Purpose The effect of cryogenic heat treatment on the mechanical properties of different materials has been frequently investigated by researchers in recent years. The purpose of this paper is to investigate wear behaviour of monolayer, multilayer and nanocomposite coatings after cryogenic heat treatment. It is a first in its field in terms of both the heat treatment used and the coatings examined

Purpose This paper aims to study the thermal oxidation performance of antioxidant additives in ester base oils deeply. Design/methodology/approach ReaxFF molecular dynamics was used to simulate the thermal oxidation process of butyl octyl diphenylamine and octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propanoate as two antioxidant additives act on the Trimethylolpropane trioleate (TMPTO) base oil

Purpose This paper aims to explore the possibility of converting the nitrile butadiene rubber (NBR) water-lubricated bearing material into a self-lubricating bearing material by the action of polytetrafluoroethylene (PTFE) particles and water lubrication. Design/methodology/approach A group of experimental studies was carried out on a ring-on-block friction test. The physical properties, tribological

Purpose The purpose of this paper is to expound the relationship among microstructure, mechanical property, tribological behavior and deformation mechanism of carburized layer deposited on Ti-6Al-4V alloy by double-glow plasma hydrogen-free carburizing surface technology. Design/methodology/approach Morphologies and phase compositions of the carburized layer were observed by scanning electron microscope

Purpose The exploration of the polar regions is of immeasurable potential. It brings great challenges to tribology in the extreme environment. Moreover, the static friction force is an essential index of the braking performance. The purpose of this paper is the static friction force between the rubber of marine pipe tensioner and the ice bead. Design/methodology/approach The frictional phenomena were

Purpose This paper aims to focus on studying the addition of nano-tungsten disulfide (WS2) on fretting wear performance of ultra-high-molecular-weight-polyethylene (UHMWPE). Design/methodology/approach In this study, the effect of WS2 content on fretting wear performance of UHMWPE was investigated. The fretting wear performance of the UHMWPE and WS2/UHMWPE nanocomposites were evaluated on oscillating

Purpose The purpose of this paper is to examine the effect of surface roughness on the magneto-hydrodynamic (MHD) non-parallel squeeze film lubrication using non-Newtonian lubricant. Design/methodology/approach Based on the MHD thin film lubrication theory and the Stokes theory and homogenization method, the homogenized MHD Reynolds equation is derived considering the squeezing effect. Findings It

Purpose The purpose of this paper is to present the results of a metallurgical, mechanical and tribological characterization of the weld and heat-affected zone (HAZ) of aluminothermic welding of premium rails used in heavy haul, looking into the origins of the squat defects associated with rail wear. Design/methodology/approach A full factorial design of experiment was carried out for 24 welds of premium

Purpose The purpose of this paper is to investigate the optimal design of micro-dimples on the bearing surface of the crankpin bearing (CB) to ameliorate the engine’s lubrication and friction (ELF). Design/methodology/approach A hydrodynamic model of the CB considering the influence of the asperity contact is built under the impact of the dynamic loading of the slider-crank-mechanism. The micro-dimples

Purpose This paper aims to improve the tribological properties of aluminum alloys and reduce their wear rate. Design/methodology/approach Carbon is placed in the model at room temperature, pour 680°C of molten aluminum into the pressure chamber, and then pressed it into the mold containing carbon felt through a die casting machine, and waited for it to cool, which used an injection pressure of 52.8 MPa

Purpose A finite element method (FEM) model of the frictional behavior of two rough surfaces with a group of third-body particles confined by the surface asperities is established. By monitoring the stress distribution, friction force and the displacement of the surfaces, how the frictional instability is induced by these particles is studied. This modeling job aims to explore the relation between

Purpose This paper aims to study the tribological properties of high strength glass fabric/phenolic laminate composites reinforced by carbon fiber (CF) with and without graphene oxide (GO) modified. Design/methodology/approach In this study, the tribological performance tests of the composites were conducted on a block-on-ring tester (MRH-03). The applied load, linear velocity and duration of time

