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The role that lubricating oils play is, first of all, to reduce energy loss and keep the wear and seizure to a minimum, or, in a broader sense, to improve the friction characteristics. Resistance to deterioration and prevention of rust development on metals are demanded as secondary functions. The time during which lubricating oil retains its ability to prevent any possible damage to a body in motion should be considered as its lifetime. Many functions that are provided by base oil alone are insufficient; therefore, special additives are dissolved in them. The additives for lubricating oils are of many types, and their functions are diverse and many. Those additives that are used with the purpose of improving friction characteristics are generally called oiliness improvers or friction modifiers. In this study, the protective additive's layers formed on rubbed surfaces of pins, plates and discs were investigated using pin‐on‐disc and reciprocating pin‐on‐plate test rigs. Wear tracks were examined using optical and electron microscopy with X‐ray diffraction analysis.

The aim of this study is to calculate the coefficient of friction of wheel/rail interface in both water lubrication and dry friction conditions.

Specimens taken from wheel and rail used in railway transport were exposed to pin‐on‐disc wear testing with 10, 20, 30 and 40 N loads. The disc took the place of the rail and the pin that of the wheel in wear tests, and rain water was fed to the disc/pin interface with a three drops/min speed in wet friction conditions. The coefficient of friction and weight loss values of specimens were determined and types of wear mechanism were characterized.

It was observed that the friction coefficient decreased in wet sliding experiments, so smaller values were calculated in wet friction conditions than those of dry friction conditions for wheel specimens. However, this decrease was more drastic for rail specimens. Weight and volumetric loss values of rail materials were lower than those of wheel samples.

This study investigates the wet and dry sliding wear characteristics of train wheel‐rail materials.

In this study, the tri-bological behaviour of the un-coated and diamond coated tungsten carbide was evaluated using the pin-on-disc test rig. The same was also tested on a lathe machine tool. This paper aims to compare the tri-bological behaviour of coated tungsten carbide pin with un-coated tungsten carbide pin it also correlates the wear obtained from the two machines used.

Experiments were performed using L8 orthogonal array and results obtained on a pin-on-disc test rig under dry sliding process were optimized through a modern optimization technique i.e. genetic algorithm (GA). The response surface methodology model (L8 orthogonal array) formed the basis for the development of the GA model, which defines the conditions of minimum wear, minimum coefficient of friction and minimum surface roughness for the sliding process of the pin-on-disc test rig.

Implementation of the heuristic approach for optimization of input parameters for the combination of tool material used for the turning process. The initial approach involves tri-bological testing considering the same combination. The set of experiments further performed, inferred that the results were similar and that the diamond coating enhances the life of the tool.

Successfully synthesized the diamond coating on tungsten carbide tool material. Implantation of the heuristic approach, i.e. GA to tri-bological tests to identify the optimized level of input variables. Experimentation involves the tri-bological testing whose results were confirmed through performing experiments on the lathe machine tool.

Sliding wear is a common phenomenon in the iron ore handling industry. Large-scale handling of iron ore bulk-solids causes a high amount of volume loss from the surfaces of bulk-solids-handling equipment. Predicting the sliding wear volume from equipment surfaces is beneficial for efficient maintenance of worn equipment. Recently, the discrete element method (DEM) simulations have been utilised to predict the wear by bulk-solids. However, the sensitivity of wear prediction subjected to DEM parameters has not been systemically investigated at single particle level. To ensure the wear predictions by DEM are accurate and stable, this study aims to conduct the sensitivity analysis at the single particle level.

In this research, pin-on-disc wear tests are modelled to predict the sliding wear by individual iron ore particles. The Hertz–Mindlin (no slip) contact model is implemented to simulate interactions between particle (pin) and geometry (disc). To quantify the wear from geometry surface, a sliding wear equation derived from Archard’s wear model is adopted in the DEM simulations. The accuracy of the pin-on-disc wear test simulation is assessed by comparing the predicted wear volume with that of the theoretical calculation. The stability is evaluated by repetitive tests of a reference case. At the steady-state wear, the sensitivity analysis is done by predicting sliding wear volumes using the parameter values determined by iron ore-handling conditions. This research is carried out using the software EDEM^® 2.7.1.

