
1809:
1801:
1797:
1777:
1775:
1774:
1769:
1767:
1766:
1758:
1749:
1748:
1740:
1734:
1733:
1732:
1718:
1717:
1709:
1690:
1688:
1687:
1682:
1680:
1679:
1671:
1661:
1659:
1658:
1653:
1651:
1650:
1642:
1625:rolling friction
1617:Rolling friction
1492:Steelâice (dry)
1396:Static friction
1390:
1372:
1370:
1369:
1364:
1346:
1344:
1343:
1338:
1336:
1335:
1327:
1317:
1315:
1314:
1309:
1307:
1306:
1301:
1300:
1292:
1278:
1276:
1275:
1270:
1258:
1256:
1255:
1250:
1223:
1221:
1220:
1215:
1213:
1212:
1208:
1207:
1199:
1185:
1181:
1180:
1166:
1165:
1157:
1134:
1132:
1131:
1126:
1124:
1123:
1109:
1108:
1100:
1089:
1087:
1086:
1081:
1079:
1078:
1064:
1063:
1055:
1044:
1042:
1041:
1036:
1034:
1033:
1019:
1018:
1010:
996:Dynamic friction
992:
990:
989:
984:
982:
981:
977:
976:
968:
954:
953:
949:
948:
934:
933:
925:
909:
907:
906:
901:
899:
898:
890:
880:
878:
877:
872:
870:
869:
855:
854:
846:
835:
833:
832:
827:
811:
809:
808:
803:
801:
800:
786:
785:
777:
766:
764:
763:
758:
756:
755:
744:
743:
735:
680:Laws of friction
668:Dynamic friction
635:
628:
624:
621:
615:
613:
572:
544:
536:
522:fluid-lubricated
419:power generation
392:power generation
278:Archard equation
271:
235:Charles Hatchett
144:
143:
124:
123:
6467:
6466:
6462:
6461:
6460:
6458:
6457:
6456:
6412:
6411:
6410:
6405:
6368:
6352:Polymer physics
6296:
6282:Surface science
6277:Crystallography
6265:
6234:
6226:Polymer science
6204:
6198:
6153:
6146:
6144:
6132:
6129:
6124:
6074:
6073:
6069:
6062:
6049:
6048:
6044:
6023:(12): 229â242.
6010:
6009:
6005:
5990:
5972:Green Tribology
5969:
5968:
5964:
5949:
5922:
5921:
5917:
5910:
5897:
5896:
5892:
5846:
5845:
5836:
5800:
5799:
5795:
5767:
5766:
5762:
5744:
5743:
5739:
5730:
5729:
5725:
5715:
5714:
5710:
5648:
5647:
5640:
5589:
5588:
5584:
5556:
5555:
5551:
5505:
5504:
5497:
5490:
5477:
5476:
5472:
5465:
5452:
5451:
5447:
5417:
5416:
5412:
5366:
5365:
5361:
5320:
5319:
5315:
5305:
5303:
5286:
5285:
5281:
5274:
5255:
5254:
5250:
5214:
5213:
5209:
5181:
5180:
5173:
5166:
5151:
5150:
5143:
5105:
5104:
5100:
5076:
5071:
5070:
5061:
5049:Popular Science
5045:
5044:
5037:
5031:
5030:
5019:
5015:
5010:
5005:
5001:
4997:
4992:
4963:Surface science
4957:Space tribology
4851:
4838:
4818:
4812:
4744:Space tribology
4577:
4572:
4526:
4521:
4512:
4486:
4481:
4480:
4442:
4431:
4430:
4390:
4389:
4287:
4252:
4244:
4229:
4224:
4223:
4201:
4200:
4178:
4177:
4174:
4151:
4142:
4133:
4124:
4115:
4106:
4066:
4050:Corrosive wear;
4030:
4024:
4002:
3978:
3977:
3956:
3951:
3950:
3931:
3930:
3889:
3878:
3877:
3829:
3788:
3787:
3747:
3724:
3723:
3668:
3639:
3638:
3617:
3567:
3566:
3543:
3542:
3523:
3522:
3479:
3478:
3404:
3366:
3365:
3327:
3326:
3305:
3300:
3299:
3278:
3273:
3272:
3227:
3219:
3200:
3199:
3177:
3176:
3155:
3147:
3131:
3130:
3102:
3097:
3096:
3059:
3054:
3053:
3029:
3024:
3023:
3002:
2997:
2996:
2986:
2980:
2955:
2949:
2907:
2896:
2872:
2855:
2835:
2822:
2821:
2790:
2789:
2758:
2757:
2753:
2718:
2717:
2675:
2670:
2669:
2624:
2623:
2621:
2587:
2574:
2558:
2542:
2541:
2492:
2475:
2474:
2445:
2440:
2439:
2428:
2396:
2391:
2390:
2371:
2370:
2325:
2319:
2318:
2278:
2272:
2271:
2251:
2249:
2244:
2243:
2216:
2215:
2179:
2178:
2145:
2123:
2118:
2117:
2108:
2063:
2058:
2057:
2036:
2031:
2030:
2002:
2001:
1994:
1962:
1932:
1899:
1886:
1885:
1866:
1865:
1798:
1788:
1787:
1706:
1700:
1699:
1664:
1663:
1632:
1631:
1619:
1603:Synovial joints
1503:Steelâaluminum
1415:Woodâcardboard
1349:
1348:
1320:
1319:
1289:
1284:
1283:
1261:
1260:
1241:
1240:
1229:
1193:
1154:
1150:
1145:
1144:
1097:
1092:
1091:
1052:
1047:
1046:
1007:
1002:
1001:
998:
962:
922:
918:
912:
911:
883:
882:
843:
838:
837:
818:
817:
774:
769:
768:
732:
727:
726:
723:
721:Static friction
682:
662:Static friction
651:
645:
636:
625:
619:
616:
573:
571:
557:
545:
534:
514:
508:
489:
483:
472:The concept of
470:
464:
459:
447:
439:
360:
331:
329:The Jost report
265:
239:Henry Cavendish
186:
173:
107:
76:space tribology
17:
12:
11:
5:
6465:
6463:
6455:
6454:
6449:
6444:
6439:
6434:
6429:
6424:
6414:
6413:
6407:
6406:
6404:
6403:
6398:
6386:
6373:
6370:
6369:
6367:
6366:
6365:
6364:
6359:
6354:
6349:
6339:
6334:
6329:
6324:
6323:
6322:
6317:
6306:
6304:
6298:
6297:
6295:
6294:
6289:
6284:
6279:
6273:
6271:
6267:
6266:
6264:
6263:
6258:
6253:
6248:
6242:
6240:
6236:
6235:
6233:
6232:
6223:
6218:
6212:
6210:
6206:
6205:
6199:
6197:
6196:
6189:
6182:
6174:
6168:
6167:
6128:
6127:External links
6125:
6123:
6122:
6087:(12): 126101.
6067:
6060:
6052:Superlubricity
6042:
6003:
5988:
5962:
5947:
5915:
5908:
5890:
5859:(3): 233â247.
5834:
5813:(2): 169â175.
5793:
5780:(3): 341â348.
5760:
5737:
5723:
5708:
5638:
5611:(9): 750â752.
5599:Sands, Matthew
5582:
5549:
5518:(3): 263â284.
5495:
5488:
5470:
5463:
5445:
5410:
5359:
5332:(8): 981â988.
5313:
5279:
5272:
5248:
5227:(4): 108â112.
5207:
5194:(2): 183â190.
5171:
5164:
5141:
5098:
5059:
5035:
5016:
5014:
5011:
5009:
5008:
4998:
4996:
4993:
4991:
4990:
4984:
4978:
4972:
4969:Tribocorrosion
4966:
4960:
4954:
4948:
4942:
4936:
4930:
4924:
4918:
4912:
4907:
4901:
4895:
4889:
4883:
4877:
4871:
4865:
4859:
4852:
4850:
4847:
4837:
4834:
4814:Main article:
4811:
4808:
4792:superlubricity
4788:
4787:
4769:
4759:
4756:vapor pressure
4741:
4719:
4717:
4695:
4681:
4662:
4644:
4637:fluid bearings
4621:plain bearings
4576:
4573:
4571:
4568:
4525:
4522:
4520:
4517:
4511:
4508:
4493:
4489:
4477:
4476:
4464:
4459:
4456:
4449:
4445:
4441:
4438:
4428:
4416:
4411:
4408:
4403:
4400:
4397:
4381:
4380:
4377:
4373:
4372:
4369:
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4364:
4361:
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4307:
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4232:
4211:
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4188:
4185:
4173:
4170:
4165:
4164:
4161:
4158:
4150:
4147:
4141:
4138:
4132:
4129:
4123:
4122:Corrosive wear
4120:
4114:
4111:
4105:
4102:
4094:
4093:
4092:hard material.
