-
-
PVD coated dies in action: Exploring finite element analyses for sheet metal forming of high‐strength steel Lubr. Sci. (IF 1.9) Pub Date : 2024-02-28 S. Sivarajan, Diogo M. Neto, Marta C. Oliveira, Padmanabhan Raghupathy, Luis F. Menezes
This research proposes a complete analysis of the use of physical vapour deposition coated dies in the sheet metal forming process for high‐strength‐steel sheets. The goal of the proposed approach is to investigate how PVD coatings affect die performance and how that affects the formability and quality of the high‐strength‐steel‐sheets that are made. The finite element analyses are used to simulate
-
Research on the lubrication performance of circular tilting pad thrust bearings for large wind turbines Lubr. Sci. (IF 1.9) Pub Date : 2024-02-21 Jianlei Wang, Yang Cao, Wenye Sun, Runlin Chen, Qian Jia, Yahui Cui
In view of the large temperature rise and impact load of thrust bearings in the main shaft system of large wind turbines, this article takes the circular tilting pad thrust bearings in large wind turbines as the research object, and analyses the basic theory of bearing lubrication. The lubrication performance calculation model established for this bearing includes the Reynolds equation, energy equation
-
Coupling effect of partial composite texture and thermal effect on the performance of hydrostatic bearing Lubr. Sci. (IF 1.9) Pub Date : 2024-02-21 Dongju Chen, Yu Cui, Kun Sun, Jinwei Fan, Kai Cheng
This work is focused on performance computation of high speed rotor bearing system with partial composite texture. Since its viscosity at varying speeds affects working performance in different partial composite texture, therefore at design and development stage, it is necessary to know the composite texture and thermal effect acting on rotor‐bearing system that causes variation of performance. The
-
Parameter design and dynamic stability of controllable damping ferrofluid bearing Lubr. Sci. (IF 1.9) Pub Date : 2024-02-16 Xuhui Liu, Wenqiang Xu, Huina Hu, Yan Wu, Pianpian Yan, Bin Xu
The purpose of this paper is to carry out parameter design and dynamic stability verification experiment of controllable damping ferrofluid bearing. A new type of ferrofluid bearings is designed, and its internal magnetic fields are simulated by the finite element analysis software ANSYS. In this paper, the coefficient of magnetic leakage is taken as the optimization object, and the optimal parameters
-
Tribological properties of a novel iron-based self-lubricating composite Lubr. Sci. (IF 1.9) Pub Date : 2024-02-05 Chen Zhu, Ilhoon Ahn, Xiaojing Zheng, Yichen Bao, Yinghui Dong, Lulu Yao, Ruhong Song, Daogao Wei, Yufu Xu
In this work, the tribological properties of a novel iron-based self-lubricating composite as the tribopairs of a plunger pump were systematically studied on an end-face tribometer, and the tribological mechanism was also revealed. The results show that the wear mechanism of the composite can be ascribed to adhesive wear when the sliding speed is lower than 1.5 m/s. As the sliding speed increases from
-
Simulation study on the performance of gap oil film lubrication under extreme working conditions of micro-textured hydrostatic support Lubr. Sci. (IF 1.9) Pub Date : 2024-02-06 Yanan Feng, Xiaodong Yu, Hui Jiang, Ruichun Dai, Wentao Jia, Junfeng Wang, Jianhua Jiao
Based on the theory of fluid mechanics, the lubrication performance of micro-textured hydrostatic bearings is derived. Under extreme operating conditions, the lubrication performance of clearance oil film without micro-texture and with rectangular and triangular micro-textures added to the oil sealing edge is simulated, and the experimental verification of the lubrication performance of the double
-
Effect of cutting and feed speed on lubrication performance of large hydrostatic turntable with constant linear velocity Lubr. Sci. (IF 1.9) Pub Date : 2024-01-25 Zhang Yanqin, Zhao Rong, Tao Jianting, Wang Mulan, Kong Pengrui
The oil film lubrication performance of a large hydrostatic turntable operating at the model of constant surface cutting speed is studied. Firstly, the rotary speed equation which is bound by the constant surface cutting speed is established. According to the fluid lubrication theory, the gap flow equation, the oil film temperature rise equation and the double-rectangular-cavity oil pad bearing capacity
-
Investigation of tribological properties of MoS2 and CaF2 particles as oil additives and their effects on surface contact Lubr. Sci. (IF 1.9) Pub Date : 2024-01-25 Hasan Baş, Muhammet Ali Beşirbeyoğlu, Onur Özen