Numerical errors occur when a particle passes a joint side of geometry meshes. However, this influence is negligible compared to total wear volume of a wear revolution. A reference case study demonstrates that accurate and stable results of sliding wear volume can be achieved. For the sliding wear at steady state, increasing particle density or radius causes more wear, whereas, by contrast, particle Poisson’s ratio, particle shear modulus, geometry mesh size, rotating speed, coefficient of restitution and time step have no impact on wear volume. As expected, increasing indentation force results in a proportional increase. For maintaining wear characteristic and reducing simulation time, the geometry mesh size is recommended. To further reduce simulation time, it is inappropriate using lower particle shear modulus. However, the maximum time step can be increased to 187% T_R without compromising simulation accuracy.

The applied coefficient of sliding wear is determined based on theoretical and experimental studies of a spherical head of iron ore particle. To predict realistic volume loss in the iron ore-handling industry, this coefficient should be experimentally determined by taking into account the non-spherical shapes of iron ore particles.

The effects of DEM parameters on sliding wear are revealed, enabling the selections of adequate values to predict sliding wear in the iron ore-handling industry.

The accuracy and stability to predict sliding wear by using EDEM^® 2.7.1 are verified. Besides, this research accelerates the calibration of sliding wear prediction by DEM.

Outlines the various testing procedures carried out by BICERI, including engine fuel and lubricant testing. Describes the universal wear machine, and explains the three test modes: pin‐on disc, block‐on‐ring and pin‐on‐reciprocating plate.

The purpose of this study was to investigate wear behaviours of brake pads produced from carbon–carbon (C/C) composites in both wet and dry friction sliding conditions. Carbon is probably the most remarkable element in science and also C/C composites are a family of advanced composite materials. They are the most advanced form of carbon and consist of fibre based on carbon precursors embedded in a carbon matrix. In the present work, wear test specimens were prepared according to the related standards and they were exposed to pin-on-disc wear testing in wet and dry sliding conditions with different loads as 10, 20, 30 and 40 N with 1 m/s constant sliding speed. Wet friction process was conducted on all specimens by means of rain water collected from the nature.

Pin-on-disc wear test tribology lubrication was used.

Mechanical and physical property measurements of C/C composite brake pad materials: hardness, modulus of elasticity, density and water absorption capacity. Wear performance of materials were measured as coefficient of friction, volumetric loss and specific wear rate.

C/C composite brake pads are used in railway vehicles. Wear performances of them are very important for safety. In this study, wear behaviours of these materials were investigated not only in dry sliding friction condition but also in wet sliding one. Because safety braking is important in all weather conditions for trains, and we used natural rain water to observe the wet sliding friction behaviour of brake pads. “Water lubrication” is an important aspect mentioned in tribology handbooks.

The purpose of this paper is to understand the influence of reinforced fiber length over material‐plastic energy of deformation, clogging, crystallinity, and correlates with the friction and wear behavior of polypropylene (PP) composites under multi‐pass abrasive condition. Also to identify wear mechanisms of glass fiber reinforced PP materials under various abrasive grit sizes and normal loads.

Multi‐pass abrasive wear tests were performed for unreinforced, short, and long glass fiber reinforced PP (LFPP) on a pin on disc machine under three different normal loads and two different abrasive grit sizes for a constant sliding velocity. Measured wear volume was correlated with the plastic energy of deformation by carrying out a constant load indentation test using servo hydraulic fatigue test system. Clogging behavior of test materials was examined with the aid of online wear measurement and wear morphology. Test materials crystallinity was estimated with the aid of X‐ray diffraction investigation and correlated with abrasive wear performance.

