Tribology Letters最新文献

{"title":"Regime-Dependent Effects of Multiscale Geometry on Stainless Steel–Ice Friction","authors":"Ernests Jansons,&nbsp;Igor Velkavrh,&nbsp;Teemu Lemmettylä,&nbsp;Martins Rubenis,&nbsp;Renars Vitols,&nbsp;Miks Sereiko,&nbsp;Viesturs Lacis,&nbsp;Janis Lungevics","doi":"10.1007/s11249-026-02183-4","DOIUrl":"10.1007/s11249-026-02183-4","url":null,"abstract":"<div><p>Friction between solids and ice is a complex, multiscale phenomenon influenced by factors such as surface geometry, mechanical parameters, and ambient conditions. However, the combined effects of macro-, micro-, and nano-scale geometry on ice friction remain insufficiently quantified. This study systematically investigates the impact of surface curvature and roughness on the coefficient of friction between stainless steel and ice. Controlled modifications were introduced to cross-section radius (7–16 mm), longitudinal radius (3–8 m), and surface roughness (Sa 0.02–0.17 µm), spanning geometry scales from metres to nanometres. Friction tests were conducted using a 13.7 m long tribometer at two ambient conditions: “cold” (− 10 °C ice, − 3 °C air, 80% RH) and “warm” (− 2 °C ice, 2 °C air, 83% RH), at two applied loads (300, 600 N) and sliding velocities (2, 4 m/s). A multiscale surface characterisation framework was developed to correlate 3D surface geometry with friction results. Results indicate that macro-geometry primarily affects ice friction. By reducing the cross-section radius, the coefficient of friction decreased by up to 35% in cold conditions but increased by 20% in warm conditions, suggesting behaviour consistent with a transition between boundary and hydrodynamic friction regimes. Surface texture modifications (simultaneously affecting amplitude, directionality, and skewness) showed a lower, load-dependent effect (up to 15%), with interpretation complicated by co-variation of multiple texture parameters. The results show that identical geometry modifications can lead to opposite friction trends depending on ambient thermal conditions, consistent with regime-dependent friction behaviour.</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":"74 3","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11249-026-02183-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148614794","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":"Tribological Performance of MoS2-Coated 6082-T6 Aluminium: Influence of Laser Texture Density and Pin-on-Disc Test Configuration","authors":"Juan Ignacio Ahuir-Torres,&nbsp;Tahsin Tecelli Öpöz,&nbsp;Guangyu Zhu,&nbsp;Musa B. Bashir,&nbsp;Hiren R. Kotadia","doi":"10.1007/s11249-026-02186-1","DOIUrl":"10.1007/s11249-026-02186-1","url":null,"abstract":"<div><p>The 6082-T6 aluminium alloy is widely used in engineering applications but its broader deployment is restricted by poor wear and friction resistance. Solid lubricants such as molybdenum disulphide (MoS₂) can improve its tribological performance; however, their effectiveness is limited by short service life and the need for frequent replenishment. Laser surface texturing (LST) has proven effective in extending lubricant lifespan, yet the influence of tribological system configuration on textured, solid-lubricated aluminium surfaces remains insufficiently understood. In this study, the combined effects of groove texture density (TD) and pin-on-disc configuration on the tribological behaviour of MoS₂-coated 6082-T6 aluminium alloy were systematically investigated. Groove patterns with TD values ranging from 25 to 100% were fabricated using an infrared nanosecond pulsed fibre laser, and MoS₂ coatings were applied by spraying. Tribological performance was evaluated under dry and lubricated conditions using three configurations: textured pin, textured disc, and both pin and disc textured. Finite element analysis was conducted to examine the influence of surface texturing and groove orientation on compression and ejection normal stresses. Laser surface texturing extended the MoS₂ lubricant service life by approximately 2 to 50 times compared with non-textured surfaces, depending on TD and configuration. Increasing TD consistently enhanced lubricant lifespan. Among all configurations, the pin-and-disc system exhibited the longest service life, while the textured pin configuration showed the shortest. Finite element results identified ejection stress as the dominant factor governing lubricant depletion, providing new insight into stress-mediated solid lubrication mechanisms for 6082-T6 aluminium alloy.