Article
Engineering, Mechanical
Daniel Kvarda, Radovan Galas, Milan Omasta, Lu-bing Shi, Haohao Ding, Wen-jian Wang, Ivan Krupka, Martin Hartl
Summary: A numerical model is used to evaluate friction in water-contaminated wheel-rail contact, with the plastic deformation model predicting more accurate transition in mixed lubrication regime.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Engineering, Mechanical
Yuqi Yang, Bing Wu, Guanwen Xiao, Quan Shen
Summary: The purpose of this study is to develop a 3D wheel-rail adhesion model under wet condition, which considers the generated surface roughness topography and the traditional braking procedure for high-speed trains. The results show that the adhesion coefficient of the numerical model is in good agreement with the experimental results. At the instant of braking, the adhesion coefficient drops to a lower adhesion level, especially at a higher speed.
INDUSTRIAL LUBRICATION AND TRIBOLOGY
(2023)
Article
Engineering, Chemical
Jiaqing Huang, Bing Wu, Guangwen Xiao, Quan Shen
Summary: This paper develops a three-dimensional numerical model considering surface roughness and temperature to investigate water-contaminated adhesion characteristics. The model is verified by comparing the results with existing experimental data. The study shows that surface roughness and temperature have significant effects on the adhesion coefficient, and the adhesion-creepage curve is also influenced by temperature.
LUBRICATION SCIENCE
(2023)
Article
Engineering, Mechanical
Mingxue Shen, Bin Rong, Qiuping Li, Meng Yu, Yelong Xiao, Huoping Zhao
Summary: The out-of-roundness of wheel treads is a natural degradation characteristic of railway vehicle wheels. The interface behavior between the wheel and rail caused by out-of-roundness features has significant research value in ensuring high-speed train safety and quality. Testing was conducted to evaluate the effect of out-of-round wheels on wheel-rail damage behavior, and the results showed that eccentric wheels significantly increased the fluctuation amplitude of the wheel-rail vertical force and decreased the adhesion coefficient of the wheel-rail interface. The wear loss of the rail was also accelerated by eccentric wheels, and the surface damage behavior of the eccentric wheels showed non-uniform wear along the circumferential direction.
Article
Mathematics, Interdisciplinary Applications
Sadaf Maramizonouz, Sadegh Nadimi, William A. Skipper, Stephen R. Lewis, Roger Lewis
Summary: The process of applying sand particles to increase traction between wheel and rail is reported to have an efficiency of less than 20%. The Discrete Element Method is used to simulate the process and the results are validated against experimental observations. The simulations confirm that the highest efficiency can be achieved when the sander is aimed at the wheel/rail nip.
COMPUTATIONAL PARTICLE MECHANICS
(2023)
Article
Acoustics
He Ma, Yan Niu, Xiaochun Zou, Jun Zhang
Summary: The wheel-rail adhesion characteristics of high-speed trains are influenced by factors like water, oil, fallen leaves, quartz sand, and their mixtures. Research shows that water, oil, and fallen leaves reduce the maximum friction coefficient, while quartz sand can temporarily increase it but may cause damage if the static friction coefficient is too high. Additionally, both water and oil can enhance the adhesion of quartz sand, with water showing a better effect.
SHOCK AND VIBRATION
(2021)
Article
Engineering, Mechanical
Bingnan Wu, Lubing Shi, Haohao Ding, Jun Guo, Qiyue Liu, Zhongrong Zhou, Roger Lewis, Wenjian Wang
Summary: This study compared the influence of water, oil, and friction modifier (FM) on wheel-rail adhesion and damage in the curve section. FM samples with different solid particles were tested for their tribological performance along with water and oil. The results showed that the shear strength of the third body material and the hardness of solid particles in FM greatly affected friction control performance, with a change in particle hardness leading to either lack of lubrication or over lubrication, both detrimental to the wheel and rail interface. The most suitable particle in this study was kaolin.
Article
Engineering, Mechanical
Bing Wu, Guangwen Xiao, Boyang An, Tao Wu, Quan Shen
Summary: This study aims to reproduce the dynamic wheel-rail interaction behavior under various interfacial contaminations through experimental and numerical modeling methods, in order to simulate wheel-rail rolling contact damage. The study found that under high-speed and wet conditions, the wheelsets slide and experience severe wear in the low adhesion zone.
ENGINEERING FAILURE ANALYSIS
(2022)
Article
Engineering, Mechanical
Kang-jie Rong, Ye-long Xiao, Ming-xue Shen, Huo-ping Zhao, Wen-Jian Wang, Guang-yao Xiong
Summary: The study found that ambient humidity has a significant impact on the adhesion behavior between the wheel and rail interface. Low humidity levels mainly lead to fatigue wear, while high humidity levels result in abrasive wear. Increasing humidity can help rollers avoid excessive wear.