Purpose This study aims to introduce a novel technique which helped in quantifying the wear performance of a roller chain which was lubricated by using the palm oil-based hexagonal boron nitride (hBN) nanoparticles (nano-biolubricant). Design/methodology/approach The efficiency of the nano-biolubricant was evaluated by using a custom-made roller chain tribometer, at different resistance torque values

Purpose The purpose of this study is to reveal the interaction behavior between tubes and supports in steam generators and study the fretting wear of tubes in different load conditions. Design/methodology/approach The fretting wear tests were conducted to investigate the fretting wear behavior of the tubes against three kinds of supports: the drilled circular holes (DCH), anti-vibration bars (AVBs)

Purpose This study aims is to investigate the correlation between tribological and mechanical properties of the fused filament fabrication 3D-printed acrylonitrile butadiene styrene (ABS) pin with different internal geometries. Design/methodology/approach The tribological properties were determined by a dry sliding test with constant test parameters, while the hardness and modulus of elasticity were

Purpose This paper aims to provide thermal elastohydrodynamic lubrication (TEHL) contact model to study all balls’ lubrication performance of the ball screw when the multidirectional load is applied. Design/methodology/approach A new TEHL contact model combining the multidirectional load and the roughness surface texture is established to describe fatigue life of the ball screw. Meanwhile, the authors

Purpose By modeling and analyzing the two-phase mechanical seal of the fan-shaped groove end face, which is prone to phase change, an effective method to study the flow field of the mechanical seal when both cavitation and boiling exist simultaneously is found. Design/methodology/approach Based on the finite volume method, a fluid model was developed to investigate a two-phase mechanical seal. The

Purpose This paper aims to prevent oil starvation and improve the service life of the rolling bearings. Design/methodology/approach A thrust ball bearing with magnetic circuit structure is proposed for ferrofluid lubrication. With the aid of magnetic field, ferrofluid can be maintained in the contact area of rolling bodies to delay lubricant loss. Experiments are performed to ensure the validity of

Purpose The purpose of this paper is to design a biomimetic surface structure for use in a glass transport device to enhance the suspension lift of a glass transport unit. Design/methodology/approach This paper presents a surface structure of a suspended glass transport device based on the principle of bionics. First, a mapping model is constructed based on the wing structure. Second, the optimal structural

Purpose Lithium disilicate glass-ceramics (LS2 GC) are widely used as dental prosthetics and dental restorations. Based LS2 GC have hardness and translucency similar to that of natural teeth. This study aims to investigate the tribological features of LS2 GC with crystalline volume fraction of 64% and different crystal sizes from 8 µm to 34 µm for different counterparts. Design/methodology/approach

Purpose The purpose of this paper is to propose a methodology to quantify the error on wear volume evaluation using optical interferometry with image analysis (OI+IA), to establish a lower threshold for wear mapping in practical applications. Design/methodology/approach A three-dimensional surface wear map is quantified by measuring the same area of a surface before and after a wear process using optical

Purpose This study aims to investigate the friction coefficient of Al2O3–NbC nanocomposite obtained by spark plasma sintering sliding against a steel ball. Design/methodology/approach Tribological tests were carried out using a reciprocating nanotribometer in a ball on flat configuration with normal loads in the range from 10 to 100 mN under dry conditions. Surface changes were analyzed by confocal

Purpose This paper aims to study the influence of thermal effect on the performance for a high-speed conical hybrid bearing including stability and minimum oil film thickness. Design/methodology/approach A thermal hydrodynamic (THD) model and dynamic model of single mass rigid rotor system were established by taking conical hybrid bearing with shallow and deep pockets as the research object, dynamic