4086:
4083:
4080:
4077:
4074:
4065:
4062:
4061:
4060:
4057:
4054:
4051:
4048:
4045:
4044:Abrasive wear;
4042:
4041:Adhesive wear;
4026:Main article:
4023:
4020:
4016:
4015:
4012:
4009:
4001:
3998:
3985:
3963:
3959:
3938:
3917:
3914:
3911:
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3807:
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3798:
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3697:
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3649:
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3583:
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3501:
3498:
3492:
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3473:
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3433:
3432:
3429:
3425:
3424:
3421:
3417:
3416:
3413:
3409:
3408:
3405:
3402:
3398:
3397:
3394:
3373:
3364:The viscosity
3351:
3348:
3343:
3340:
3337:
3334:
3312:
3308:
3285:
3281:
3233:
3230:
3225:
3222:
3216:
3213:
3210:
3207:
3184:
3161:
3158:
3153:
3150:
3144:
3141:
3138:
3109:
3105:
3066:
3062:
3036:
3032:
3009:
3005:
2982:Main article:
2979:
2976:
2975:
2974:
2971:
2951:Main article:
2948:
2945:
2931:
2928:
2925:
2922:
2916:
2913:
2910:
2905:
2902:
2899:
2893:
2887:
2884:
2881:
2878:
2875:
2870:
2867:
2864:
2861:
2858:
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2847:
2842:
2838:
2832:
2829:
2809:
2806:
2803:
2800:
2797:
2777:
2774:
2771:
2768:
2765:
2752:
2749:
2737:
2734:
2731:
2728:
2725:
2705:
2702:
2699:
2696:
2691:
2684:
2681:
2646:
2643:
2637:
2634:
2631:
2602:
2598:
2594:
2590:
2586:
2581:
2577:
2573:
2570:
2567:
2564:
2561:
2557:
2552:
2549:
2508:
2505:
2502:
2499:
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2448:
2412:
2405:
2402:
2378:
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2322:
2317:
2314:
2309:
2304:
2299:
2294:
2287:
2284:
2275:
2270:
2265:
2258:
2254:
2223:
2197:
2194:
2189:
2186:
2163:
2160:
2152:
2148:
2144:
2139:
2132:
2129:
2092:
2086:
2083:
2075:
2070:
2066:
2043:
2039:
2015:
2012:
1993:
1990:
1981:
1980:
1977:
1974:
1961:
1958:
1953:
1952:
1949:
1946:
1943:
1931:
1928:
1909:
1905:
1902:
1896:
1893:
1873:
1848:
1841:
1838:
1831:
1827:
1824:
1820:
1814:
1807:
1804:
1796:
1764:
1761:
1755:
1752:
1746:
1743:
1737:
1731:
1728:
1725:
1722:
1715:
1712:
1677:
1674:
1648:
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1639:
1618:
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1612:
1611:
1608:
1605:
1599:
1598:
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1592:
1588:
1587:
1584:
1581:
1577:
1576:
1573:
1570:
1566:
1565:
1562:
1559:
1555:
1554:
1551:
1548:
1547:TeflonâTeflon
1544:
1543:
1540:
1537:
1533:
1532:
1529:
1526:
1522:
1521:
1518:
1515:
1511:
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1507:
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1500:
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1471:
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1455:
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1427:
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1411:
1408:
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1400:
1397:
1394:
1362:
1359:
1356:
1333:
1330:
1305:
1298:
1295:
1268:
1248:
1228:
1225:
1211:
1205:
1202:
1196:
1191:
1188:
1184:
1179:
1176:
1173:
1170:
1163:
1160:
1153:
1122:
1119:
1116:
1113:
1106:
1103:
1077:
1074:
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1068:
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1023:
1016:
1013:
997:
994:
980:
974:
971:
965:
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957:
952:
947:
944:
941:
938:
931:
928:
921:
896:
893:
868:
865:
862:
859:
852:
849:
825:
799:
796:
793:
790:
783:
780:
754:
751:
748:
741:
738:
722:
719:
711:
710:
707:
701:
698:
695:
692:
681:
678:
673:
672:
669:
666:
663:
647:Main article:
644:
641:
638:
637:
562:. Please help
548:
546:
539:
533:
530:
518:Stribeck curve
512:Stribeck curve
510:Main article:
507:
506:Stribeck curve
504:
485:Main article:
482:
479:
466:Main article:
463:
460:
458:
455:
450:
449:
445:
437:
430:
411:
403:
359:
356:
330:
327:
295:, both of the
276:developed the
220:
219:
216:
185:
182:
172:
169:
106:
103:
84:tribocorrosion
15:
13:
10:
9:
6:
4:
3:
2:
6464:
6453:
6450:
6448:
6445:
6443:
6440:
6438:
6435:
6433:
6430:
6428:
6425:
6423:
6420:
6419:
6417:
6402:
6399:
6397:
6396:
6387:
6385:
6384:
6375:
6374:
6371:
6363:
6360:
6358:
6355:
6353:
6350:
6348:
6345:
6344:
6343:
6340:
6338:
6335:
6333:
6330:
6328:
6325:
6321:
6318:
6316:
6313:
6312:
6311:
6308:
6307:
6305:
6303:
6299:
6293:
6290:
6288:
6285:
6283:
6280:
6278:
6275:
6274:
6272:
6268:
6262:
6259:
6257:
6254:
6252:
6251:Computational
6249:
6247:
6244:
6243:
6241:
6237:
6231:
6227:
6224:
6222:
6219:
6217:
6214:
6213:
6211:
6207:
6203:
6195:
6190:
6188:
6183:
6181:
6176:
6175:
6172:
6164:
6158:
6157:cite magazine
6142:
6141:
6136:
6131:
6130:
6126:
6118:
6114:
6110:
6106:
6102:
6098:
6094:
6090:
6086:
6082:
6078:
6071:
6068:
6063:
6057:
6053:
6046:
6043:
6038:
6034:
6030:
6026:
6022:
6018:
6014:
6007:
6004:
5999:
5995:
5991:
5985:
5981:
5977:
5973:
5966:
5963:
5958:
5954:
5950:
5944:
5939:
5934:
5930:
5926:
5919:
5916:
5911:
5905:
5901:
5894:
5891:
5886:
5882:
5877:
5872:
5867:
5862:
5858:
5854:
5850:
5843:
5841:
5839:
5835:
5830:
5826:
5821:
5816:
5812:
5808:
5804:
5797:
5794:
5788:
5783:
5779:
5775:
5771:
5764:
5761:
5756:
5752:
5748:
5741:
5738:
5733:
5727:
5724:
5719:
5712:
5709:
5704:
5700:
5695:
5690:
5686:
5682:
5678:
5674:
5669:
5664:
5660:
5656:
5652:
5645:
5643:
5639:
5634:
5630:
5626:
5622:
5618:
5614:
5610:
5606:
5605:
5600:
5596:
5592:
5586:
5583:
5577:
5572:
5568:
5564:
5560:
5553:
5550:
5546:
5541:
5535:
5531:
5526:
5521:
5517:
5513:
5509:
5502:
5500:
5496:
5491:
5489:9780750611985
5485:
5481:
5474:
5471:
5466:
5464:9780198507772
5460:
5456:
5449:
5446:
5440:
5435:
5431:
5427:
5426:
5421:
5414:
5411:
5406:
5402:
5398:
5394:
5390:
5386:
5382:
5378:
5374:
5370:
5363:
5360:
5355:
5351:
5347:
5343:
5339:
5335:
5331:
5327:
5323:
5317:
5314:
5301:
5297:
5293:
5289:
5283:
5280:
5275:
5269:
5265:
5261:
5260:
5252:
5249:
5244:
5240:
5235:
5230:
5226:
5222:
5221:Gold Bulletin
5218:
5211:
5208:
5202:
5197:
5193:
5189:
5185:
5178:
5176:
5172:
5167:
5165:1-86058-070-X
5161:
5157:
5156:
5148:
5146:
5142:
5137:
5133:
5129:
5125:
5121:
5117:
5113:
5109:
5102:
5099:
5094:
5090:
5086:
5082:
5075:
5068:
5066:
5064:
5060:
5055:
5051:
5050:
5042:
5040:
5036:
5028:
5026:
5024:
5022:
5018:
5012:
5003:
5000:
4994:
4988:
4985:
4982:
4979:
4976:
4973:
4970:
4967:
4964:
4961:
4958:
4955:
4952:
4949:
4946:
4943:
4940:
4937:
4934:
4931:
4928:
4925:
4922:
4919:
4916:
4913:
4911:
4908:
4905:
4902:
4899:
4896:
4893:
4890:
4887:
4884:
4881:
4878:
4875:
4872:
4869:
4866:
4863:
4860:
4857:
4854:
4853:
4848:
4846:
4844:
4835:
4833:
4831:
4827:
4823:
4817:
4809:
4807:
4805:
4801:
4800:ionic liquids
4797:
4793:
4785:
4781:
4777:
4773:
4770:
4767:
4763:
4760:
4757:
4753:
4749:
4745:
4742:
4739:
4735:
4731:
4727:
4723:
4720:
4718:
4715:
4711:
4707:
4703:
4699:
4698:Nanotribology
4696:
4693:
4689:
4685:
4682:
4679:
4675:
4671:
4667:
4663:
4660:
4656:
4652:
4648:
4645:
4642:
4641:metal forming
4638:
4634:
4630:
4626:
4622:
4618:
4614:
4610:
4606:
4605:
4604:
4602:
4601:manufacturing
4598:
4594:
4590:
4581:
4574:
4569:
4567:
4565:
4561:
4556:
4554:
4553:manufacturing
4550:
4546:
4542:
4538:
4533:
4531:
4523:
4518:
4516:
4509:
4507:
4491:
4487:
4462:
4457:
4454:
4447:
4443:
4439:
4436:
4429:
4414:
4409:
4406:
4401:
4398:
4395:
4388:
4387:
4386:
4378:
4375:
4374:
4370:
4367:
4366:
4359:
4356:
4355:
4351:
4348:
4347:
4343:
4340:
4339:
4335:
4332:
4331:
4324:
4321:
4320:
4316:
4313:
4312:
4308:
4305:
4304:
4297:
4294:
4293:
4289:
4283:
4280:
4279:
4274:
4256:
4248:
4245:
4239:
4230:
4209:
4186:
4171:
4169:
4162:
4159:
4156:
4155:
4154:
4148:
4146:
4145:are made up.
