Tribology Letters最新文献

{"title":"Investigation on Acoustic Emission Characteristics of Lubricating Grease in Hydrodynamic Lubrication Regime","authors":"Xuanrui Zhang,&nbsp;Dong Zhen,&nbsp;Guojin Feng,&nbsp;Zewen Zhou,&nbsp;Xiaoxia Liang,&nbsp;Hao Zhang,&nbsp;Fengshou Gu","doi":"10.1007/s11249-025-01995-0","DOIUrl":"10.1007/s11249-025-01995-0","url":null,"abstract":"<div><p>Traditional methods for monitoring lubrication and wear typically rely on indirect indicators such as temperature changes, vibration, or lubricant contamination. However, these approaches have limitations in that they are unable to provide real-time, direct insights into the micro-scale interactions occurring between frictional interfaces. This paper aims to explore the mechanisms and characteristics of acoustic emission (AE) signals generated by lubricants, particularly greases, in hydrodynamic lubrication (HL) regime, thereby enabling early detection of surface wear and degradation in mechanical systems. Based on the fundamental theory of elastic deformation strain energy release from micro-asperities, a model for AE signals of lubricants in HL regime was established. Experimental studies using a rheometer platform were conducted on lubricants to compare their flow properties and related friction signals. The results indicate that both lubricating greases and oils share similar characteristics, where shear rate and lubricant viscosity are significant factors affecting AE signals. These findings provide essential references for monitoring the lubrication state of friction pairs and the health condition of lubricants, especially in detecting early surface wear.</p></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"73 2","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143826564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A New MRCAHE Method for Wear Particle Image Enhancement Based on Improved Online Optical Microfluidic Sensor","authors":"Zhenzhen Liu,&nbsp;Jingrui Wang,&nbsp;Yan Liu,&nbsp;Hongfu Zuo,&nbsp;Xin Li,&nbsp;Jiale Miao,&nbsp;Xiaolei Hu","doi":"10.1007/s11249-025-01994-1","DOIUrl":"10.1007/s11249-025-01994-1","url":null,"abstract":"<div><p>As direct byproducts of frictional interactions between contacting surfaces, oil wear particles exhibit varied physical properties that provide essential insights into the underlying wear mechanisms and degree of wear severity. Current online optical microfluidic monitoring sensors demonstrate inadequate imaging quality, especially in ferrograph sensors, where particles frequently form chains, hindering real-time monitoring. To address this challenge, an integrated optimization approach has been developed, emphasizing two key aspects: the structural redesign of the online optical sensor and the enhancement of wear particles imaging. We develop a high-precision optical monitoring sensor, which facilitates both conventional particle counting and size detection, as well as the extraction of high-definition texture images of particles in real time. Initially, as the scattering accounts for the majority of the total light energy attenuated, we compute the light intensity scattered by particles in oil. The influence of particle size, scattering angle, particle type, and incident light wavelength on scattering intensity is analyzed, establishing the basis for improving the image quality of wear particles. Then, to alleviate the substantial image degradation induced by oil, characterized by diminished contrast, color attenuation, blurring, and indistinct features, we propose a hybrid image enhancement method MRCAHE, which integrates Multi-scale Retinex with Color Restoration (MSRCR) and Contrast-Limited Adaptive Histogram Equalization (CLAHE). The sensor’s performance is ultimately validated on a high-speed, heavy-load gear fault simulation test bench. Experimental results demonstrate that the sensor consistently collects distinct images of wear particles, and the MRCAHE enhancement method significantly improves deblurring, texture extraction, color restoration, and sharpness. This portable oil wear particle monitoring sensor provides a robust technical foundation for condition monitoring, fault diagnosis, and intelligent maintenance of rotating machinery.