Article
Chemistry, Multidisciplinary
Chao Chen, Chun Tian, Jiajun Zhou, Gengwei Zhai, Hao Yu
Summary: In order to further research adhesion recovery, a new test-rig for wheel-rail contact experiments under large slip conditions was developed. The wheel-on-ring category of test-rig was used to preserve surface conditions on rail. The test-rig consisted of wheel assemblies, ring track, gearbox, motors and sprinkler system, designed for motor decoupling and precise slip control. Experimental observations showed the potential of the new test-rig for exploring adhesion recovery under various surface conditions.
APPLIED SCIENCES-BASEL
(2023)
Article
Engineering, Mechanical
Xin Zhao, Shuangchao Huang, Shan Yin, Jizhong Yang, Zhen Yang, Gongquan Tao, Zefeng Wen
Summary: A time-domain finite element model was developed to investigate the transient rolling contact of a driving wheelset over a curved track with Low Adhesion Zones (LAZs) shorter than 1.0 m. Structural vibrations of the wheelset were analyzed to explain the transient contact forces, creepages, and resulting irregular wear. LAZs on the high rails were found to be more detrimental than those on the low rails. The results shed light on the occurrence of flats and rolling contact fatigue in adverse weather conditions, even without significant wheel idling.
Article
Chemistry, Physical
Yunlei Zhang, Shuanhong Ma, Bin Li, Bo Yu, Haeshin Lee, Meirong Cai, Stanislav N. Gorb, Feng Zhou, Weimin Liu
Summary: The study developed a novel multilayered self-peeling switchable dry/wet adhesive with thermal-responsive curving behavior and switchable adhesion properties, and explained the dynamic curvature-induced switchable peeling mechanism theoretically. By integrating nanoparticles, remote control over switchable adhesion can be achieved. This research provides a new route for developing intelligent adhesion systems and mobile devices/robots.
CHEMISTRY OF MATERIALS
(2021)
Article
Engineering, Mechanical
Tobias D. Carrigan, James P. Talbot
Summary: Railways need frequent inspection to maintain acceptable levels of rail roughness. This paper proposes a cost-effective method for near-continuous roughness monitoring using accelerometers mounted on in-service railway vehicles. The method addresses the variation in track support stiffness and wheel-to-wheel vibration coupling, and also considers the effect of wheel roughness on axle-box acceleration. The developments are evaluated through numerical simulation and measurement trials.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2023)
Article
Materials Science, Coatings & Films
Chua Ling Ling, Muhammad Azizi Mat Yajid, Mohd Nasir Tamin, Maslinda Kamarudin, Mustapha Ali Azhar Taib, Norlin Nosbi, Wan Fahmin Faiz Wan Ali
Summary: This study aims to improve the performance of cutting tools by applying AlCrN coating on the WC-Co substrate. The results showed that the roughened substrate and various deposition temperatures significantly influenced the coating phase formation, hardness, and wear performance.
SURFACE & COATINGS TECHNOLOGY
(2022)
Article
Engineering, Mechanical
Ji-hua Liu, Pi-jie Yu, Yu-jun Zhou, Zhi-biao Xu, Yong-jian Li, Peng Li, Zheng Zhao, Cheng-gang He, Ming-xue Shen
Summary: The effects of different shapes of lasered microtextures on the friction properties, wear and fatigue damage of wheel/rail materials were studied. The results showed that rectangular and rhombic textures have better lubricating effects, and the textured rail and coupled wheel steels exhibit better rolling contact fatigue resistance.
Article
Engineering, Mechanical
Yankui Song, Ke Xiao, Guo Xiang
Summary: The novelty of this study lies in constructing an Entropy-based wear and fluid-solid-thermal (FST) coupled model for journal bearings, and revealing the transient interaction behavior between wear evolution and FST evolution during repeated starting and stopping. The wear rate is measured experimentally, and the contact temperature, friction coefficient and normal contact force are obtained from the validated FST model. Wear tests and numerical calculations are conducted to validate the predicted wear rate and investigate the time-varying wear and FST evolution of journal bearings.
Article
Engineering, Mechanical
Xin-long Liu, Xin Guan, Yuan Zhong, Qian Xiao, Yong Cao, Wu-lue Zhang, Song Zhang, Yi-ting Zheng, Ming-sheng Gao, Dao-yun Chen, Wen-bin Yang
Summary: Gaps in the conductor rail joints of intercity trains have an impact on current transmission and the wear of carbon skateboards. These gaps decrease the coefficient of friction, increase electrical contact resistance, and affect the wear rate of carbon skateboards.
Article
Engineering, Mechanical
Yuhang Wu, Conglin Dong, Xiuqin Bai, Chengqing Yuan
Summary: The study developed a new composite material by incorporating hexagonal boron nitride (h-BN) particles into a thermoplastic polyurethane (TPU) matrix, which exhibited excellent self-lubricating properties and reduced frictional excitation forces. The addition of h-BN particles effectively reduced the coefficient of friction, decreased fluctuation amplitude, enhanced wear resistance, and attenuated vibration behaviors.
Article
Engineering, Mechanical
Tiancheng Ouyang, Xiuyang Sun, Wentao Tang, Yinxuan Li, Zhi Qun Tian, Yanzhou Li
Summary: By adding nitrogen-doped graphene and C60 nanoparticles to the lubricant, a highly efficient nano-lubricant with vibration and noise reduction properties is synthesized.
