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This paper aims to present the methodology to determine Archard’s wear coefficient. By applying this coefficient into the numerical simulation of wear, it is possible to predict wear without long lasting and usually expensive experiments.

To determine necessary particles of Archard’s equation and calculate wear coefficient K, an experimental investigation is proposed. Afterwards, the wear simulation is executed in FEM software ANSYS 18.1. Analytical method is offered to determine worn volume for cylinder-in-cylinder contact, based on “inclination” of inner cylinder.

Comparing the value of Archard’s coefficient obtained by this experimental investigation with the values from the literature for the similar materials, high correlation is noted. Furthermore, numerically calculated contact pressure is confirmed with analytical method. Trend of pressure decrease due to wearing process, as well as due to increase of contact surface is observed.

Since the prediction of the wear is closely related to the life cycle assessment of bearings, and the machines in general, it has significant practical importance for designers.

Determination of Archard’s coefficient is usually performed by conventional pin-on-disk tribometers. This methodology offers a different approach for the determination of Archard’s wear coefficient for cylinder-in-cylinder contact, which is convenient for shaft-sliding bearing contact.

Oblique impacts which occur in many situations in mineral industries leads to material removal and fail of mechanical parts. Studies will be helpful in optimal design to have minimum machine malfunctions.

In the present work, the Hertz-Di Maio Di Renzo nonlinear model of contact is used to simulate the impact phenomenon as a micro-sliding process. The modified Archard equation is used to evaluate wear over the impact. The wear coefficient is evaluated by a pin-disk machine. An impact-wear tester is used to validate the model results.

The measurements indicate an increase in surface hardness because of the several impacts. It is considered in the wear predictive model.

The model predictions compared with the experimental data, obtained from the impact-wear tester, show that the model well predicts the impact wear and can be used as a predictive tool to study the practical design problems and to explain some phenomena associated with the percussive impact.

The purpose of this paper is to use a wear test to determine the effect of sand on the wear rates of materials typically used in aerospace applications. Once a repeatable wear test has been established, it can be used to test any combination of materials or coatings. The effectiveness of several different test methods will also be evaluated, including the sample height, surface roughness and mass difference. In addition, the current work will observe the differences between applying sand before the samples are brought into contact or after. The wear rates obtained from these tests could also be used to predict the wear of other components in similar abrasive particulate environments.

A modified block-on-flat wear test of anodized aluminum on hard coat anodized aluminum was used to study this. The experiments were performed with and without sand to study the effects of the sand. Two methods of adding sand were also evaluated. Weighing and profilometry were used to study the differences between the tests.

Wear rates have been calculated based on both the change in the masses of the samples and the change in the height between the upper and lower samples over the course of each test. The wear rates from the change in the masses are repeatable with and without sand, but the results for the change in height show no repeatability without sand. In addition, only in the presence of sand do the trends for the two methods agree. The wear rate was found to be non-linear as a function of load and therefore not in agreement with Archard’s Wear Law. The wear rate also increased significantly when sand was present in the contact for the duration of the test. The sand appears to change the wear mechanism from an adhesive to an abrasive mechanism. Black wear particles formed both when there was sand and when there was not sand. The source of these particles has been investigated but not determined.

This work has not been previously published and is the original work of the authors.

The misaligned condition in splines coupling brings more relative motion between the engaging tooth surface and subsequently a rise of wear phenomenon. The sliding friction between the spline surfaces and initial gap between the teeth are the key roles in wear behaviour in both crowned and straight splines. The paper aims to discuss these issues.

There is a design constraint to include fretting and wear damage of spline surface in design criteria. It becomes very essential to use a finite element tool to evaluate the wear behaviour of spline surface in order to design for severe environmental conditions. The fretting fatigue and fretting wear damage mechanisms on the spline surfaces are mainly dependent on the forces between the spline surfaces and relative movement between the teeth. This study focusses on the effect of sliding friction coefficients on the wear damage of the spline surfaces based on mating condition.

