Friction最新文献

{"title":"Wide-temperature-range tribological behavior and control mechanism of SnAg/ZrW\u0000 2\u0000 O\u0000 8\u0000 -incorporated Ni-based adaptive composite coatings","authors":"Xiyao Liu,Feng Qiao,Jun Wang,Lejia Qin,Bentian Luo,Jie Li,Zhiwei Lu,Li Chen,Jiliang Zhang","doi":"10.26599/frict.2026.9441300","DOIUrl":"https://doi.org/10.26599/frict.2026.9441300","url":null,"abstract":"Abstract To realize the adaptive regulation of friction performance for core mechanical components over a wide temperature range, an integrated antifriction and wear-resistant composite structure combining coating, texture, and lubricant was proposed and prepared. Arrayed circular micropore textures were fabricated on CSS-42 L high-temperature bearing steel with a nickel-based hard coating, and SnAg soft metal lubricant doped with the negative thermal expansion agent ZrW2O8 was filled into the textures. Cellular automaton models were established to simulate the diffusion process of the lubricant, and combined with systematic tribological experiments, the frictional behavior and adaptive regulatory mechanism at different temperatures were systematically analyzed. Simulation results based on cellular automata models show that with increasing temperature, the proportion of medium- and high-concentration regions of SnAg lubricant increases gradually and reaches 75.28% at 350 °C, confirming the favorable diffusion behavior at elevated temperatures. Tribological tests reveal that the 95Sn5Ag-filled coating and the 95Sn5Ag–10 wt% ZrW2O8-filled coating exhibit significantly superior tribological properties compared with the pure Ni-based coating across a wide temperature range. At 350 °C, the average friction coefficients of the 95Sn5Ag-filled coating and the 95Sn5Ag–10 wt% ZrW2O8-filled coating are 0.42 and 0.44, respectively, reduced by 35.4% and 39.7% compared with room temperature, and the wear rates decrease to 1.3×10−7 and 2.0×10−7 mm3·N−1·m−1. The lubricating layer thicknesses reach 4.48 and 4.18 μm, increasing by 164% and 80%, respectively. The 95Sn5Ag–10 wt% ZrW2O8-filled coating presents a more stable adaptive lubrication performance. The unique “inhibition at high temperatures and promotion at low temperatures” regulatory mechanism of ZrW2O8 effectively enhances the wide-temperature adaptability. The synergistic effect of coating, texture, and lubricant enables excellent antifriction and self-lubrication, which provides an efficient and feasible strategy for the active design and performance optimization of wear-resistant and lubricating functions of mechanical components.","PeriodicalId":12442,"journal":{"name":"Friction","volume":"41 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149021130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advances in nanofriction of ionic liquids confined at graphene-based materials","authors":"Muqiu Wu,Yi Xie,Ziyi Wang,Braham Prakash,Aatto Laaksonen,Xiaoyan Ji,Meirong Cai,Rong An","doi":"10.26599/frict.2026.9441277","DOIUrl":"https://doi.org/10.26599/frict.2026.9441277","url":null,"abstract":"Abstract Graphene and graphene-based materials are increasingly integrated into micro- and nanoelectromechanical systems, flexible electronics, and energy devices, wherein interfacial friction poses critical challenges. Ionic liquids (ILs), owing to their negligible volatility, high stability, and structural tunability, are promising lubricants for these systems. When confined on a graphene surface, ILs form layered films that are markedly distinct from their bulk structures and exhibit unique nanofrictional behaviors. This review establishes a mechanism-oriented substrate–IL–stimuli framework to connect interfacial descriptors (the surface properties of graphene, the molecular architecture of ILs, and external stimuli, i.e., humidity, temperature, and electric field) to interfacial ion structuring and nanofrictional outputs. Insights from atomic force microscopy (AFM), surface force apparatus (SFA), and molecular dynamics (MD) simulation studies are integrated to explain how the interfacial ion structure governs nanoscale friction. Transferable structure–property relationships are extracted from recent advances from AFM, SFA, and MD simulations to identify key challenges and propose a roadmap toward programmable graphene–IL lubrication for advanced nanodevices.","PeriodicalId":12442,"journal":{"name":"Friction","volume":"45 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149021131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wear protection by in-situ forming amorphous-nanocrystalline composite layer through friction-induced self-reaction","authors":"Jian Zhang,Meiqin Liu,Xuqi Shao,Haoran Zheng,Zhongyu Piao,Shuai Cui,Wenlong Zhou,Weitao Sun","doi":"10.26599/frict.2026.9441316","DOIUrl":"https://doi.org/10.26599/frict.2026.9441316","url":null,"abstract":"Abstract This study proposes a novel wear protection strategy that focuses on the in-situ construction of an amorphous-nanocrystalline composite layer via friction-induced mechanochemical reactions. To realize this concept, a multicomponent (FeSiB)xCuy (at.