Nowadays, researches on the use of alkali metal salts as friction-reducing and anti-wear oil additives are continuing. In this study, the tribological effects of heavy metal containing MoS2 and alkali metal salt CaF2 additives on pure engine oil (20W50) were investigated using block-on-ring tester configured as surface contact geometry. The tests were performed at various contact loads, revolutions
-
A new efficient flow continuity lubrication model for the cylinder liner-piston ring based on the locally oriented roughness Lubr. Sci. (IF 1.9) Pub Date : 2024-01-18 Wen-Bin Chen, De-Liang Liu, Jiu-Jun Xu
The locally oriented roughness is a common feature of surface finished by a machining process, such as the surface of the cylinder liner, and may significantly influence lubrication characteristic. A homogenised transient Reynolds equation for the locally oriented roughness is derived. The Jacobsson–Floberg–Olsson (JFO) boundary conditions was implicitly incorporated into the transient Reynolds equation
-
Effect of different base oils on the friction behaviour of polycrystalline diamond compact Lubr. Sci. (IF 1.9) Pub Date : 2024-01-14 Ruyi Gou, Jingjing Chen, Xun Luo
This study analysed and discussed the friction and wear properties, as well as the interface evolution behaviour of polycrystalline diamond compact (PDC) under various base oils, through conducting friction experiments on PDC/Si3N4 with different base oils. The friction and lubrication mechanism of PDC under different base oils were examined using scanning electron microscopy (SEM), x-ray energy dispersive
-
Research on the cavitation characteristics and structural optimisation of spiral grooved thrust bearing lubricated by liquid hydrogen Lubr. Sci. (IF 1.9) Pub Date : 2024-01-07 Shaohang Yan, Tianwei Lai, Mingchen Qiang, Qi Zhao, Wenjing Ding, Yutao Liu, Yu Hou
In liquid hydrogen (LH2) delivery, submersible centrifugal pump is an important device. Its reliability and efficiency rely on the stability of the bearings. In a high-speed range, cavitation occurs due to the hydrodynamic effect induced pressure undulation. Compared with other cryogenic fluids, cavitation in LH2 is prone to happen due to its special properties. In this paper, a cavitation model considering
-
Numerical study on the churning power loss of spiral bevel gears at splash lubrication system Lubr. Sci. (IF 1.9) Pub Date : 2024-01-07 Shuai Hu, Wuqi Gong, Peng Gui
In order to predict the spiral bevel gear churning power loss, based on the Computational Fluid Dynamics (CFD) method, the computational model for the splash lubrication of the spiral bevel gear pair is established and validated by experiments. The churning power loss of spiral bevel gears is obtained and the corresponding flow field distribution in the gearbox with a pair of spiral bevel gears is
-
Laboratory measuring of contact angles for liquid/solid surface and analysis with artificial neural network Lubr. Sci. (IF 1.9) Pub Date : 2024-01-07 Sajad Jaberi, Gholamreza Moradi, Seyed Ali Alavi Fazel
In this study, the advancing and receding contact angles of three types of pure liquid on four different surfaces have been measured. The contact angles of the droplet have been measured by analysing the captured photo by tilted plate method. Droplet behaviour has been modelled by two experimental equations. Additionally, the data has been modelled by an artificial neural network using genetic algorithm
-
Effect of partial surface waviness on the dynamic and stability performance of journal bearing Lubr. Sci. (IF 1.9) Pub Date : 2024-01-03 Arun Bangotra, Sanjay Sharma
This study presents the impact of full and partial surface waviness on the dynamic and stability performance of the journal bearing. The Reynolds equation is modified to account for the impact of surface waviness, and the lubricant domain is discretized using the Finite element method to obtain dynamic characteristics such as stiffness and damping coefficients and stability parameters, that is, threshold
-
An enhanced technique for friction stir welding of ceramic particle reinforced aluminium based metal matrix composites Lubr. Sci. (IF 1.9) Pub Date : 2024-01-02 Paneerselvam Natarajan, Sekar Tamilperuvalathan, Vijayakumar Murugesan, Kumaresan Govindasamy
This manuscript proposes an enhanced technique for the friction stir welding (FSW) of ceramic particle-reinforced aluminium-related metal matrix composites. The proposed technique is the joint implementation of both the Aquila Optimizer and Pelican Optimization Algorithm. This proposed method aims is to enhance the welding efficiency, quality, and overall performance of the weld joints. The test is
-