Analysis shows that the contact pressure and root stress increase with increasing friction coefficient and misalignment. This is irrelevant to the crowned type of splines. This case becomes worst when the spline has more misaligned condition.

The fretting wear damage of straight spline is essential criterial for the application in aero engines and the crowned spline under controlled misaligned condition provides better wear life compared to straight spline surfaces.

Since the middle of the 1970s, lubrication of the high rail flange has been used to reduce wear rates. Field tests have been taking place since 1997 to evaluate the differences in wear characteristics between mineral oil based grease and new environmentally adapted greases. The field tests have also investigated whether the addition of graphite contributed to reduced flange wear. The wear reducing effect of trackside lubrication as a function of distance from point of application of the grease was also investigated. The field tests showed that environmentally adapted greases can be used without risk of increased rail wear and that the addition of solid lubricants, such as graphite, has no significant effect on the rate of wear. The highest wear rates were found during winter months when active lubrication stops due to problems associated with the sub‐zero temperatures common in northern Sweden. Year‐round lubrication would be expected to decrease wear rates significantly.

The paper aims to examine the mechanical and wear performance of A356/Al₂O₃ (alumina) nanocomposites. The correlation between wear performance and the microstructural properties that result from various mechanical milling periods was investigated.

The production of nano alumina reinforced (1 Wt.%) A356 aluminum nanocomposite specimens was carried out using the traditional powder metallurgy method, incorporating three different mechanical milling times (1, 2 and 4 h). Subsequently, mechanical and wear performance assessments were conducted using hardness, compression and pin-on-disc wear tests.

Although the specimens subjected to the most prolonged mechanical milling (4 h) demonstrated superior hardness and compressive strength properties, they exhibited a remarkable weight loss during the wear tests. The traditional evaluation, which supports that the wear performance is generally correlated with hardness, does not consider the microstructural properties. Since the sample milled for 1 h has a moderate microstructure, it showed better wear performance than the sample with higher hardness.

The originality of the paper is demonstrated through its evaluation of wear performance, incorporating not only hardness but also the consideration of microstructural properties resulted from mechanical milling.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-02-2023-0031/

Fretting wear exists widely in the field of matching mechanical parts whereas previous research studies mostly focus on the point contact through a ball-plate tribometer. This paper aims to study the influence of wear debris on the fretting wear characteristics of the nitrided medium carbon steel under line contact condition at elevated temperature.

Fretting wear behavior of the nitrided medium carbon steel was experimentally investigated under line contact condition at elevated temperature and different normal loads without lubrication. Wear loss, worn surface and wear debris were studied to analyze the wear mechanism of nitrided steel.

The results showed that surface hardness of the medium carbon steel was notably improved because of the generation of a 230 µm nitrided case. Wear loss increased with the normal load, which was associated with the damage of a thin solid film formed by the wear debris, consisting of iron oxides and chromium oxide rather than only iron or iron oxides. The wear debris became partially amorphous and spherical because it was trapped within the contact interface and was ground, rolled, oxidized under line contact conditions. The spherical wear debris acted as a third body and formed a lubricating film between the contact faces. This lubricating film helped to stabilize the friction coefficient and reduced the wear rate, which further caused the acceleration of wear volume to gradually decrease. The wear mechanisms of the nitrided steel were oxidation wear, abrasive wear and fatigue spalling of the oxide layer.

The findings are helpful to understand the fretting wear behavior of the friction pair under line contact and enrich the fretting tribology theory.

The purpose of this paper is to investigate applicability of hexagonal boron nitride (h-BN) powder as a solid lubricant additive in coconut oil and to determine the tribological behavior of PEEK rubbed with DIN2080 tool steel, under prepared green lubricating condition.