Article
Engineering, Mechanical
Xin Zhuo, Jun Cao, Haibo Huang, Li Liu, Xinkun Suo, Peiqing Ye, Zeshan Abbas
Summary: A polymer coating prepared by liquid spraying technology on the surface of 20CrMo steel demonstrates good tribological and anti-cavitation erosive properties. It can effectively replace CuPb24Sn copper alloy in valve plates for pumps under different lubrication conditions. The coating exhibits adhesive wear and reduces frictional loss, and mainly shows abrasive wear under complex working conditions. Its lipophilicity, high hardness to elastic modulus ratio, and corrosion resistance are the main influencing factors for its performance.
Article
Engineering, Mechanical
Md. Aminul Islam, Jiaren (Jimmy) Jiang, Yongsong Xie
Summary: Erosion-corrosion is a major factor in material loss and reduced useful life of hydro-transport equipment. This study evaluates the erosion-corrosion characteristics of different materials and finds that matrix wear affects the degradation of carbides. Sufficient wear and corrosion resistance in the surrounding matrix are important for good erosion-corrosion resistance.
Article
Engineering, Mechanical
Andre Dubois, Oussama Filali, Laurent Dubar
Summary: This study investigates the effect of surface roughness, contact pressure, and lubrication on the onset of galling in aluminum 6082-T6 using a pin-on-plate tribometer. The experimental results show that the roughness and lubricants play a significant role in preventing galling.
Article
Engineering, Mechanical
Jizhan Wu, Peitang Wei, Guoqiang Liu, Difa Chen, Xiuhua Zhang, Taimin Chen, Huaiju Liu
Summary: This study conducted a comprehensive evaluation of the DLC coating treatment on the loading capacity of gears and characterized the surface features and fatigue performance. The results demonstrate that DLC coating significantly improves the hardness and surface residual compressive stress of the gears, as well as enhances their contact fatigue performance.
Article
Engineering, Mechanical
Yangping Liu, Hwaran Lee, Annsley Mace, Jeremy L. Gilbert
Summary: An AFM-based single asperity tribology method was used to investigate the wear performance of carbides and base metal matrix in high carbon CoCrMo alloy. The wear behavior of the two types of carbides was stress-dependent and influenced by chemical composition. Cr-rich carbides exhibited higher wear resistance compared to Mo-rich carbides.
Article
Engineering, Mechanical
Zdenek Riha, Michal Zelenak, Akash Nag, Jakub Poloprudsky, Tomas Kruml, Sergej Hloch
Summary: This study investigates the erosion performances of a high-speed modulated jet (MWJ) and continuous water jet (CWJ). By comparing different nozzles and water jet powers, the effects of modulated and continuous jets on aluminum alloy were studied. The results show that under certain conditions, modulated jet can create deeper and sharper grooves while reducing the impact of lateral flow.
Article
Engineering, Mechanical
Chunyu Yu, Weipu Li, Yang Guo, Xianbin Sun, Fanli Hong, Ning Sun, Qinghai Zhang
Summary: This study explores the relationship between the wear rate of train brake pads and its features, and proposes a method for predicting the wear rate suitable for small sample data. Grey relational analysis and Pearson correlation analysis are used to determine the preferred features that affect the wear rate, and a BOA-BP model is established for prediction. The results show that BOA-BP exhibits better advantages in prediction with small samples.
Article
Engineering, Mechanical
Shan Yin, Xin Zhao, Shuangchao Huang, Zefeng Wen, Xuesong Jin
Summary: This study simulated the rolling contact of a driving wheelset over tangent and curved tracks at a speed up to 500 km/h using an explicit finite element approach to derive creep curves. The comparison between quasi-steady curves and transient curves in the presence of rail corrugation helped to identify cases where traditional theories are inapplicable and where transient effects must be considered. Additionally, the study further analyzed the influence of middle/high-frequency vibrations in the presence of rail corrugation.
Article
Engineering, Mechanical
Jiyao Zhang, Yuanlie Yu, Junlei Tang, Yingying Wang, Honggang Sun, Kaikai Song, Jianhong Gong, Pingping Liu, Xiaoming Liu, Lina Hu, Parthiban Ramasamy, Juergen Eckert
Summary: The influence of high-carbon addition on the microstructure, hardness, and wear behavior of CoCrNi alloy was investigated. It was found that the addition of carbon resulted in the formation of carbide particles, enhancing the hardness and improving the wear resistance. Fracture and detachment of hard carbides during friction introduced additional abrasive particles, transitioning the wear mechanism from adhesive-dominated to abrasive-dominated.
Article
Engineering, Mechanical
Yanfei Liu, Shengtao Yu, Ruize Zhang, Xiangyu Ge, Wenzhong Wang
Summary: This study reports the tribological behavior of nanodiamond plate (NDPL) as a nanoadditive for the first time and compares it with nanodiamond particles (NDPA). The results show that NDPL provides better lubrication performance at higher concentrations, and the sliding between NDPLs and the structural transformation from sp3 to sp2 carbon play a crucial role in lubrication and wear resistance.