Study on the solution algorithm of Reynolds equation of self-acting gas journal bearings based on a finite difference method Lubr. Sci. (IF 1.9) Pub Date : 2024-01-04 Zhang Haijun, Yang Qin, Zhao Wei, Jiang Feilong
It is very crucial to solve the Reynolds equation quickly and accurately using the numerical methods in the research field of fluid lubrication. For the static Reynolds equation of self-acting gas journal bearings, the typical solution algorithm of the finite difference method is put forward and a new solution algorithm of the finite difference method is proposed. Secondly, the Reynolds equation is
-
Research on internal two-phase flow in the local micro-clearance design of a high-speed ball bearing with under-race lubrication Lubr. Sci. (IF 1.9) Pub Date : 2024-01-03 Ping Gong, Zhenxia Liu, Qingjie Yu, Fei Chen
In this research, an angular contact ball bearing with two-half inner rings is used as a carrier. Considering the two-phase flow characteristics of oil and air in the bearing, the flow characteristics of lubricating oil inside the bearing with under-race lubrication are studied. Based on the volume of fluid (VOF) method and the standard k–ε turbulent flow model, the characteristics of oil and air two-phase
-
Flow field analysis and structure optimization of liquid sodium hybrid bearing Lubr. Sci. (IF 1.9) Pub Date : 2024-01-02 Fei Song, Xuefeng Yang, Zhiqiang Zhang, Wenlong Dong, Min Wu, Zhiyuan Wang, Yeqi Zhu
Liquid sodium hybrid bearing is mechanical pump shaft bottom key support components, that play a balanced radial force of the impeller by fluid effect, in order to improve the bearing performance, based on the calculation model, simulation analysis, structure improvement and other aspects of analysis, this paper based on the theory of fluid mechanics of bearing finite element model for numerical calculation
-
Nanoparticles encapsulated carbon nanotubes dispersed lubricants for enhanced tribology through particle-phase variation Lubr. Sci. (IF 1.9) Pub Date : 2023-12-29 Nisha Ranjan, Muthusamy Kamaraj, Sundara Ramaprabhu
Nanostructures as an inert additive to the lubricant act as a tiny friction reduction element by providing asperity filling, polishing, and film formation mechanism at the nanoscale dimension under the boundary layer regime. Here, we explore the synthesis and tribology application of iron-carbon-based nanoparticles encapsulated multiwall carbon nanotubes (Fe-C-CNTs). Three Fe-C nanoparticles phase
-
Laser surface textures enhance the friction and wear behaviour of orthodontic brackets Lubr. Sci. (IF 1.9) Pub Date : 2023-12-25 Kai Zhou, Zonglin Pan, Xin Luo, Ping Yang, Pengfei Wang
Minimising the friction force of the archwire-bracket sliding contact is crucial for achieving a high-quality orthodontic treatment. Micro-dimples and micro-grooves textures were successfully produced on the two slot surfaces of the stainless steel orthodontic brackets with the laser surface texturing technology. The effect of surface texture on reducing the friction and wear behaviour of the stainless
-
Tribological performance of polymeric friction modifiers under sliding rolling contact condition Lubr. Sci. (IF 1.9) Pub Date : 2023-10-03 Febin Cyriac, Xin Yi Tee, Pui Shan Chow
The tribological performance of two polymeric friction modifiers, one based on an ester-based compound and another based on an ethoxylated fatty ester and an organic friction modifier, oleamide, was studied at 50, 90 and 140°C using a Mini Traction Machine equipped with optical interferometry and electrical contact resistance. The ability to form surface film is found to vary among the friction modifiers
-
Isopropyl-branched lard and its potential application as a bio-based lubricant Lubr. Sci. (IF 1.9) Pub Date : 2023-09-20 Hailemichael O. Yosief, Majher I. Sarker, Grigor B. Bantchev, Robert O. Dunn
Regular lard (RL) was chemically modified into isopropyl-branched lard (BL). The isopropyl group was introduced into the triglyceride structure via a reaction of carbon–carbon double with isopropyl bromide in presence of ethylaluminum sesquichloride. The reaction was confirmed with gas chromatography–mass spectroscopy, nuclear magnetic resonance, infrared spectroscopy. The physical, tribological and
-
Numerical investigation of wheel-rail adhesion using a simplified three-dimensional model considering surface roughness and temperature Lubr. Sci. (IF 1.9) Pub Date : 2023-09-17 Jiaqing Huang, Bing Wu, Guangwen Xiao, Quan Shen