</p></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"74 3","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11249-026-02186-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148614793","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":"Molecular Configuration-Dependent Interfacial Anchoring: Enhancing Current-Carrying Tribology of Graphene/Nitrogen-Heterocyclic Polymer Nanocomposites","authors":"Qingsong Jing,&nbsp;Xueling Wang,&nbsp;Xu Tang,&nbsp;Dancong Zhang,&nbsp;De Lv,&nbsp;Hongrui Zhang,&nbsp;Jianxin Wang,&nbsp;Ming Zhou","doi":"10.1007/s11249-026-02157-6","DOIUrl":"10.1007/s11249-026-02157-6","url":null,"abstract":"<div><p>Interfacial failure under electro-mechanical coupling critically limits the reliability of conductive greases. To overcome graphene restacking and reduce the chemical damage risk associated with ionic liquid-modified systems, polypyrrole/graphene (G/PPy) and polybenzimidazole/graphene (G/PBI) nanocomposites were synthesized via in situ polymerization and evaluated under current-carrying sliding conditions. Compared with the PAO40 base grease, G/PPy showed the largest relative reduction in electrical contact resistance (ECR). Its stable ECR decreased by 57.4%. Among the tested systems, G/PBI exhibited the lowest average coefficient of friction, with the value reduced to 0.0972. Its specific wear rate decreased by 38.2% relative to the base grease. The non-seizure load of G/PBI reached 1050 N. Raman and XPS analyses indicate that the improved behavior of G/PBI is associated with the formation of a more stable composite tribofilm containing retained carbonaceous species and nitrogen-containing interfacial species. In particular, the higher relative Fe–N contribution in the G/PBI-lubricated wear track is consistent with more favorable nitrogen-related interfacial coordination, rather than serving as standalone proof of a unique anchoring pathway. These results suggest that regulating the molecular configuration of nitrogen-containing graphene nanocomposites can improve current-carrying lubrication by balancing friction reduction, wear resistance, electrical contact preservation, and interfacial chemical stability.</p></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"74 3","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148614596","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":"Electrical Contact Resistance of Rough Surfaces in the Elastoplastic Regime","authors":"X. M. Liang,&nbsp;G. F. Wang,&nbsp;M. Ciavarella","doi":"10.1007/s11249-026-02181-6","DOIUrl":"10.1007/s11249-026-02181-6","url":null,"abstract":"<div><p>We investigate the electrical contact resistance of elastoplastic Gaussian rough surfaces by combining a boundary element contact model with a pressure-cap approximation for plasticity and a separate resistance calculation based on the resulting contact maps. In the purely elastic limit, the numerical results recover Barber’s relation between electrical contact resistance and incremental normal stiffness. When plastic deformation becomes significant, this elastic relation no longer holds: for a given normal load or stiffness, elastoplastic contacts exhibit lower resistance because plastic flattening modifies the real contact area and the morphology of conducting spots. We further show that the resistance–load curves can be collapsed onto a master curve by introducing a dimensionless load-scaling factor. This factor depends systematically on the plastic flow pressure normalized by the product of the plane-strain elastic modulus and the root-mean-square slope of the rough surface, providing a simple empirical description of the transition from the plastic limit to the elastic limit.</p></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"74 3","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148614606","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":"From Data Islands to Knowledge Networks in Tribology: Understanding the Modern Data Architecture","authors":"Nick Garabedian,&nbsp;Wilfred T. Tysoe","doi":"10.1007/s11249-026-02179-0","DOIUrl":"10.1007/s11249-026-02179-0","url":null,"abstract":"<div><p>The scientific research community stands at a critical juncture in its approach to data management. While we have successfully transitioned from manual to computer-controlled experiments across diverse fields (from tribology to materials science, from chemistry to bioengineering), our data practices have not kept pace with the exponential growth in data generation and the emergence of artificial intelligence. This paper explores why investing time in understanding modern data architectures is essential, not just as another publication requirement, but also as the foundation for accelerated collaborative discovery within our organizations and across the community. We examine the current landscape through recent survey data, explain the fundamental concepts behind FAIR (<u>F</u>indable, <u>A</u>ccessible, <u>I</u>nteroperable, and <u>R</u>eusable) data principles with the technical depth needed to assess true FAIR-ness, and present FAIR digital twins of scientific work as one concrete implementation that can transform isolated data into interconnected knowledge networks. Just as computer-controlled instruments revolutionized our experimental capabilities, modern data architectures promise to be the next enabling technology that amplifies our collective scientific output. While we use tribology as our primary field of interest, the principles apply equally to any experimental science dealing with multi-dimensional, context-dependent data.