In this study, tiribological performance of PEEK against the DIN2080 tool steel is investigated with green lubricant. Coconut oil was used as green lubricant and 4 per cent wt. h-BN powder was added as lubricant additive into the coconut oil. Reciprocal pin-plate tribological test were applied under dry, coconut oil and coconut oil+h-BN lubrication condition. Friction coefficients were recorded and wear behavior of the samples investigated by mass loss measurement and topographical inspection of wear track by optical profilometer.

Using coconut oil as lubricant provided 80 per cent reduction of friction coefficient and 33.4 per cent reduction of wear rate. Addition of h-BN into the coconut oil provide 84 per cent reduction of friction coefficient and 56 per cent reduction of wear rate. The results showed that vegetable oil is promising lubricant for sustainable manufacturing. h-BN serves to increase lubricant performance and decrease wear of the surfaces.

Petrochemical lubricants are one of the major sources of environmental pollution and health hazards. Development and use of environmental and health friendly lubricants support sustainability and reduce wear, friction and energy consumption. With this consciousness, recent studies have focused on green tribology and green lubricants such as vegetable oils, ionic liquid bio-lubricants and bio-based polymers.

In literature study coconut oil was proposed as green lubricant while h-BN powder was proposed as solid lubricant. However, applicability of h-BN powder in coconut oil has not been explored yet. Moreover, wear and friction property of PEEK material with DIN 2080 tool steel pair surface has not been studied yet with green lubricants.

FeNi36 (Invar-36) alloy is widely used in the fabrication of molding tools in aerospace industries but there remains a need to improve its wear and friction performance due to its relatively low hardness. The formation of a heat affected zone (HAZ) on the surface of Invar-36 cut by wire electric discharge machining (WEDM) is promising to enhance its tribological properties. This study aims to investigate the tribological performance of WEDM-treated Invar-36 via a ball-on-disk tribometer in dry-sliding conditions.

The untreated and WEDM-treated Invar-36 surfaces were reciprocated against an alumina ball at a sliding velocity of 40 mm/s, a stroke length of 10 mm and a sliding duration of 125 min under loads of 5, 10 and 20 N. The worn surfaces were characterized using a 2D profilometry and a scanning electron microscope equipped with energy-dispersive spectroscopy.

The results showed that the WEDM-treated surface had a superior friction coefficient and wear resistance in comparison to the untreated surface, due to the grown HAZ. There was found to be a 9.3%–11.4% decrease in the friction coefficient and a 47%–57% reduction in the wear volume after the WEDM treatment. Both the untreated and WEDM-treated Invar-36 surfaces found abrasion and plastic deformation as the dominant wear mechanisms.

Previous works have not focused on the tribological performance of the WEDM-treated Invar-36 extensively used for molding tools in aerospace industries. Our findings provide compelling evidence that the WEDM treatment improved the wear and friction performance of Invar-36 alloy because of the grown HAZ.

To design and fabricate a wear testing rig for a water pump impeller and to select a parameter that can be used to determine the wear rates of slurry pump impeller.

A wear equipment was designed and fabricated in this study that of main rotating shaft, supported by two ball bearings, and main electric motor bully mechanism for the rotational speed torque needed. An impeller made of cast iron was selected. The wear medium selected consists of solid particles and water. The tests were conducted by letting the impeller to rotate in slurry. The wear data collection are divided into impeller's weight loss, impeller's diameter loss, impeller blade's thickness loss, impeller's blade height loss and impeller's thickness change.

The major type of wear that takes place in this experiment is erosion. The weight loss of the impeller is due to the material removal from the impeller as result of erosion wear. The diameter loss of the impeller is attributed to the impingement of solid particles on the surface area. The surface topography under the microscope indicates that the region near the center of impeller encounters less wear compared to the region at the rim of the impeller.

From this study, among all the parameters studied, the height loss of impeller blades encounters the highest percentage of wear. This is useful for determining the running hours before the complete failure of the impeller for slurry and impeller types used in this study.