4139:
4137:
4130:
4128:
4121:
4119:
4112:
4110:
4104:Abrasive wear
4103:
4101:
4099:
4091:
4087:
4084:
4081:
4078:
4075:
4072:
4071:
4070:
4064:Adhesive wear
4063:
4058:
4056:Erosion wear;
4055:
4052:
4049:
4047:Fatigue wear;
4046:
4043:
4040:
4039:
4038:
4035:
4029:
4021:
4019:
4013:
4010:
4007:
4006:
4005:
3999:
3997:
3983:
3961:
3957:
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3902:
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3886:
3883:
3873:
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3427:
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3419:
3418:
3414:
3411:
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3406:
3400:
3399:
3395:
3392:
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3385:
3371:
3349:
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3341:
3338:
3335:
3332:
3310:
3306:
3283:
3279:
3270:
3266:
3262:
3258:
3254:
3250:
3231:
3228:
3223:
3220:
3214:
3211:
3208:
3205:
3198:
3182:
3159:
3156:
3151:
3148:
3142:
3139:
3136:
3128:
3123:
3107:
3103:
3094:
3090:
3086:
3082:
3064:
3060:
3050:
3034:
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3007:
3003:
2994:
2989:
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2977:
2972:
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2963:
2960:
2954:
2946:
2944:
2929:
2926:
2923:
2920:
2914:
2911:
2908:
2903:
2900:
2897:
2891:
2885:
2882:
2879:
2876:
2873:
2868:
2865:
2862:
2859:
2856:
2850:
2845:
2840:
2836:
2830:
2827:
2807:
2804:
2801:
2798:
2795:
2775:
2772:
2769:
2766:
2763:
2750:
2748:
2735:
2732:
2729:
2726:
2723:
2703:
2700:
2697:
2694:
2689:
2679:
2667:
2663:
2641:
2635:
2632:
2629:
2619:
2600:
2596:
2592:
2579:
2575:
2571:
2568:
2562:
2555:
2550:
2547:
2539:
2535:
2531:
2526:
2524:
2506:
2503:
2500:
2497:
2493:
2489:
2486:
2483:
2480:
2459:
2456:
2453:
2450:
2446:
2437:
2432:
2426:
2410:
2400:
2376:
2354:
2349:
2344:
2339:
2329:
2320:
2315:
2312:
2307:
2302:
2297:
2292:
2282:
2273:
2268:
2263:
2256:
2252:
2239:
2237:
2221:
2213:
2195:
2192:
2187:
2184:
2158:
2150:
2146:
2142:
2137:
2127:
2115:
2112:
2106:
2090:
2081:
2073:
2068:
2064:
2041:
2037:
2010:
1999:
1991:
1989:
1985:
1978:
1975:
1972:
1971:
1970:
1967:
1959:
1957:
1950:
1947:
1944:
1941:
1940:
1939:
1936:
1929:
1927:
1925:
1907:
1903:
1900:
1894:
1891:
1871:
1863:
1836:
1825:
1822:
1812:
1802:
1784:
1780:
1759:
1753:
1750:
1741:
1735:
1729:
1726:
1723:
1720:
1710:
1697:
1692:
1672:
1643:
1637:
1623:
1616:
1609:
1606:
1604:
1601:
1600:
1596:
1593:
1591:Copperâglass
1590:
1589:
1585:
1582:
1580:Copperâsteel
1579:
1578:
1574:
1571:
1568:
1567:
1563:
1560:
1557:
1556:
1552:
1549:
1546:
1545:
1541:
1538:
1536:SteelâTeflon
1535:
1534:
1530:
1527:
1524:
1523:
1519:
1516:
1513:
1512:
1508:
1505:
1502:
1501:
1497:
1494:
1491:
1490:
1486:
1483:
1480:
1479:
1475:
1472:
1469:
1468:
1464:
1461:
1458:
1457:
1453:
1450:
1447:
1446:
1442:
1439:
1436:
1435:
1431:
1428:
1425:
1424:
1420:
1417:
1414:
1413:
1409:
1406:
1403:
1402:
1398:
1395:
1392:
1391:
1385:
1382:
1378:
1374:
1360:
1357:
1354:
1328:
1303:
1293:
1280:
1266:
1246:
1233:
1226:
1224:
1209:
1200:
1194:
1189:
1186:
1182:
1177:
1174:
1171:
1168:
1158:
1151:
1142:
1138:
1120:
1117:
1114:
1111:
1101:
1075:
1072:
1069:
1066:
1056:
1030:
1027:
1024:
1021:
1011:
995:
993:
978:
969:
963:
958:
955:
950:
945:
942:
939:
936:
926:
919:
891:
866:
863:
860:
857:
847:
823:
813:
797:
794:
791:
788:
778:
752:
749:
746:
736:
720:
718:
715:
708:
706:
703:Third Law of
702:
699:
696:
693:
691:
688:First Law of
687:
686:
685:
679:
677:
670:
667:
664:
661:
660:
659:
656:
650:
642:
634:
631:
623:
612:
609:
605:
602:
598:
595:
591:
588:
584:
581: â
580:
576:
575:Find sources:
569:
565:
561:
555:
554:
549:This section
547:
543:
538:
537:
531:
529:
527:
523:
519:
513:
505:
503:
501:
497:
493:
488:
480:
478:
475:
469:
461:
456:
454:
443:
435:
431:
428:
424:
423:manufacturing
420:
417:(25%) and in
416:
412:
409:
404:
401:
400:
399:
397:
393:
389:
388:manufacturing
385:
381:
377:
373:
369:
365:
357:
355:
352:
348:
344:
342:
336:
328:
326:
324:
323:ancient Egypt
320:
316:
312:
311:Duncan Dowson
308:
306:
302:
298:
294:
290:
285:
283:
279:
275:
269:
264:
260:
256:
252:
248:
244:
240:
236:
231:
229:
225:
217:
214:
213:
212:
210:
206:
201:
199:
195:
191:
184:Early history
183:
177:
170:
168:
166:
162:
158:
154:
150:
149:
142:
136:
135:
130:
129:
122:
116:
112:
104:
102:
99:
97:
93:
89:
85:
81:
77:
73:
72:nanotribology
69:
65:
61:
57:
53:
49:
45:
41:
37:
33:
29:
25:
21:
6393:
6381:
6286:
6209:Main classes
6200:Branches of
6145:. Retrieved
6138:
6084:
6080:
6070:
6054:. Elsevier.
6051:
6045:
6020:
6016:
6006:
5971:
5965:
5928:
5918:
5902:. Springer.
5899:
5893:
5856:
5852:
5810:
5806:
5796:
5777:
5773:
5763:
5746:
5740:
5731:
5726:
5717:
5711:
5658:
5654:
5608:
5602:
5585:
5566:
5562:
5552:
5515:
5511:
5479:
5473:
5454:
5448:
5429:
5423:
5413:
5372:
5368:
5362:
5329:
5325:
5316:
5304:. Retrieved
5299:
5295:
5282:
5263:
5258:
5251:
5224:
5220:
5210:
5191:
5187:
5154:
5111:
5107:
5101:
5084:
5080:
5053:
5047:
5002:
4933:Oil analysis
4927:Oil additive
4868:Cold welding
4839:
4819:
4789:
4726:multiphysics
4684:Geotribology
4647:Biotribology
4586:
4557:
4534:
4527:
4519:Applications
4513:
4478:
4384:
4290:Usage level
4175:
4166:
4152:
4143:
4140:Erosion wear
4134:
4125:
4116:
4113:Fatigue wear
4107:
4095:
4089:
4079:Law 2 â Load
4067:
4031:
4017:
4003:
3874:
3721:
3635:
3621:
3618:
3596:
3562:
3476:
3268:
3264:
3260:
3256:
3252:
3248:
3197:Newton's law
3126:
3124:
3092:
3088:
3084:
3080:
3051:
2993:laminar flow
2990:
2987:
2964:
2956:
2754:
2665:
2661:
2620:
2537:
2536:= 0 and for
2533:
2529:
2527:
2522:
2521:with 0 <
2435:
2427:
2240:
2235:
2211:
2113:
2111:shear stress
2107:
1995:
1986:
1982:
1963:
1954:
1937:
1933:
1930:The surfaces
1923:
1861:
1785:
1781:
1695:
1693:
1628:
1514:Steelâbrass
1448:Glassâglass
1383:
1379:
1375:
1281:
1238:
1140:
1136:
999:
814:
724:
712:
683:
674:
652:
626:
617:
607:
600:
593:
586:
574:
553:verification
550:
515:
490:
474:tribosystems
471:
451:
361:
358:Significance
338:
334:
332:
314:
309:
304:
300:
286:
259:Theodor Reye
232:
221:
202:
187:
146:
132:
126:
110:
108:
100:
68:biotribology
64:tribosystems
19:
18:
6261:Informatics
5432:: 425â459.