Wheel-rail adhesion is important to the traction and braking of railway vehicles. This paper develops a three-dimensional numerical model considering surface roughness and temperature to investigate water-contaminated adhesion characteristics. A simplified elastohydrodynamic lubrication model considering the thermal effect is developed to obtain the normal load carried by liquid film and asperities
-
Experimental investigation to assess the effect of graphene blended lithium grease on friction, wear, and surface morphology of 52100 chrome alloy steel contacts Lubr. Sci. (IF 1.9) Pub Date : 2023-09-13 Deepak Kumar Prasad, Santhosh Kumar Kamarapu, Neeraj Kumar Bhoi, M. Amarnath, H. Chelladurai
The results of a research on the tribological behaviour of lithium grease with the addition of graphene nanoparticles are presented in current work. Using a four-ball tribometer, the wear and friction coefficient of lithium grease and blended grease samples with graphene additions were assessed. The significance of graphene in enhancing the tribological properties of grease materials is evident from
-
The size effect of typical micro- and nano-calcium carbonate additives on the friction properties of calcium sulfonate grease Lubr. Sci. (IF 1.9) Pub Date : 2023-09-13 Longqi Sun, Qin Zhao, Rui Ma, Huaigang Su, Gaiqing Zhao, Xiaobo Wang
This paper firstly reports the size effect of typical micro- and nano- calcium carbonate additives on the friction properties of calcium sulfonate grease. The rheological and tribological performance of calcium sulfonate grease with typical micro- and nano- calcium carbonate additives were investigated at 30 or 80°C by Rheometer and Optimol SRV-V tester. To its surprise, calcium sulfonate grease with
-
Study on mixed elastohydrodynamic lubrication performance of point contact with non-Gaussian rough surface Lubr. Sci. (IF 1.9) Pub Date : 2023-09-12 Hongjuan Hou, Jiaxing Pei, Dongxing Cao, Leilei Wang
A numerical method is proposed to evaluate the effect of non-Gaussian roughness on point contact elastohydrodynamic lubrication (EHL). A mixed EHL model of point contact, considering non-Gaussian roughness, is developed. The oil film pressure in the model was controlled by the Reynolds equation of average flow, and the contact pressure of asperity was obtained by the rough surface micro-contact model
-
Grease material properties from first principles thermodynamics Lubr. Sci. (IF 1.9) Pub Date : 2023-07-29 Jude A. Osara, Sathwik Chatra, Piet M. Lugt
Thermodynamics has historically been used to derive characteristic material properties. In this study, fundamental thermodynamics is applied to grease. First-principle formulations of existing material properties—heat capacity and storage modulus—and new properties—thermal strain and stress coefficients, chemical resistance and thermo-chemical decay coefficient—are derived, some of which are experimentally
-
Structural characterisation of iron sulfide tribofilms formed on carbon and stainless steels Lubr. Sci. (IF 1.9) Pub Date : 2023-07-21 Makoto Miyajima, Mitsuharu Yonemura, Kazuyuki Kitamura, Keishi Matsumoto, Kazuyuki Yagi
This study investigated tribofilm layers formed under boundary lubrication using a polysulfide additive on S45C and SUS304 steel surfaces. In the tribotests, the friction coefficient of the SUS304 disc fluctuated and increased more gradually in comparison to that of the S45C disc. The tribofilm on the S45C disc comprised the outermost and inner layers of FeS2 (pyrite) and FeS (troilite), respectively
-
Study on mechanical characteristic of angular contact ball bearing with local defects under elastohydrodynamic lubrication Lubr. Sci. (IF 1.9) Pub Date : 2023-07-20 Kai Liu, Chunli Lei, Ruizhe Song, Wei Xue, Jianhua Li
The elastohydrodynamic lubrication (EHL) model of angular contact ball bearings (ACBB) with local defects under spin condition is established. The local defect surface profile is characterised. On this basis, the modified quasi-static model of ACBB with local defects is proposed. Then, the comprehensive stiffness model of ACBB with local defect under EHL is built, and the influence of different factors
-
Wear resistance by copolymers with controlled structure under boundary lubrication conditions Lubr. Sci. (IF 1.9) Pub Date : 2023-07-19 T. Omiya, F. De Bon, T. Vuchkov, A. C. Serra, A. Cavaleiro, J. F. J. Coelho, F. Ferreira
Lubricants are of paramount importance in protecting metallic contact surfaces and reducing friction. The viscosity of lubricating oil can be engineered by introducing long linear polymers, such as poly(lauryl methacrylate) (PLMA). In particular, the formation of adsorption films by using polymers with hydroxy or amino side groups has attracted much attention in recent years. In this study, copolymers
-