</p></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"73 2","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143824590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Finite Element Simulation Method for Fretting Wear Considering Double-Side Wear Behavior","authors":"Yifan Song,&nbsp;Pei Yan,&nbsp;Wenxiang Zhao,&nbsp;Tingwei Sha,&nbsp;Zhicheng Dai,&nbsp;Siyu Li,&nbsp;Huiqing Gu,&nbsp;Xibin Wang","doi":"10.1007/s11249-025-01992-3","DOIUrl":"10.1007/s11249-025-01992-3","url":null,"abstract":"<div><p>Fretting-wear-induced failure of contacting surfaces threatens the safety of assemblies, which means the wear behavior on both contacting surfaces should be fully considered. In this paper, a finite element simulation method was proposed to reveal fretting wear behavior, which simultaneously considered double-side wear of both contacting surfaces. The user subroutine UMESHMOTION based on Archard’s equation was used to describe the fretting wear behavior. The finite element model was tested and validated using results obtained from cylinder-on-flat tangential fretting wear tests conducted under varying fretting amplitudes. The topography and cross-sectional profile characteristics of fretting scar were compared. The dynamic wear behaviors and fretting regime were analyzed from the tangential force–displacement curves and the ratio of shear stress to contact pressure. Besides, the variation of wear volume with fretting cycles was also analyzed. The results obtained from model considering double-side wear shown a better agreement with the experimental results compared to those from model considering single-side wear.</p></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"73 2","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143821923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bidirectional Object Transport on Biomimetic Setal Array with Friction Anisotropy","authors":"Zhuyu Zhou,&nbsp;Tianyuan Liu,&nbsp;Xiyin Gu,&nbsp;Zhongmeng Zhu,&nbsp;Qian Cheng,&nbsp;Han Jiang","doi":"10.1007/s11249-025-01993-2","DOIUrl":"10.1007/s11249-025-01993-2","url":null,"abstract":"<div><p>The friction anisotropy arising from the unique deformation mechanism of insect setae holds significant potential for object transport applications. This study presents a biomimetic setal array, which is capable of achieving controllable bidirectional transport of objects under vibration excitation. Experimental results reveal a complex phenomenon: as the vibration frequency increases, the transport velocity of the object initially increases, subsequently decreases and reverses direction, and ultimately undergoes another reversal of transporting direction at a significantly higher velocity. The effect of friction anisotropy on this phenomenon is thoroughly investigated through analysis of the transport process and the friction behavior of insect setae in nature. Additionally, an analytical model is developed, revealing the underlying mechanism of transport and providing a guidance for transport regulation. Following a detailed discussion on the effect of object mass on this novel transport strategy, this biomimetic setal array is demonstrated to enable controllable sorting and intelligent transport of objects.</p><h3>Graphical Abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"73 2","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143818108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Some Remarks on a Recent Wear Theory","authors":"M. Ciavarella","doi":"10.1007/s11249-025-01984-3","DOIUrl":"10.1007/s11249-025-01984-3","url":null,"abstract":"<div><p>Persson et al. in (Rubber wear: experiment and theory. arXiv:2411.07332, 2024) and Xu and Persson in (Sliding wear: role of plasticity. arXiv: abs/2412.13129, 2024) have recently proposed an interesting theory of wear which is based on particle formation due to fatigue crack growth at different scales of roughness. The theory perhaps is the first one to take into account of a full characterization of the roughness, and obtains semi-quantitative prediction of wear coefficients for rubber and PMMA, but in the original form, many details of actual roughness features and the material properties do not permit to elucidate general simple trends. We attempt to make general comments to show the main effects of the various macroscopic parameters in the theory, with qualitative comparisons having in mind the case of metals wear for which we found experimental trends, at least for the dependence on friction coefficient. It is found that wear rate in the elastic theory very strongly depends on friction coefficient and on rms roughness, showing even a regime of wearless behaviour below friction coefficient of about 0.2—which may indicate transition to other mechanisms, like adhesive wear. It is shown that an elasto-plastic theory probably mitigates these effects, as a fully plastic one depends only quadratically on friction coefficient, and has no dependence at all on any feature of roughness. However, the present oversimplistic perfectly plastic model truncating the elastic prediction, and the use of a crack propagation theory which is irrespective of large plastic flow can make the theory more hardly quantitative in general. In addition, hardness at asperity scale may increase due to size effect, so the elastic model may be the most appropriate choice in many cases. Along with many other complex effects known in wear (even limiting attention to fatigue wear), it remains, therefore, to be investigated how generally the Persson theory can result in quantitative predictions.