Fiber reinforcement in a PP material is found to improve the plastic deformation energy and crystallinity which results in improved abrasive resistance of the material. Increase in reinforced fiber length is found to improve the material cohesive energy and hence the wear resistance. Reinforcement is found to alter the material clogging behavior under multi‐pass condition. Fiber reinforcement is found to reduce the material coefficient of friction, and increase in reinforced fiber length further reduces the frictional coefficient.

Friction wear tests using pin on disc equipment is carried out in the present investigation. However, in practice, part geometry may not be always equivalent to simple pin on disc configuration.

The paper's investigation results could help to improve the utilization of LFPP material in many structural applications.

Influence of reinforced fiber length over multi‐pass abrasive wear performance of thermoplastic material, and online wear measurement to substantiate clogging behavior is unique in the present multi‐pass abrasive investigation.

Commercial oil fortifier was added to fully‐formulated crankcase oils, and their performance, in terms of friction, wear and, most importantly, the role of the additive protective layer on the sliding surfaces, was investigated. Tests were performed on a pin‐on‐disc machine using steel and steel sliding partners under boundary lubrication conditions. Tests were carried out at a constant load and velocity at different temperatures with different lubricants and the results were achieved using analytical methods such as light microscopy, electron microscopy and X‐ray diffraction. Related to the experimental work, lubricants and the lubricants containing oil fortifier presented satisfactory protective additive layers which were identified on the wear track at high and low temperatures.

The purpose of this study is to develop new Al‐based bearing alloys which have better properties than classic commercial bearing materials and to analyze tribologic properties of these alloys under dry sliding conditions experimentally.

Four different aluminium alloys were produced with casting method and tested on pin‐on‐disc wear testing machine. Friction coefficients and weight losses of the samples were determined under various working conditions in consequence of the experiments. Hardness, surface roughness, and surface temperatures of the samples were measured.

The results of the experiment show that friction coefficients vary by surface pressure and sliding speed. Al15Pb3.7Cu1.5Si1.1Fe and Al15Sn5Cu3Si alloys have lower friction coefficient values than other alloys. Al8.5Si3.5Cu alloy has the biggest wear resistance. Al15Pb3.7Cu1.5Si1.1Fe and Al15Sn5Cu3Si alloys are the most worn materials. Al8.5Si3.5Cu alloy has the lowest wear rate.

When the comparison was done between commercial Al alloys and developed Al alloys in this study, it was seen that Al15Sn5Cu3Si and Al15Pb3.7Cu1.5Si1.1Fe alloys have lower friction coefficient values than other commercial alloys.

The effects of the elements except aluminium composing alloys upon tribologic properties were analyzed. Some of the alloy elements were seen to improve tribologic properties whereas some downgrade. When the results are evaluated, Al15Sn5Cu3Si and Al8.5Si3.5Cu alloys containing Si and Sn can be preferred among the aluminium alloys that will work under dry sliding.

This paper reveals new bearing materials. These alloys can be used in journal bearings.

Artificial biomaterials are implanted to the human body to support the structure depending upon the extent of deformity or damage. This paper aims to formulate an experimental approach to assess the suitability of materials that can be used in the manufacture of human implants.

Five different pin materials such as SS304, Alumina, HDPE, UHMWPE and Brass have been chosen to be suitable for implants. The tribological properties of the aforementioned materials have been tested on a simple pin-on-disc apparatus. EN31 was chosen as the disc material because its hardness value is much higher than that of the pin materials used. The test materials were constructed in the form of spherical end pins to have point contacts and to reduce the depth of wear.

It has been observed that the polymeric (HDPE and UHMWPE) and ceramic materials (Alumina) are much better than the traditional metallic materials. The wear rate is very low for these materials owing to their self-lubricating properties.

The experimental studies will help predict the performance and life of implant materials in the human body.

In most cases, SS316L that possesses nickel compositions is used as the disc material; SS316L is toxic to the human body. In the present study, a high carbon alloy steel with high degrees of hardness EN31 is used as a disc counter-face material.