Tribological characteristics evaluation of a helical gear pair based on the tribo-dynamic model Lubr. Sci. (IF 1.9) Pub Date : 2023-07-19 Mingyong Liu, Xinguang Han, Chunai Yan, Zhouhuan Ouyang, Dezhong Qi
In this paper, a tribo-dynamic model of a helical gear is established. For the lubrication sub-model, a finite line thermal elastohydrodynamic lubrication model of helical gear is adopted. The lateral vibration, axial vibration of gear and torsional vibration of the gear shaft are considered in the dynamic sub-model. Results show that the tribological parameters of helical gear under the tribo-dynamic
-
Research on characteristics of splash lubrication and power losses of reducer based on MPS method Lubr. Sci. (IF 1.9) Pub Date : 2023-06-14 Huanlong Liu, Tao Wei, Jianyi Zhou, Chixin Xie
The distribution of lubricant flow field inside the two-stage transmission reducer is very complicated during splash lubrication, which is difficult to be visually simulated and analysed using traditional finite element methods (FEM). There are many problems in model processing, algorithm selection, mesh division, and computational workload. Through sufficient investigation and experimental validation
-
Effect of sliding speed on the thermohydrodynamic performance of partially slip-textured slider bearings Lubr. Sci. (IF 1.9) Pub Date : 2023-05-21 Sartaj Singh, Saurabh Kango
The present study evaluates the combined use of micro-textures and ‘wettability gradient’ on the thermohydrodynamic performance of inclined slider bearings. Mass conserving Elrod cavitation model with slip boundary condition has been used to investigate the dimensionless static performance parameters at different convergence ratios and sliding speeds. The most effective location of the wettability
-
Structure design and sealing performance analysis of the sealing mechanism of the drilling tractor Lubr. Sci. (IF 1.9) Pub Date : 2023-05-17 Jianguo Zhao, Ju Wang, Guorong Wang, Qingyou Liu, Ying Zhang
In order to ensure the reliability of drilling tractor in the downhole operation, three high-temperature and high-pressure sealing mechanisms are designed in this paper to balance the pressure difference between the inside and outside of the drilling tractor, namely the triangular, the U-shaped and the right-angle combined sealing structure. In this paper, three models of combined sealing structures
-
Tribological evaluation of PAO 100 oil-based lithium greases with chemically functionalized nanoadditives Lubr. Sci. (IF 1.9) Pub Date : 2023-05-08 Homender Kumar, Harsha A. P., Sooraj Singh Rawat
The lubricating greases employed in this study were formulated with polyalphaolefin (PAO) 100 as the base oil and 12-lithium hydroxystearate as the thickener. The sol–gel method was used to produce the LaF3 nanoadditives. The oleic acid-treated LaF3 (i.e., OA-LaF3) and carboxylic acid-treated MWCNTs (i.e., COOH-MWCNTs) were blended in the formulated grease samples and used as nanoadditives. The detailed
-
Improvement of tribological properties of water-based ZnO nanoparticles lubricant for zirconium alloy cold rolling by hydroxyethyl cellulose Lubr. Sci. (IF 1.9) Pub Date : 2023-05-04 Qi Liu, Jing Li, Junfeng Zhang, Hengdi Yuan, Ange Nsilani Kouediatouka, Guangneng Dong
Currently, substantial adhesion wear frequently occurs in Zr alloy cold rolling, which not only affects the quality of product's surface, but shortens the mould's service life. In this paper, water-based lubricant was prepared by using ZnO as additive and hydroxyethyl cellulose (HEC) as dispersant. The tribological test results showed the friction coefficient decreased by a maximum of 84.6%, and the
-
Role of ZnO/MWCNTs hybrids nanoparticles addition on the tribological behaviour of SN150 paraffinic mineral oil Lubr. Sci. (IF 1.9) Pub Date : 2023-05-02 K. Asraf Rahim, Safaa N. Saud, Y. C. Wee
Nanoparticle incorporation plays an active feature in heat transfer, ultimately enhancing the tribological process under boundary conditions of heat stress. Nanoparticles like zinc oxide (ZnO) and multiwall carbon nanotubes (MWCNT) are well known to significantly affect the cooling and lubrication applications, resulting in improved heat transfer and kinematic viscosity. The present work investigates
-
Formulation and tribological performance of engine oil blended with various non-edible vegetable oils Lubr. Sci. (IF 1.9) Pub Date : 2023-05-02 Juliana Basiron, Mohd Fadzli Bin Abdollah, Muhammad Ilman Hakimi Chua Abdullah, Hilmi Amiruddin