</p></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"73 2","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11249-025-01984-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143778148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dislocation Slip and Damage Evolution Behavior in the Dent-Induced Pitting Process of M50 Bearing Steel","authors":"Wanjia Li,&nbsp;Xiangxu Meng,&nbsp;Yanwei Zheng,&nbsp;Jinbao Huang,&nbsp;Tingjian Wang,&nbsp;Le Gu,&nbsp;Liqin Wang,&nbsp;Chuanwei Zhang","doi":"10.1007/s11249-025-01985-2","DOIUrl":"10.1007/s11249-025-01985-2","url":null,"abstract":"<div><p>Pitting is a typical failure behavior in rolling contact fatigue. Generally, there are two different pitting cases. One is the corrosion-induced pitting, and the other is the dent-induced pitting. This study focused on the dent-induced pitting. The surface dent is caused by the particle compression on the ring surface. During the compression process, grain distribution affects the dent geometry and the damage evolution behavior. However, researchers have almost ignored the effects of grain distribution on surface defect-induced RCF. Therefore, the authors proposed a crystal plasticity continuum damage method (CP-CDM) model by combining crystal plasticity constitutive equations with continuum damage equations to study the grain distribution effects on the damage evolution of the surface defect-induced RCF. The results show that the proposed model can simulate the crack propagation characteristics of the RCF. Grain distribution has effects on the damage propagation behavior randomly. However, the lead cracks have little difference for different grain distribution microstructures. The damage evolution behavior of pitting is affected by the interaction between stress concentration from the shoulder and the crack tip and strain localization from the grain boundaries. Moreover, the cracks in the surface pitting and the subsurface spalling evolve simultaneously.</p><h3>Graphical abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"73 2","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biphasic Lubrication Theory of Hydrogels: Transient Response and Sample Size Effects","authors":"Tetsuo Yamaguchi,&nbsp;Yoshinori Sawae","doi":"10.1007/s11249-025-01986-1","DOIUrl":"10.1007/s11249-025-01986-1","url":null,"abstract":"<div><p>Hydrogels are soft and wet materials with remarkable properties. Among such properties, low friction has attracted much attention from scientists and engineers. While many studies investigated the correlation between material properties and frictional behavior, little attention has been paid to other effects, such as sample sizes. In this study, we developed a theoretical model based on the biphasic lubrication theory to describe the frictional behavior of hydrogels against a glass substrate in the rotational shear test. Consequently, we obtained analytical solutions for the time evolutions of friction coefficient, hydrostatic pressure, and elastic stresses. To validate our model, we prepared cylindrical PVA (Polyvinyl alcohol) hydrogels with different radii and thicknesses and conducted friction experiments. We confirmed reasonable agreements with theoretical predictions for the transient responses and their size dependences. Interestingly, we found that the friction coefficient at the initial phase decreased drastically with decreasing thickness. Our results indicate the fundamental importance of bulk transport in surface friction of hydrogels, and the controllability of friction by varying the geometry of hydrogels.