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The purpose of this paper is to describe the construction of a custom‐built pin‐on‐disk (POD) apparatus based on a simple design and on important guidelines.

The POD apparatus is built as a part of the main author's PhD project. The apparatus is built at a low cost and is suited for testing polymeric materials under dry‐sliding conditions. The different main parts of the apparatus are described in a way which partly explains the choice of construction and partly makes it possible to produce a similar apparatus. Furthermore, a limited amount of tribological data is presented mainly to exemplify the usefulness of the machine.

The POD apparatus is successfully applied to measure coefficients of friction, wear rates and disk temperatures at an acceptable level of precision and accuracy. Tribological data obtained with this equipment show the effect of reinforcing an epoxy resin with a plain glass fiber weave.

The data presented in this paper are limited since the main objective is to describe the construction of a POD apparatus.

The paper is intended to be a source of inspiration for industrial or academic laboratories who want to establish their own tailor‐suited tribological test‐equipment, instead of investing in a probably more expensive commercial machine.

The POD apparatus is custom‐built and described in an easily understandable way, which makes this a helpful paper for those who wish to produce a similar apparatus.

The purpose of the present paper aims to, study the coefficient of friction and wear behavior of nickel based super alloys used in manufacturing of gas and steam turbine blades. In present paper, parametric study focuses on normal load, dry sliding velocity and contact temperature influence on coefficient of friction and wear of a nickel based super alloy material.

Experimental investigation is carried out to know the effect of varying load at constant sliding velocity and varying sliding velocity at constant load on coefficient of friction and wear behavior of nickel based super alloy material. The experiments are carried out on a nickel based super alloy material using pin on disk apparatus by load ranging from 30 N to 90 N and sliding velocity from 1.34 m/s to 2.67 m/s. The contact temperature between pin and disk is measured using K-type thermocouple for all test conditions to know effect of contact temperature on coefficient of friction and wear behavior of nickel based super alloy material. Analytical calculations are carried out to find wear rate and wear coefficient of the test specimen and are compared with experimental results for validation of experimental setup. Regression equations are generated from experimental results to estimate coefficient of friction and wear in the range of test conditions.

From the experimental results, it is observed that by increasing the normal load or sliding velocity, the contact temperature between the pin and disk increases, the coefficient of friction decreases and wear increases. Analysis of variance (ANOVA) is used to study the influence of individual parameters like normal load, dry sliding speed and sliding distance on the coefficient of friction and wear of nickel based super alloy material.

This is the first time to study effect of contact temperature on the coefficient of friction and wear behavior of nickel-based super alloy used for gas and steam turbine blades. Separate regression equations have been developed to determine the coefficient of friction and wear for the entire range of speed of gas turbine blades made of nickel based super alloy. The regression equations are also validated against experimental results.

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.

Recent trends in material science show a considerable interest in the manufacturing of metal matrix composites to meet the stringent demands of lightweight, high strength and corrosion resistance. Aluminium is the popular matrix metal currently in vogue that can be reinforced with ceramic materials such as particulates to meet the desired property. The purpose of this paper is to fabricate hybrid metal matrix composites to improve the dry sliding wear resistance and to study of the effect of sliding speed, load and reinforcement (alumina and graphite) on wear properties, as well as its contact friction.

The present study addresses the dry sliding wear behaviour of Al‐Si10Mg alloy reinforced with 3, 6 and 9 wt% of alumina along with 3 wt% of graphite. Stir casting method was used to fabricate the composites. Mechanical properties such as hardness and tensile strength have been evaluated. A pin‐on‐disc wear test apparatus was used to evaluate the wear rate and coefficient of friction by varying the loads of 20, 30 and 40 N, sliding speeds of 1.5 m/s, 2.5 m/s and 3.5 m/s at a constant sliding distance of 2100 m.

Mechanical properties of hybrid metal matrix composites (HMMCs) have shown significant improvement. The wear rate and coefficient of friction for alloy and composites decreased with increase in sliding speed and increased with increase in applied load. Temperature rise during wearing process for monolithic alloy was larger than that of HMMCs and Al/9% Al₂O₃/3% Gr composite showing the minimum temperature rise.The worn surfaces of the composites were investigated using scanning electron microscope.

The paper shows that aluminium composites can improve strength and wear resistance.

HMMCs has proven to be useful in improving the dry sliding wear resistance.

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 purpose of this technical paper is to investigate the friction and wear behaviour of heat treated Al 6061 alloy and Al 6061 SiC‐graphite particulate reinforced hybrid composites subjected to different ageing durations.

The composites have been prepared by stir casting process with varying percentages of SiC and graphite particles. The cast 6061 alloy and its composites were subjected to solutionising treatment at a temperature of 803 K for 1 hr followed by quenching in water. The quenched samples were then subjected to artificial ageing for different durations of 4, 6, 8 hr at a temperature of 448 K. Tests were performed on heat treated Al 6061 alloy and its composites using pin‐on‐disc apparatus. Hardness measurements were also made on the specimens. The wear surfaces of the composites were analyzed using scanning electron microscopy.