This present study formulated eco-friendly lubricants by combining non-edible vegetable oils with a mineral oil and investigated their efficacy on the friction and wear characteristics of four AISI 52100 chrome steel balls. Multiple formulations containing varying combinations of 0 to 100 vol% of a mineral oil SAE 15W40 (S100), castor oil (C100), and jatropha oil (J100) were prepared using the sonification
-
The influence of local wear and contact roughness on mixed lubrication of marine stern bearing with misaligned shaft Lubr. Sci. (IF 1.9) Pub Date : 2023-05-02 Zeyu Zhao, Qianwen Huang, Minghui Sheng
The marine stern bearing provides supporting force by lubricating film to minimise the contact friction with the propeller shaft. A model considers local wear and asperity contact is proposed to investigate the mixed lubrication of bearing with misalignment. The finite difference method and over-relaxation iteration method are employed to solve the average Reynolds equation. The lubrication behaviour
-
Tribological properties of hexagonal boron nitride nanoparticles as a lubricating grease additive Lubr. Sci. (IF 1.9) Pub Date : 2023-04-28 Yu Cheng, Yingbin Bu, Pengxi Guan, Yujie Yang, Jianbo Qing
The friction and anti-wear behaviours of hexagonal boron nitride (h-BN) nanoparticles as a lithium lubricating grease additive are being investigated under sliding conditions. The grease with 3 wt% 60 nm h-BN particles and the grease with 1 wt% 500 nm h-BN particles lead to 22.34% and 20.18% reductions in the wear scar diameter, respectively, although the friction coefficients slightly decrease. The
-
Experimental and statistical analysis of wear on gear material Lubr. Sci. (IF 1.9) Pub Date : 2023-04-26 Rakesh Ranjan, Santosh Kumar, Subrata Kumar Ghosh, Manoj Kumar
The objective of this paper is to study the parameters that affect the remaining useful life of lubricant (RULL). Fourier-transform infrared spectroscopy (FTIR) of gear oil is used to observe the contamination in the oil. Coefficient of friction (COF) has been found out using pin on disc tribometer using gear oil, and simultaneously, wear debris has been collected. Particles distribution and elemental
-
Enhancement in tribological performance of plastic oil by solid lubricant additives Lubr. Sci. (IF 1.9) Pub Date : 2023-04-24 Soumya Sikdar, Md Hafizur Rahman, Alessandro M. Ralls, Pradeep L. Menezes
In this study, plastic oil (PO) as a potential lubricant was investigated. The base PO was incorporated with graphene nanoplatelets (GNP) and hexagonal boron nitride (hBN) nano additives in varying concentrations to form nano lubricants. Their viscosity, tribological, acidic/basic nature, thermal degradation and dispersion stability properties were investigated. It was observed that 1.5 wt% GNP and
-
A methodology for performance prediction: Hydrodynamic investigation of spiral grooved thrust bearing Lubr. Sci. (IF 1.9) Pub Date : 2023-04-17 Hara Prakash Mishra, Suraj Kumar Behera
This paper presents the design and numerical optimization of oil-lubricated spiral grooved thrust bearing (SGTB) for its application at high speed and axial loading conditions. A numerical model is developed using nonlinear incompressible Reynold's equation and is solved using the finite volume method (FVM) to determine the static characteristics over the bearing surface. Further, the influence of
-
Transient squeezing flow of the lubricant impregnated in the porous material Lubr. Sci. (IF 1.9) Pub Date : 2023-04-15 Guotao Zhang, Liangliang Ma, Ting Jiang, Baohong Tong, Meng Li, Liping Shi
Porous materials are widely used in friction pairs. The transient squeezing flow of the lubricant significantly affects the lubrication quality. The study found that the lubricant penetrates into the porous matrix in the contact area and exudes upward to the entrance of the contact area. The maximum stress occurs at the subsurface of the contact zone, and the maximum pressure occurs at the contact
-
Lubrication performance of GQDs@PNIPAM microgels for titanium alloys Lubr. Sci. (IF 1.9) Pub Date : 2023-03-16 Kang Fu, Kequn Sun, Quan Zheng, Lulu Yao, Ruhong Song, Yufu Xu
The tribological behaviour of YG8-cemented carbide/Ti6Al4V (YG8/TC4) contacts under aqueous lubrication was investigated in this work. Three types of nano-additives including poly (N-isopropylacrylamide) (PNIPAM), graphene quantum dots (GQDs), and GQDs@PNIPAM microgels were prepared for use as water lubricant additives. Tribological tests were conducted at different concentrations of nano-additives
-
Lubrication impact of ferrofluid on cylinder-plate system: A comparative study using two flow models Lubr. Sci. (IF 1.9) Pub Date : 2023-03-01 Rajesh C. Shah