</p><h3>Graphical Abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"73 2","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11249-025-01986-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143735431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preliminary Investigation on the Critical Point for Wheel–Rail Adhesion Recovery Phenomenon Under Water-Based Conditions","authors":"Zhou Jiajun,&nbsp;Zhai Gengwei,&nbsp;Liu Yinhu,&nbsp;Xue Mingchen,&nbsp;Zhou Gaowei,&nbsp;Tian Chun,&nbsp;Wu Mengling","doi":"10.1007/s11249-025-01989-y","DOIUrl":"10.1007/s11249-025-01989-y","url":null,"abstract":"<div><p>Under lubrication conditions such as water and anti-wear fluids, the wheel–rail interface typically demonstrates a low-adhesion state. More and more evidence suggests that the adhesion coefficient is not static but dynamically coupled with the rolling and sliding behaviors of the wheels. When the slip ratio between the wheel and rail is high, strong friction can greatly improve the rail surface condition, resulting in adhesion recovery. Nevertheless, experimental research on wheel–rail adhesion under high-speed and high slip ratios is lacking, and especially the critical point of adhesion recovery has not been clarified. This study investigates the adhesion characteristics at a speed of 400 km/h and analyzes the relationship between changes in adhesion and wheel surface temperature under high slip ratio conditions. The results suggest that there is a strong correlation between the wheel surface temperature and the critical point for adhesion recovery. Lubricants such as water and anti-wear fluids have a critical lubrication failure temperature, and once this temperature is exceeded, the lubrication state will be damaged, leading to an adhesion recovery phenomenon.</p></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"73 2","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143726644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterisation of Friction Between Glass Tows: Comparison of Experiments and Finite Element Simulations Using an ALE Formulation","authors":"Hugo Jamet,&nbsp;Chayma Chahloul,&nbsp;Guillaume Helbert,&nbsp;Florent Bouillon,&nbsp;Nahiène Hamila","doi":"10.1007/s11249-025-01983-4","DOIUrl":"10.1007/s11249-025-01983-4","url":null,"abstract":"<div><p>The phenomenon of inter-yarn friction plays a crucial role in determining the behavior of woven materials. However, understanding and modeling this phenomenon remain complex due to the numerous parameters involved-such as normal force, velocity, angles, and sizing agents. To better analyze the influence of these various parameters on friction, a friction test bench without force sensors was developed, along with an associated finite element model. Motor control is used to vary carriage speed. An automatic image analysis method is used to measure the slippage between fiber tows. The model relies on an Arbitrary Lagrangian Eulerian (ALE) formulation, which provides simplified handling of inter-yarn contacts and slippage, while offering enhanced computational speed and robustness compared to a model based on a Lagrangian formulation. By comparing simulation results with experimental curves, a contact law was formulated, and its parameters were identified.</p><h3>Graphical Abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"73 2","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143726645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tribofilm Formation by Fe3O4 Nanoparticles as Lubricant Additives: Microscopic Insights into Growth Conditions and Mechanisms","authors":"Longji Guo,&nbsp;Yanan Yin,&nbsp;Lina Gao,&nbsp;Hao Lin,&nbsp;Yuzhen Liu,&nbsp;Kai Le,&nbsp;Xu Zhao,&nbsp;Xu Chen,&nbsp;Shusheng Xu","doi":"10.1007/s11249-025-01988-z","DOIUrl":"10.1007/s11249-025-01988-z","url":null,"abstract":"<div><p>Current research concerning Fe₃O₄ nanoparticles (NPs) as lubricant additives primarily focuses on the macroscale tribological performance, with insufficient exploration of anti-wear mechanisms at the microscopic scale. In this study, the formation and growth behavior of Fe₃O₄-based tribofilms was investigated. Oleic acid-modified Fe₃O₄ NPs dispersed in a polyalphaolefin base oil were tested between ZrO₂ balls and GCr15 steel substrates utilizing a reciprocating micro-tribometer. The morphology, microstructure, and chemical composition of tribofilms were meticulously characterized. Results revealed that the tribofilm primarily consisted of cubic Fe₃O₄ nanocrystals, consistent with initial particles. The organic modification layers of NPs were removed, facilitating direct inter-particle bonding. Growth mechanisms of tribofilms involving tribosintering of Fe₃O₄ NPs and shear-induced removal were proposed, demonstrating strong dependence on sliding cycles and contact pressure. Under an initial contact pressure of 1.15 GPa, the volume of the tribofilm increased with the number of sliding cycles, eventually reaching a state of saturation. While stress-dependent growth was observed, excessive stress led to wear on the substrate.</p><h3>Graphical Abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"73 2","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11249-025-01988-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143706947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}