Purpose In this study, artificial neural networks (ANNs) are constructed and validated by using the bearing data generated numerically from a thermohydrodynamic (THD) lubrication model. In many tribological simulations, a surrogate model (meta-model) for obtaining a fast solution with sufficient accuracy is highly desired. Design/methodology/approach The THD model is represented by two coupled partial

Purpose The purpose of this paper is to study the effects of operating conditions including process coefficient, lubricant viscosity and cavitation pressure on the cavitation of spiral groove liquid-film seal (SG-LFS). Design/methodology/approach A mathematical model of SG-LFS is established based on the JFO boundary and a relative density is introduced. The universal governing equation after a coordinate

Purpose This paper aims to study the bearing performance with different cone angle errors, to study the effect law of manufacturing taper error on the properties of gas foil conical bearing (GFCB). Design/methodology/approach For the GFCB supported by separated bump foil strips, a nonlinear structure stiffness model considering Coulomb friction and arch characteristics was proposed. The finite element

Purpose Bearings in electric machines often work in high speed, light load and vibration load conditions. The purpose of this paper is to find a new fatigue damage accumulation rating life model of ball bearings, which is expected for calculating fatigue life of ball bearings more accurately under vibration load, especially in high speed and light load conditions. Design/methodology/approach A new

Purpose 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). Design/methodology/approach 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

Purpose The purpose of this paper is to analyze and improve the lubrication performance of a floating cylindrical seal by investigating micro spiral groove. Design/methodology/approach The lubrication model of is solved by finite difference, considering the influence of convergence eccentricity and Rayleigh step on the gas film period. A lubrication model, which is a gas film of floating microgroove

Purpose To improve the lubrication and tribology performance (LTP) of the crankpin bearing, this paper aims to propose the optimization of the crankpin bearing parameters considering effect of the high-speed dynamic load and micro asperity contact. Design/methodology/approach A numerical simulation method combined by the slider-crank-mechanism dynamic and lubrication models is applied to solve the

Purpose The purpose of this paper is to describe the tribological characteristics with different area density of concave-convex micro-texture on the mold surface. It is a new technology to improve the quality of the workpiece to control the tribological properties through the application of concave-convex micro-texture on the mold surface. Design/methodology/approach Five groups of laser micro-texture

Purpose After more than a century of agreement with the postulate of non-slip condition (adhesion to the wall), the study of fluid-solid boundary conditions has shown renewed interest over the past two decades. Although numerous studies have not yet been arrived to a complete description of slip phenomena, however, it appears that the influence of wetting and/or surface roughness results in a weak

Purpose The tribological behavior, i.e. friction coefficient and wear rate, and vibration characteristics of the water-lubricated bearing was investigated. The water-lubricated bearing is made of three different materials, i.e. polyether-ether-ketone (PEEK), polyimide (PI) and nitrile-butadiene rubber (NBR). Design/methodology/approach The tribological behavior was investigated experimentally on a

Purpose This study aims to uncover the influencing mechanism of the tilt angles of the cage pocket walls of the high-speed cylindrical roller bearing on the bearing skidding. Design/methodology/approach A novel cylindrical roller bearing with the beveled cage pockets was proposed. Using the Hertz contact theory and the elastohydrodynamic and hydrodynamic lubrication formulas, the contact models of

Purpose This paper aims to numerically investigate the surface texturing effects on the main bearings of a three-cylinder ethanol engine in terms of the power loss and friction coefficient for dynamic load conditions. Design/methodology/approach The mathematical formulation considers the Partir-Cheng modified Reynolds equation. The mass-conserving Elrod-Adams p-θ model with the JFO approach is used

Purpose This study aims to investigate the influence of surface texture distribution in respect to the procedure of pavement surface wear on friction performance. Design/methodology/approach The Weierstrass–Mandelbrot (W-M) equation is used to appropriate pavement surface profile. Through this approximation, artificial rough profiles by combining fractal parameters and conventional statistical parameters