5375:(53): 317.
4951:Sclerometer
4921:Lubrication
4843:tribometers
4752:outer space
4659:lubrication
2953:Lubrication
2947:Lubrication
910:, obtaining
620:August 2019
579:"Tribology"
468:Tribosystem
462:Tribosystem
427:residential
396:residential
380:Ali Erdemir
319:Mesopotamia
293:David Tabor
272:. In 1953,
266: [
60:engineering
52:mathematics
28:lubrication
6447:Metallurgy
6416:Categories
6327:Mineralogy
6216:Metallurgy
5013:References
4975:Tribometer
4939:Peter Jost
4549:lubricants
4545:efficiency
3431:0.32 â
10
3396:ÎŒ(Pa â
s)
2959:lubricants
2431:third body
1998:asperities
1984:involved.
1966:asperities
1525:Steelâair
1481:Steelâice
1404:Woodâwood
590:newspapers
492:Tribofilms
255:gold coins
153:Peter Jost
6422:Tribology
6310:Chemistry
6287:Tribology
6037:247398788
5998:238793302
5957:2195-9862
5885:2223-7690
5668:1202.1716
5633:0002-9505
5534:2223-7690
5397:0080-4606
5354:0021-8979
5302:: 235â255
5243:0017-1557
5128:1520-6106
5052:. No. 5.
4995:Footnotes
4915:Lubricant
4810:Societies
4670:lifecycle
4611:(such as
4597:transport
4537:transport
4301:Moderate
4254:Δ
4246:δ
4207:Δ
4184:Δ
4172:Wear rate
3984:α
3958:μ
3937:μ
3910:α
3903:
3891:μ
3884:μ
3848:
3824:
3818:−
3806:
3756:−
3693:×
3684:−
3666:−
3579:≃
3549:μ
3529:ρ
3507:μ
3497:ρ
3468:Glycerin
3447:4.0 â
10
3439:1.0 â
10
3423:2.9 â
10
3420:Gasoline
3415:1.8 â
10
3407:1.5 â
10
3372:μ
3339:μ
3212:μ
3183:μ
3140:∝
2984:Viscosity
2978:Viscosity
2930:θ
2927:
2915:θ
2912:
2904:θ
2901:
2886:θ
2883:
2869:θ
2866:
2828:μ
2808:θ
2805:
2776:θ
2773:
2724:μ
2683:→
2645:→
2572:−
2563:α
2548:μ
2490:⋅
2404:→
2377:α
2333:→
2316:α
2286:→
2222:μ
2185:μ
2162:→
2131:→
2085:→
2014:→
1901:μ
1872:μ
1840:→
1806:→
1763:→
1751:×
1745:→
1714:→
1676:→
1647:→
1407:0.25â0.5
1355:μ
1332:→
1297:→
1247:μ
1204:→
1162:→
1105:→
1060:→
1015:→
973:→
959:μ
956:≤
930:→
895:→
851:→
824:μ
782:→
740:→
653:The word
560:talk page
526:viscosity
487:Tribofilm
481:Tribofilm
415:transport
384:transport
335:tribology
333:The term
284:contact.
261:proposed
233:In 1798,
165:corrosion
111:tribology
109:The word
105:Etymology
80:corrosion
44:chemistry
20:Tribology
6427:Friction
6401:Material
6383:Category
6117:26811802
6109:15089689
5853:Friction
5829:44071702
5774:Friction
5703:23545778
5661:: 1586.
5512:Friction
5405:71069997
5188:Friction
5136:16643851
4886:Friction
4880:Fretting
4849:See also
4796:graphene
4784:Big Data
4688:glaciers
4674:friction
4651:friction
4649:studies
4629:clutches
4570:Research
4530:bearings
4379:10 â 10
4371:10 â 10
4360:10 â 10
4352:10 â 10
4344:10 â 10
4336:10 â 10
4325:10 â 10
4317:10 â 10
4309:10 â 10
4298:10 â 10
4157:Hardness
3267:, where
2525:< 1.
1783:motion.