</p></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"74 3","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148614465","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":"Synergy Between MoS2 and Graphite in Vacuum-Impregnated Sintered Steels: Impact on Tribolayer Stability and Wear Mechanism Transitions","authors":"C. Madrid,&nbsp;P. Martin,&nbsp;N. Araya,&nbsp;A. N. Klein,&nbsp;R. Henriquez,&nbsp;C. Aguilar","doi":"10.1007/s11249-026-02180-7","DOIUrl":"10.1007/s11249-026-02180-7","url":null,"abstract":"<div><p>Frictional losses account for nearly a quarter of global energy consumption, underscoring the urgent need for advanced self-lubricating materials that enhance energy efficiency throughout their entire life cycle, from manufacturing to end use. Solid lubricant films are limited by wear, whereas vacuum impregnation of sintered components provides sustained lubrication and tunable tribological properties. Here, a novel strategy for engineering low-alloy sintered steels with superior dry sliding performance via vacuum impregnation with MoS₂ and graphite is reported. While each lubricant is widely used, its combined impregnation into porous steels has not been previously explored. Tribological testing revealed a synergistic effect: samples impregnated with both lubricants achieved an exceptionally low coefficient of friction (0.056 ± 0.0052) under dry sliding conditions and wear rates on the order of 10⁻⁶ mm³/N m, outperforming single-lubricant systems. Microstructural and Raman spectroscopy analyses demonstrated that the lamellar overlap of MoS₂ and graphite suppresses the formation of abrasive debris and MoO₃ oxidation, shifting the wear mechanisms from mild oxidative and abrasive wear toward stable plastic flow. Regarding the behavior of the solid lubricants, MoS₂ retained its bulk-like lubricity, while graphite experienced limited degradation (&lt; 20%) with a partial shift from sp² to sp³ hybridization, enabling a durable, self-replenishing tribolayer. These results validate the sintering and impregnation route as a low-cost, highly effective way to improve tribological properties of mechanical components by taking advantage of the already existing pores on sintered materials.</p></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"74 3","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148613796","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":"High-Pressure Rheology of Squalane:Shear Dependence","authors":"Scott Bair","doi":"10.1007/s11249-026-02178-1","DOIUrl":"10.1007/s11249-026-02178-1","url":null,"abstract":"<div><p>The field of elastohydrodynamic lubrication (EHL) has gleaned little benefit from one-hundred years of high-pressure viscometers. Tribologists have sought substitutes for difficult viscometry [1], and a recent substitute is non-equilibrium molecular dynamics (NEMD) simulation. Attempts to predict film thickness and friction with the Eyring sinh-law for shear dependence have used alterations of the temperature and pressure dependences [1]. Unfortunately, the same errors are being made with NEMD. The shear stress capability of pressurized thin-film Couette viscometers has been significantly expanded. Film thickness and friction can be predicted from viscometry [1], and NEMD simulations do not provide the same constitutive behavior as viscometers except for very low-viscosity cases.</p></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"74 3","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11249-026-02178-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466222","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":"Dataset on Surface Topographies Prepared by Micro-Milling and Their Friction Coefficients in Dry Sliding","authors":"Burçak Avcı,&nbsp;Pooria Farahani,&nbsp;Oltmann Riemer,&nbsp;Bernhard Karpuschewski,&nbsp;Andreas Mehner","doi":"10.1007/s11249-026-02177-2","DOIUrl":"10.1007/s11249-026-02177-2","url":null,"abstract":"<div><p>These data were collected to systematically characterize the relationship between 3D surface topography and dry sliding friction behavior for 32 distinct micro-milled textures on hardened X153CrMoV12 tool steel. The dataset was designed to provide a comprehensive experimental basis for understanding running-in behavior and orientation-dependent friction. It is intended to support the development of advanced numerical simulations in lubricant-free forming applications. The dataset includes 96 high-resolution confocal laser scanning microscopy images that are presented along with their milling parameters and selected ISO 25178 areal roughness parameters. These are linked to tribological data from unidirectional linear scratch tests (1 N load, 50 cycles) conducted at perpendicular sliding orientations. The records contain raw friction logs, a processed steady-state friction table, a representative validation plot, and the Python code used for data extraction. All files, including a detailed methodology document, are openly available on the Zenodo repository. By providing an entire characterization parameter sequence (from milling to friction results), this dataset provides a comprehensive view.