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The study aims to compare tribological properties between laser dimple textured surface and drilled dimple textured surface, and to analyze the influence of dimple hardened edges and ability of trapping wear debris on wear properties of dimple textured surfaces.

Circular textured dimples were produced on AISI 1,045 specimen surfaces using laser surface texturing (LST) and drilled surface texturing (DST) methods. Tribological behaviors of LST, DST and non-textured specimens were studied using ball-on-disc tribo-tester. Metallographic structures, dimples and worn surface morphologies were observed using a three-dimensional digital microscope. Hardnesses of substrate and dimple edges were measured.

There was no obvious difference in wear and friction coefficients between LST and DST specimens. Hardnesses of laser dimple edges were much higher than that of drilled dimple edges and specimen substrate. The hardened materials of laser dimple edge included recast zone and heat affect zone. Laser dimple was cone-shaped and drilled dimple was cylinder-shaped. Drilled dimple had a better ability of trapping wear debris than laser dimple. Non-uniform wear phenomenon occurred on worn surfaces of LST dimple specimens.

The ability of textured dimples to trap wear debris is affected by single dimple volume. Hardened edges of dimples cause non-uniform wear on worn surfaces of LST specimens.

The purpose of this paper is to achieve attractive fabric composites with excellent tribological performance and investigate the wear mechanisms of these fabric composites sliding against bearing steel pins under dry sliding process.

Five different weave density composites were prepared, and the tribological behaviors of these composites were studied at different testing conditions. Scanning electron microscopy, laser microscopy (three-dimensional profile measurements) and energy-dispersive X-ray spectrometry were used to analyze the worn surface morphology, wear volume and elemental content of the transfer films, respectively.

The composite weave density serves an important influence on tribological behavior. Generally, the wear rate of each composite increased with increasing weave density, and the friction coefficient of each composite decreased with increasing weave density.

Nanoparticle-filled hybrid polytetrafluoroethylene/Kevlar fabric composites with proper weave density have exhibited superior tribological properties in dry sliding conditions. The results that obtained in this paper may offer a reference for others who intend to achieve attractive fabric composites with excellent tribological performance.

THIS presentation on fastening of composite structures includes material characteristics, hole generation parameters and methods, types of fasteners available and automation equipment and approaches.

The purpose of this study was to perform a complete experimental assessment of a family of oil ferrous wear debris sensor is performed. The family comprised the original sensor and its re-engineered evolution, which is capable of detecting both amount and size of wear debris particles trapped by the sensor and some predefined oil condition properties.

In this work, the first step was to perform a design of experiments for the sensor validation. A specially defined test rig was implemented, and different ferrous wear debris was collected. For each sensor, two different tests were performed. The first test was called a “void test”, where quantified amounts of debris were collided with the sensor without oil. The second one was a dynamic test, where the sensor was installed in the test rig and different amounts of wear debris were added at a constant rate. In addition, specific tests related with oil properties detection were studied.

The results show excellent correlation of the sensor output signal with the amount of wear debris and a satisfactory detection of debris size in all ranges. Also, the dynamic test presented adequate representativeness, and sensors performed well in this scenario.

This paper shows the practical implementation of this type of sensor and the usual detection range and rate of detection for different debris size and quantities.

This work has a great utility for maintenance managers and equipment designers to fully understand the potential of this type of sensor and its suitability for the application required.

Given the extensive destruction resulting from the devastating 2004 Indian Ocean tsunami that destroyed and damaged resort complexes in southern Thailand, the purpose of this research paper is to focus on the planning of architecture of resorts in two layers: the relationship of structures and land use to the natural environment, and the identification of specific design flaws that resulted in the loss of life.

An international collaborative effort led to site visits by our research team to the hardest‐hit resort areas of Khao Lak, Takua Pa, and Ko Phi Phi on December 29, 2004‐January 6, 2005, and in February 2005. The research team had direct contact with the adverse effects of the tsunami and gained insightful understanding on how structures and faulty architectural designs worsened the disaster and obstructed the process of saving lives. Analysis of these effects were then compiled and used to underpin subsequent proposals for resort reconstruction to minimize future destruction which may result from such calamities.