Purpose This paper aims to investigate the fretting wear mechanism of an Al-Li alloy at room temperature, the tangential fretting wear tests were carried out. Design/methodology/approach The effects of displacement amplitude and fretting frequency on the tangential fretting wear characteristics were mainly investigated. The experimental data obtained are analyzed and compared. Findings The results

Purpose The purpose of this study is to analyze the intelligent fault diagnosis method of rolling bearing. Design/methodology/approach The vibration signal data of rolling bearing has long time series and strong noise interference, which brings great difficulties for the accurate diagnosis of bearing faults. To solve those problems, an intelligent fault diagnosis model based on stacked denoising autoencoder

Purpose The purpose of this paper is to introduce a high-speed rolling bearing test rig supported by sliding bearing and its first experimental results. Design/methodology/approach Through analyzing the disadvantages of using rolling bearing as supporting bearing, the bottlenecks that need to be resolved urgently in the development of rolling bearing experimental technology, and the advantages of the

Purpose As an important part of the rotor system, the damping coefficient of ball bearing has a great influence on the dynamic characteristics of the system. This study aims to propose a theoretical calculation method and an experimental test method to obtain the damping coefficient of ball bearing. Design/methodology/approach Based on Hertzian contact theory and elastohydrodynamic lubrication theory

Purpose Random point-contact between the space bearing retainer and the rolling elements may cause wear of the space bearing retainer. The paper aims to clarify the friction and wear behaviors of polyimide bearing retainer under point-contact condition. Design/methodology/approach Space bearing retainers were cut into flat specimens and the tribological behaviors of the specimens were studied under

Purpose To decrease wear and friction, zinc dialkyldithiophosphate (ZDDP) has been used in engine oil for several decades, but the mechanism of the tribofilm formation is still unclear. The purpose of this study is to characterize the chemical details of the tribofilm by using high-resolution approaching. Design/methodology/approach An ISO VG 100 mineral oil mixed with ZDDP was used in sliding tests

Purpose The purpose of this study is to reveal the tribological performance of the textured rolling bearing. Design/methodology/approach In the present study, the oil film pressure distribution and load capacity analysis method are established, which integrate the micro-texture model and Hydrodynamic lubrication (HL) methods. The tribological performances of the textured rolling bearing under the various

Purpose This paper aims on a methodology to overcome the fact that conventional service life testing of porous journal bearings (PJBs) requires long test times and is not economical. Design/methodology/approach This paper sketches out a pathway to strongly accelerated life tests for PJBs enabled by high load and elevated temperature, which saves months or even years of testing. The testing time is

Purpose The purpose of this paper is to investigate the effect of the cage-pocket wear on the dynamic behavior of the ball bearing. Design/methodology/approach Through analyzing the complicated relationship and interactions among the ball bearing elements, the dynamic modeling of the ball bearing was established considering the gravity, drag force from the oil, hydrodynamic effect on the cage and the

Purpose This paper aims to fabricate nickel-aluminum (Ni-Al)-based self-lubricating composite coating on aluminum (Al) alloy by mechanical milling (MM). Design/methodology/approach A new carrier transport (CT) way was designed to solve the slippage fracture of the coating due to silver (Ag) accumulation (Ag powders were cold welded with nickel [Ni] powders by MM in advance to avoid accumulation, then

Purpose The normal operation of a rotor system is generally vulnerable to misalignment between gas foil bearing (GFB) and rotor. However, most theoretical and experimental researches about the characteristics of GFBs have ignored this phenomenon. Therefore, the main purpose of this paper is to evaluate the static and dynamic performance of GFBs considering misalignment. Design/methodology/approach

Purpose The purpose of this study is to investigate the dynamic behavior of the ball bearing with cage broken. Design/methodology/approach By analyzing the complicated relationship and interactions among the ball bearing elements, the dynamic modelling of the ball bearing with broken cage was established, and the dynamic simulations were conducted by solving the ball bearing dynamic equations using