</p></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"74 3","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466390","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":"Shear-Activated Fibrillation Enables Structural Adhesion in PTFE","authors":"Abdulmalik Yusuf,&nbsp;Ben Gould,&nbsp;David L. Burris","doi":"10.1007/s11249-026-02156-7","DOIUrl":"10.1007/s11249-026-02156-7","url":null,"abstract":"<div><p>Adhesion of low surface energy polymers is typically limited by work of adhesion and elastic fracture mechanics. Here, we demonstrate that unsintered polytetrafluoroethylene (PTFE) fine powder exhibits debonding energies orders of magnitude higher than its sintered counterpart due to shear-activated fibrillation and progressive load redistribution. Using a custom microtribometer, we measured adhesion force and debonding energy of individual PTFE particles in contact with polished stainless steel under controlled normal load with varying shear cycles. While sintered PTFE displayed minimal adhesion (≈5 mJ/m²), unsintered PTFE exhibited 237 mJ/m² without shear, increasing to over 4000 mJ/m² after 1000 shear cycles. <i>In-situ</i> tensile measurements and quasi in situ SEM imaging revealed fibril bundles spanning millimeter-scale separations following pull-off. Incremental extension testing demonstrated sustained tensile load during progressive separation, consistent with fibrillar drawing and crystalline unzipping rather than elastic fracture. Molecular weight and polymer modification modulated peak force and energy dissipation but preserved the shear-activated mechanism. The measured debonding energies exceed the work of adhesion by more than two orders of magnitude, demonstrating that structural load sharing and progressive fibril failure dominate interfacial separation. These findings indicate that adhesion of PTFE in shear-processed systems, including transfer films and related architectures such as dry electrodes, may be influenced and, under appropriate conditions, dominated by mechanically activated fibrillation.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div><p>`</p></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"74 3","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11249-026-02156-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148465629","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":"Finite Element Study of Asperity Interactions with Adhesion as Body Force","authors":"Uzair Iqbal,&nbsp;M. S. Bobji","doi":"10.1007/s11249-026-02169-2","DOIUrl":"10.1007/s11249-026-02169-2","url":null,"abstract":"<div><p>The adhesive contact between bodies is a fundamental problem and is known to play a significant role in tribology, nanotechnology, colloidal science and many industrial processes. Adhesion arising from van der Waals (vdW) interactions strongly influences the mechanical behaviour of the interacting bodies. In this work, we study adhesive contact between an elastic hemispherical asperity and a rigid half-space using a self-consistent body-force (SCBF) formulation that incorporates vdW adhesion and steric repulsion as body forces. The body force formulation overcomes the restrictive assumptions of surface-force methods. A two-step quasi-static procedure (Appendix A) avoids the numerical ill-conditioning near jump-to and jump-off contact instabilities, enabling analysis of compliant systems. This study elucidates the effects of material and geometric parameters on adhesive contact behaviour. Results demonstrate that material compliance and geometry systematically influence elastic deformation, pull-off force, and instability separation. For stiff bodies (<span>(mu &lt; 0.1)</span>), geometric size has a significant impact on the pull-off. For the range <span>(0.1&lt; mu &lt; 1)</span>, it is found that the pull-off force strongly depends on both the elastic modulus and the asperity size. However, for highly compliant bodies (<span>(mu &gt; 1.5)</span>), the pull-off force is weakly dependent on both the properties and may plateau before reaching the JKR value. The results also show that for all values of <span>(mu)</span>, the instability is primarily controlled by elastic modulus, and that the asperity size only becomes a determining factor for <span>(mu &gt; 4)</span>. We further establish two geometry-based contact definitions: <span>(a_0)</span> and <span>(a_{text {max}})</span>, which qualitatively match the DMT-M and JKR theory descriptions, respectively and highlight the limitations of the classical models. The SCBF formulation eliminates the stress and displacement singularities of classical analytical models. The volumetric distribution of attractive force reveals a “sandwiching” effect, resulting in significantly high compressive stress magnitudes at the contact centre. The high subsurface stresses suggest that realistic adhesive contacts can potentially lead to material failure, accompanied by substantially increased energy dissipation, which fundamentally challenges purely elastic models. This framework advances our fundamental understanding of “soft adhesive contact” mechanics and adhesive wear mechanisms, enabling the predictive design of surfaces with controlled adhesion by better representing contact behaviour across a range of materials, from stiff to highly compliant.</p></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":"74 3","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148465277","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}