Close scrutiny and subsequent analysis of various factors which magnified the destruction and damage caused by the tsunami resulted in action plan proposals for sustainable resort development aimed at avoiding a repeat of the tragedy. These include responses to site, architecture, structures, building services and landscaping. More specifically proposals were made on issues of relocation, modifications of design flaws, introduction of escape routes, safer rooms, restoration of waterways, co‐generation, tree plantation and incorporation of natural landscape.

Most of the information and data were gathered first hand at the location mentioned. More studies are needed to reinforce and further validate the proposed measures as generally applicable in similar locations.

An action plan outlining measures aimed at minimizing damage from such natural disasters could provide a useful resource in future planning of resorts in tsunami prone locations.

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 study is to investigate the use of micro-pits technology to the problem of tribological performance in a sliding motion.

Vegetable oil is a sustainable and economically viable alternative to both mineral and synthetic oils, offering significant savings in both the cost of research and manufacturing. To solve the depriving issue and boost lubrication film thickness, the micro-pits on the surface may function as reservoirs that provide the oil to the contact inlet area. In this research, an aluminium block is used as the workpiece material in an evaluation of a through pin-on-disc tribotester. Lubricating oil in the form of super olein (SO) was used in the experiment.

The results show that the friction performance during a rubbing process between a hemispherical pin and an aluminium block lubricated with SO using aluminium alloy materials, AA5083, was significantly improved.

In this study, a material that breaks down called SO, which is derived from the fractionation of palm olein, was used to use a modified aluminium micro-pit sample that will serve as a lubricant reservoir in pin-on-disc tribotester.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2023-0200/

The purpose of this paper is to develop an energy-efficient and dynamically improved thrust ball bearing using textured race. A texture has been used on the stationary race of the test bearing to conduct the long-duration experiment for exploring its tribological and vibrational behaviours under starved lubricating condition using micro size MoS2 blended grease. The performance behaviours of the textured race bearing have been compared with conventional bearing (i.e. having both races without textures) under the identical operating conditions for demonstrating the advantages of textured race.

Texture was created on stationary race of the test ball bearing (51308) using nano-second pulsed Nd: YAG laser. Performance parameters (frictional torque, temperature rise and vibrations) of textured ball bearings were measured under severe starved lubricating conditions for understanding the critical role of texture in the long duration of the test. S-type load cell and miniature accelerometer were used for measuring the frictional torque and vibration, respectively. Bulk temperature at stationary races (at the back side) of test bearings was measured in operating conditions using a non-contact infrared thermometer.

Significant reduction in frictional torque and decrease in amplitude of vibration with textured ball bearing were found even under the severe starved lubricating condition in comparison to conventional bearing.

There is dearth of research pertaining to the performance behaviours of ball bearings using textures on the races. Therefore, an attempt has been made in this study to explore the tribo-dynamic performance behaviours of a thrust ball bearing using a texture on its stationary race under severe starved lubricating condition for the longer duration of the test.

Suggests refurbishment of the many disused public fountains (estimated at up to 2000 in the UK) can be achieved at a fraction of the cost of creating new water displays. Briefly reviews deterioration points – statuary, perimeter walls, pool walls and floor, pumping equipment, pipeworks, pump screens, nozzles and valves, filtration, wind – and water‐controls, winter protection and electrical safety. Concludes that programmed maintenance, and the establishment of specific maintenance responsibility, is crucial for public display fountain operation.

All disasters produce wastes of some kind, be it the trees fallen by a cyclone, a house destroyed by an earthquake, a beach coated by an oil spill, or animals killed by a flood. Postdisaster responses also produce wastes – from the human excreta of people staying in the camp to day-to-day household wastes. The issue of management of wastes created by disasters is becoming an increasingly important issue to be addressed in postdisaster response due to their scale, complexity, and cost. The cost of disaster waste management (DWM) has crossed the billion dollar mark in some of the major disasters, which is necessitating and prompting the emergence of a separate stream of expertise in DWM. In January 2011, the Joint Unit of the United Nations Environment Programme and Office for Coordination of Humanitarian Affairs (OCHA) came out with Disaster Waste Management Guidelines (2011).