1451:0.9â1.0
1426:Iceâice
690:Amontons
655:friction
649:Friction
643:Friction
496:friction
364:friction
282:asperity
253:rate of
228:friction
205:friction
198:friction
190:friction
157:friction
92:friction
86:and the
24:friction
6342:Physics
6270:Domains
6089:Bibcode
5751:Bibcode
5718:Physics
5694:3613807
5673:Bibcode
5613:Bibcode
5377:Bibcode
5334:Bibcode
4898:Galling
4862:Bearing
4363:Severe
4328:Medium
3766:0.00715
1922:, with
714:Coulomb
705:Coulomb
604:scholar
532:Physics
171:History
56:biology
40:physics
6395:Common
6147:6 June
6115:
6107:
6058:
6035:
5996:
5986:
5955:
5945:
5906:
5883:
5827:
5701:
5691:
5631:
5532:
5486:
5461:
5403:
5395:
5352:
5306:25 May
5270:
5241:
5162:
5134:
5126:
4692:faults
4633:wheels
4625:brakes
4575:Fields
4281:Class
3929:where
3393:Fluid
1610:0.003
1531:0.001
1528:0.001
606:
599:
592:
585:
577:
394:, and
343:Report
148:-logia
141:-λογία
36:motion
6113:S2CID
6033:S2CID
5994:S2CID
5825:S2CID
5663:arXiv
5401:S2CID
5262:[
5132:S2CID
5077:(PDF)
4617:gears
4589:macro
4286:usury
3463:0.11
3455:0.03
2532:= 0,
2369:with
1607:0.01
1597:0.53
1594:0.68
1586:0.36
1583:0.53
1553:0.04
1550:0.04
1542:0.04
1539:0.04
1520:0.44
1517:0.51
1509:0.47
1506:0.61
1498:0.42
1495:0.78
1487:0.05
1476:0.05
1473:0.09
1443:0.04
1440:0.04
1432:0.02
1421:0.23
1418:0.32
611:JSTOR
597:books
442:Euros
270:]
137:from
134:-logy
128:tribo
121:ÏÏÎŻÎČÏ
115:Greek
6228:and
6163:link
6149:2022
6105:PMID
6056:ISBN
5984:ISBN
5953:ISSN
5943:ISBN
5904:ISBN
5881:ISSN
5699:PMID
5629:ISSN
5530:ISSN
5484:ISBN
5459:ISBN
5393:ISSN
5350:ISSN
5308:2018
5268:ISBN
5239:ISSN
5160:ISBN
5124:ISSN
5081:Wear
4981:Wear
4828:and
4798:and
4782:and
4736:and
4710:NEMS
4706:MEMS
4690:and
4678:wear
4676:and
4657:and
4655:wear
4635:and
4599:and
4593:nano
4560:wear
4235:wear
4090:less
4034:wear
4032:The
4028:Wear
4022:Wear
3835:Test
3674:Test
3582:2000
3471:1.5
3412:Air
3298:and
1575:0.5
1572:0.7
1564:0.8
1561:1.0
1484:0.1
1465:0.6
1462:0.6
1454:0.4
1429:0.1
1410:0.2
1358:>
583:news
516:The
500:wear
498:and
425:and
368:wear
366:and
341:Jost
339:The
251:wear
243:wear
237:and
163:and
161:wear
96:wear
94:and
74:and
58:and
32:wear
30:and
6097:doi
6025:doi
5976:doi
5933:doi
5871:hdl
5861:doi
5815:doi
5782:doi
5689:PMC
5681:doi
5621:doi
5571:doi
5520:doi
5434:doi
5385:doi
5342:doi
5229:doi
5196:doi
5116:doi
5112:108
5089:doi
5085:360
5054:281
4750:of
4591:to
3900:exp
3845:Log
3821:Log
3803:Log
3775:100
3696:100
2924:tan
2909:cos
2898:sin
2880:cos
2863:sin
2802:sin
2770:cos
1884:as
566:by
408:GDP
370:on
347:GDP
6418::
6159:}}
6155:{{
6137:.
6111:.
6103:.
6095:.
6085:92
6083:.
6079:.
6031:.
6021:40
6019:.
6015:.
5992:.
5982:.
5951:.
5941:.
5931:.
5927:.
5879:.
5869:.
5855:.
5851:.
5837:^
5823:.
5811:31
5809:.
5805:.
5776:.
5772:.
5697:.
5687:.
5679:.
5671:.
5657:.
5653:.
5641:^
5627:.
5619:.
5609:33
5607:.
5597:;
5593:;
5569:.
5565:.
5561:.
5528:.
5514:.
5510:.
5498:^
5430:54
5428:.
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