Purpose The purpose of this paper is to study the effect law of roundness error on the properties of gas foil conical bearing (GFCB), and the performance of bearings with different non-circular sleeve shapes are calculated. Design/methodology/approach For the bump-type GFCB, the nonlinear bump foil stiffness model and 1-D beam top foil stiffness model are built. On this basis, the finite element method

Purpose The serious friction caused by the fluctuation of friction occurs when start-up and will reduce the positioning accuracy of the servo axes of high precision machine tools, the purpose of this paper is to study the friction fluctuation characteristics of friction coefficients between interfaces under different working conditions. Design/methodology/approach HT200 and 45# materials were experimentally

Purpose The purpose of this paper is to clarify the relationship between fatigue life and kinematics of angular contact ball bearing. It proposes a new modeling method of spin to roll ratio based on raceway friction, which is more accurate than the traditional raceway control theory. Design/methodology/approach The uniform model of spin to roll ratio based on raceway friction in a wide speed range

Purpose This paper aims to explore polyaniline (PANI) as a lubricant additive to improve the anti-corrosion and tribological properties of ionic liquids (ILs) for actual applications. Design/methodology/approach ILs were synthesized by dissolving lithium salts in synthetic oil and were used as a base oil to prepare ILs-based greases. PANI was used as an additive. The tribological properties were investigated

Purpose The purpose of this paper is to study the tribology behavior of steel–steel contact under the lubrication of water-based drilling mud with different oleic acid-filled microcapsules as lubricant additives. Design/methodology/approach A ball-on-disc tribometer was used to evaluate the lubrication properties of the steel–steel contact. The wear tracks of the worn surfaces were observed by a scanning

Purpose This study aims to investigate and present the tribological behaviour of recursively friction stir processed 7075 aluminium alloy. Design/methodology/approach In this work, aluminium 7075 alloy is friction stir processed recursively by varying the tool rotational speed, traverse speed and the number of passes. Wear pins for testing were extracted from the processed zone and the surfaces were

Purpose Interactions of different additive types for antiwear/friction modification on surfaces can be synergistic or antagonistic in nature. This paper aims to investigate whether there are interactions between different additives in the adsorption process and whether they synergistic or antagonistic. The yielded correlations will be validated with tribological experiments to answer the question whether

Purpose The purpose of this study is to examine the fretting wear property of ultra-high molecular weight polyethylene (UHMWPE)-based composites reinforced by different content of attapulgite. Design/methodology/approach A series of composites were prepared by a hot-pressing method. Fretting tests were carried out using an SRV-IV oscillating reciprocating friction wear tester with a load of 10 N and

Purpose The purpose of this paper is to enhance film stiffness and control seal leakage of conventional spiral groove dry gas seal (S-DGS) at a high-speed condition by introducing a new type superellipse surface groove. Design/methodology/approach The steady-state performance and dynamic characteristics of superellipse groove dry gas seal and S-DGS are compared numerically at a high-speed condition

Purpose The carbon/carbon (C/C) composite finger seal experiment was performed on a high-speed seal tester. The purpose of this paper is to investigate the leakage and wear characteristics of C/C composite finger seal under various operating conditions. Design/methodology/approach Static, dynamic, endurance and post endurance tests were carried out. For static and performance tests, the pressure differential

Purpose The purpose of this paper is to study the influence of friction coefficient of materials with different elastic modulus on the variation of velocity and load under water lubrication and oil lubrication conditions. Design/methodology/approach Low-viscosity lubricating oil and water were used as lubricants to test the friction performance of the ball-disc contact friction pair in the lubrication

Purpose This study aims to investigate the production and abrasive wear rate of functionally graded TiB2/Al composites. TiB2 particles have been spontaneously formed in liquid matrix using in situ technique. The properties of composites such as hardness, abrasive wear rate and microstructure have been examined. Design/methodology/approach In situ TiB2 reinforcement phase was synthesized by using a