Squeeze-film characteristics between a long cylinder and an infinite flat plate system are analysed. Ferrofluid (FF) lubricant controlled by transverse uniformly strong magnetic field is used for reducing wear and prolonging life of the system. The modified combined Reynolds equation is derived using two different FF flow models (Shliomis and Jenkins), and continuity equation. The expression for dimensionless
-
Detailed tribological analysis of compressor lubricants used in electrical technology Lubr. Sci. (IF 1.9) Pub Date : 2023-02-14 Marina Cardozo Vasco, Laís Pastre Dill, Heloisa Colli Moreira, Daniela Wollmann, Helena Wilhelm, Thiago L. Zanin, Giuseppe Pintaude
This work presents a comprehensive tribological analysis comparing the performance of two types of lubricants—a synthetic and a natural ester—used in industrial reciprocating air compressors. A comprehensive tribological analysis comparing the performance of two types of lubricants—synthetic and natural esters—used in industrial reciprocating air compressors were carried out using surface characterisation
-
Numerical simulation model of reciprocating rod seal systems with axial wear texture on rod surface Lubr. Sci. (IF 1.9) Pub Date : 2023-02-03 Chong Xiang, Fei Guo, Xiaohong Jia, Yuming Wang
In this paper, a simulation model of reciprocating rod seal systems when there is axial texture on the rod surface due to wear is studied. The model includes macroscopic solid mechanics analysis, microscopic contact mechanics analysis and fluid mechanics analysis, and on this basis, the change of surface pressure when the sealing ring fall into a texture is calculated by the micro-deformation mechanics
-
Study on the influence of journal form and position errors on the lubrication performance of four-recess capillary restrictor hybrid journal bearing Lubr. Sci. (IF 1.9) Pub Date : 2023-01-19 Lili Wang, Xue Ge, Jingdong Duan, Longchao Li, Yunlong Bao
In the actual working condition, due to the manufacturing errors, improper installation, load, thermal deformation or other factors can cause the journal surface to produce the form and position errors. The mathematical models are developed that takes into account the form and position errors, the lubrication performance of four-recess capillary restrictor hybrid journal bearings with different journal
-
Forced drop swinging on vibrated and textured metal substrates Lubr. Sci. (IF 1.9) Pub Date : 2023-01-18 Jing Xu, Dongdong Zhou, Jing Ni, Bin Li, Jiadi Lian
A new type of vibrated drop wettability mechanism on a micro-texture surface is proposed and investigated experimentally and theoretically. In this experiment, the mechanical testing machine is used as the vibration source, and the compound control cabinet is used to adjust the vibration liquid feeding table. By comparing the apparent dynamic contact angle, it is concluded that the surface energy of
-
Study the reuse possibility of tempering lubricant for cold-rolled strip wet-rolling processing Lubr. Sci. (IF 1.9) Pub Date : 2023-01-14 Jigang Zhao, Weimin Chen, Junjian Zeng
In the wet rolling process of industrial cold-rolled strips, the tempering lubricant was discarded after one-time use, which resulted in huge waste and high costs for wastewater treatment. In order to explore the reuse value and feasibility of the tempering lubricant, the influences of industrial rolling were to be studied first. In the comparison of before and after-use- tempering lubricant, the surface
-
A study on the lubrication effects of nano-TiO2 additive water-based lubricants during rolling of ferritic stainless steel strips Lubr. Sci. (IF 1.9) Pub Date : 2023-01-13 Xiaoyu Sun, Xiaoguang Ma, Linan Ma, Cunlong Zhou, Jinghui Li, Mingya Zhang, Jingwei Zhao
In the present work, a comparison between traditional oil-in-water (O/W) based lubricant and nano-TiO2 additive water-based lubricants was made to explore the lubrication effects during rolling of ferritic stainless steel (FSS) strips. The results show that marked reduction in rolling force and improvement in the surface quality can be achieved by utilisation of water-based nanolubricant, which can
-
The influence of model organosulfur extreme pressure additives and analogues on the corrosion of copper as measured by a wire corrosion test method Lubr. Sci. (IF 1.9) Pub Date : 2023-01-04 Gregory J. Hunt, Michael P. Gahagan, Mitchell A. Peplow
A wire corrosion test (WCT) is used to investigate the influence of model organosulfur extreme pressure additives and analogues. The corrosion response from these compounds is discussed with regards to chemical structural type. Corrosion rates were calculated using the guide in ASTM G31 to provide a measurement in mm/year.