During wear test of specimens the wear resistance of the hybrid composites was found to increase with increase in ageing durations. The microscopic examination of the wear surfaces shows that the base alloy and composites wear primarily because of abrasion and delamination. The hardness result shows that the hardness of the composites increased with decreasing weight percentage of graphite particles.

The content of this paper is fully research oriented and the finding from this investigation will be useful for society and also the automobile industries, especially in the making of brake drums.

The purpose of this paper is to investigate the influence of most predominant heat-treatment parameters on the wear behavior of Al6061 hybrid composite reinforced with 10 weight per cent SiC and 2 weight per cent graphite particles.

The aluminum hybrid composite was produced using stir casting process. Wear testing of heat-treated samples was carried out using a pin-on-disc apparatus. Experiments were conducted by applying design of experiments (DOE) technique. The experimental values were used for formulation of a mathematical model. The wear surfaces of composite specimens were analyzed using scanning electron microscope (SEM).

The volume loss of heat-treated composite initially decreased with increasing aging duration. This was followed by the attainment of a minimum and then a reversal in the trend at longer aging times. SEM micrographs of the wear surfaces of the composite show that the wear mechanisms were abrasion, delamination and adhesion.

In this paper, the hybrid composite was produced using stir casting route, and its wear properties after heat treatment were tested using pin-on-disc apparatus. It was found that heat treatment had a profound effect on the wear behaviour of the developed composite.

In an internal combustion engine, piston ring-cylinder liner tribo pair is one among the most critical rubbing pairs. Most of the energy produced by an internal combustion engine is dissipated as frictional losses of which major portion is contributed by the piston ring-cylinder liner tribo pair. Hence, proper design of tribological parameters of piston ring-cylinder liner pair is essential and can effectively reduce the friction and wear, thereby improving the tribological performance of the engine. This paper aims to use surface texturing, an effective and feasible method, to improve the tribological performance of piston ring-cylinder liner tribo pair.

In this paper, influence of positive texturing (protruding) on friction reduction and wear resistance of piston ring surfaces was studied. The square-shaped positive textures were fabricated on piston ring surface by chemical etching method, and the experiments were conducted with textured piston ring surfaces against un-textured cylinder liner surface on pin-on-disc apparatus by continuous supply of lubricant at the inlet of contact zone. The parameters varied in this study are area density and normal load at a constant sliding speed. A comparison was made between the tribological properties of textured and un-textured piston ring surfaces.

From the experimental results, the tribological performance of the textured piston ring-cylinder liner tribo pair was significantly improved over a un-textured tribo pair. A maximum friction reduction of 67.6 per cent and wear resistance of 81.6 per cent were observed with textured ring surfaces as compared to un-textured ring surfaces.

This experimental study is helpful for better understanding of the potency of positive texturing on friction reduction and wear resistance of piston ring-cylinder liner tribo pair under lubricated sliding conditions.

The purpose of this paper is to evaluate experimentally the influence of different surface roughness of the contacting disc on tribological performance of the non-asbestos brake friction material (BFM).

Taguchi method was applied to design an experiment using three different discs of gray cast iron with different surface roughness, which is measured using optical profilometer. These discs were subjected to sliding against pins prepared with the developed non-asbestos BFM, using pin on disc friction and wear monitor.

The experimental results shows that the disc 2 (Ra = 3.77 µm) gives wear of 22.78 µm and coefficient of friction of 0.462, which is recommended for extreme brake performance. Analysis of Taguchi design revealed that the disc surface was most significant parameter among the parameters under study.

During braking, continuous sliding between the BFM and brake disc or drum not only results into wear of BFM but also changes the surface finish of the brake drum or disc. This leads to variation in surface topography of the drum or disc surface with application of brakes, which further affects the characteristics of the BFM.

The tribological performance of BFM depends upon the topography of the surface on which it was sliding. To get best performance of the non-asbestos friction materials, disc having moderate surface finish is recommended. Scanning electron microscope micrographs had shown the different plateaus formed and energy-dispersive X-ray spectroscopy spectra identified presence of different chemical elements prior to sliding of the pins surface over different discs surface topography.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2020-0120/

The present paper seeks to report the effect of duration of rubbing on friction coefficient for different polymer and composite materials. Variations of friction coefficient and wear rate with the normal load are also investigated experimentally when stainless steel (SS 304) pin slides on different types of materials such as cloth‐reinforced ebonite (commercially known as gear fiber), glass fiber‐reinforced plastic (glass fiber), nylon and polytetrafluoroethylene (PTFE).

A pin on disc apparatus is designed and fabricated. During experiment, the rpm of test samples was kept constant and relative humidity was 70 percent.

Studies have shown that the values of friction coefficient depend on applied load and duration of rubbing. It is observed that the values of friction coefficient decrease with the increase of normal load for glass fiber, nylon and PTFE. Different trend is observed for gear fiber, i.e. coefficient of friction increases with the increase of normal load. It is also found that wear rate increases with the increase of normal load for all the materials. The magnitudes of friction coefficient and wear rate are different for different materials.

It is expected that the applications of these results will contribute to the design of different mechanical components of these materials.

Within the observed range of applied normal load, the relative friction coefficient and wear rate of gear fiber, glass fiber, nylon and PTFE are experimentally investigated.