-
Enhanced ester (MIL-PRF-23699G) gas turbine engine lubricant degradation with VIM VAR M50 bearings Lubr. Sci. (IF 1.9) Pub Date : 2022-12-28 Hitesh K. Trivedi, David T. Gerardi, Douglas K. Toth, Ruth F. Girouard, Patrick T. Hellman, Garry D. Givan
Polyol-ester lubricants have been used and developed for aviation gas turbine engines for many decades. The newest MIL-PRF-23699 lubricant class, called enhanced ester (EE), provides the best combination of thermal stability, load carrying capability, boundary lubrication and compatibility with fluoroelastomer O-rings. Two candidate EE Class formulations and one high thermal stability class formulation
-
Chemically functionalized graphene oxide with N-phenyl-p-phenylenediamine as efficient tribo- and rheological modifier for lubricating oil Lubr. Sci. (IF 1.9) Pub Date : 2022-12-27 Priyanka Agarwal, Suheel K. Porwal, Jyoti Porwal, Raj K. Singh, Naveen Singhal
Nanoadditive with multifunctional properties holds commercial importance in the lubricant industry. Herein, GO-N-PPDA was synthesised as nanoadditive by functionalizing graphene oxide (GO) using N-phenyl-p-phenylenediamine and characterised by Fourier transform infrared spectroscopy, X-ray diffraction analysis, thermogravimetric analysis, scanning electron microscopy and transmission electron microscopy
-
Preparation of graphene-loading copper nanoparticles by freeze drying and its tribological properties Lubr. Sci. (IF 1.9) Pub Date : 2022-12-27 Runling Peng, Wei Wang, Peng Wang, Jinyue Liu, Shijiao Liu, Haonan Zhai, Junde Guo
To reduce the agglomeration of graphene and improve the synergistic friction-reducing and anti-wear action of graphene loading copper, one-step preparation of reduced graphene oxide/copper(RGO/Cu) nanoparticles by freeze-drying method was used, the influence of process parameters on particles size of RGO/Cu is studied by orthogonal experiments. The microstructures of RGO/Cu nanoparticles are characterized
-
Tribological performance of ammonium thiomolybdate as water-soluble lubricant additive for steel-steel contacts Lubr. Sci. (IF 1.9) Pub Date : 2022-12-26 Javier Lara-Romero, Ricardo Rangel, Julián López-Tinoco, Jesús Antonio Carlos-Cornelio, Alejandro Toro-Betancur, Fernando Chiñas-Castillo, Gabriel Alonso-Nuñez, Sergio Jiménez-Sandoval
The friction and wear reducing properties of ammonium thiomolybdate as a water-soluble lubricant additive were evaluated using a pin-on-disck tribometer on a steel-steel contact. The tribological performance of aqueous solutions of thiomolybdate prepared at concentrations between 0.1 and 0.3 wt% Mo were evaluated at the same load (10 N), entrainment speed, sliding distance and temperature. Although
-
Impact of partial surface waviness on the tribological performance of hydrodynamic journal bearing Lubr. Sci. (IF 1.9) Pub Date : 2022-12-04 Arun Bangotra, Sanjay Sharma
In this paper, the static performance analysis of journal bearing having full and partial surface waviness has been presented. The surface waviness is to be considered in the full, first half, second half, and pressure-increasing and decreasing regions of the bearing for analysis. The effect of surface waviness is considered by modifying the lubricant flow governing Reynolds equation with the film
-
Effect of copper nanoparticle concentration on tribological performances of cylinder liner piston ring Lubr. Sci. (IF 1.9) Pub Date : 2022-11-30 Huabing Yin, Xuecheng Zhang, Zhiwei Guo, Zhongzhi Liu, Xiang Rao, Chengqing Yuan
The performance of cylinder liner piston ring (CLPR) that worked under harsh conditions significantly affected the reliability of diesel engines. Nano-copper lubricant additives have recently been introduced due to their good anti-wear properties. This study aims to gain insights into the interactions between concentrations of nano-copper lubricant additives and the tribological performance of CLPR