%) alloy was selected as the precursor material. Subsequently, sliding wear tests were conducted under distinct normal loads (10 N and 30 N) to control the input of mechanical energy. Under the higher load, an amorphous-nanocrystalline composite structure was formed, with nanocrystalline Cu embedded in an Fe-Si-B-O amorphous matrix, indicating the incorporation of environmental O into the tribological layer during sliding. This composite layer significantly improved the wear resistance by the synergistic plastic deformation mechanisms during sliding contact.","PeriodicalId":12442,"journal":{"name":"Friction","volume":"9 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2026-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148932862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cilia-inspired hydrogel surfaces for low-pressure lubrication via interfacial water structuring","authors":"Yixiao Wang,Peijia Li,Yilin Wang,Zhaoxiang Lu,Yun Feng,Ye Tian,Lei Jiang","doi":"10.26599/frict.2026.9441314","DOIUrl":"https://doi.org/10.26599/frict.2026.9441314","url":null,"abstract":"Abstract Lubrication plays a vital role in flexible electronics and medical devices, yet achieving stable low friction under low-pressure hydrodynamic conditions remains challenging. Existing approaches often lead to a coefficient of friction (COF) that increases with sliding velocity, due to the instability of interfacial water layers. Inspired by ocular surface structures, we developed a bio-inspired lubricating hydrogel (BLH) with nanowire arrays that confine interfacial water. This confined water remains stable under pressure, allowing COF to stay low and nearly independent of velocity. Under eyelid pressure (1.3-7.0 kPa), BLH achieved an ultra-low COF (0.0079-0.028), representing a 34-80% reduction compared to flat hydrogels (FH) and approaching that of natural corneal surfaces (0.014-0.037). The low friction was sustained over prolonged durations (≈ 6,000 s) and maintained at blinking-relevant speeds (≈ 4 cm/s). Tests using pig-eyeball rubbing and endoscope-probe models further demonstrated the robustness of this strategy, highlighting its promise for low-hysteresis coatings, flexible electronics, and medical devices.","PeriodicalId":12442,"journal":{"name":"Friction","volume":"387 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2026-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148932864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tribologically superior PTFE- and ATSP-based polymer composites for hydrogen environment applications","authors":"Ajinkya Raut,Emerson Escobar Nunez,Md Saifur Rahman,Andreas A. Polycarpou","doi":"10.26599/frict.2026.9441315","DOIUrl":"https://doi.org/10.26599/frict.2026.9441315","url":null,"abstract":"Abstract The global motivation for clean hydrogen energy has grown due to the need for additional sustainable energy sources. To address this demand, it is essential to minimize hydrogen loss during its production and transportation. Polymers are increasingly used to replace metals in components such as seals, valves, and gaskets. This transition is motivated by their superior tribological properties, corrosion resistance, and ability to operate without external lubrication. However, despite their excellent performance in air, these polymers have not been thoroughly tested in hydrogen environments. In this study, several polymer composites were developed using a vitrimer aromatic thermosetting copolyester (ATSP) and polytetrafluoroethylene (PTFE) matrices, and their tribological performance was evaluated in a specially designed tribometer under a 5% hydrogen atmosphere. Fluorine-rich transfer films were detected on the steel counterface, and the ATSP-matrix composite exhibited the lowest wear. These findings identify the materials studied as promising candidates for hydrogen-related tribological components. However, they should not be extrapolated directly to high-purity hydrogen, high pressure, elevated temperature, cyclic decompression, or long-duration service without additional validation.","PeriodicalId":12442,"journal":{"name":"Friction","volume":"62 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2026-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148932863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 cU-Net-based surrogate model for predicting rough surface contact parameters in line-contact friction","authors":"Yichun Xia,Hui Cao,Yonggang Meng","doi":"10.26599/frict.2026.9441313","DOIUrl":"https://doi.org/10.26599/frict.2026.9441313","url":null,"abstract":"Abstract Accurate and efficient prediction of contact parameters on rough surfaces is critical for the tribological design, condition monitoring, and failure analysis of line-contact components. Although physics-based models offer high prediction fidelity, their multi-field coupled iterative solvers are computationally expensive and complex, limiting practical engineering deployment. This work proposes a digital surrogate model based on the conditional U-Net (cU-Net) for predicting the spatial distributions of contact parameters, including contact temperature, pressure, and heat flux, on rough surfaces in line-contact friction. Real surface topographies are augmented via the Generative Patch Nearest-Neighbor (GPNN) model, and a wide-ranging training dataset is constructed through batch computation using a boundary lubrication physics-based model. The cU-Net incorporates an operating condition embedding mechanism to enable unified prediction across multiple operating conditions. Multi-scale spatial and channel attention modules are further integrated to enhance cross-scale feature extraction. A four-component progressive composite loss, assembled from established loss terms and tailored to the sparse extreme-value characteristics of rough surface contact parameters, is combined with Bayesian hyperparameter optimization and a three-stage progressive training strategy. On completely unseen rough surfaces the model achieves mean relative errors of 3.53%, 12.32%, and 13.66% for the temperature, pressure, and heat flux fields, respectively, with peak and top-5% errors that are lower still, and it is approximately 105 times faster than the physics-based model on the same workstation. Out-of-distribution tests quantify the degradation of accuracy under extrapolated operating conditions. Retraining with datasets generated from the corresponding physics-based models is expected to extend the framework to other lubrication regimes.","PeriodicalId":12442,"journal":{"name":"Friction","volume":"35 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2026-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148934104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reverse micelles as nanocarriers for polar friction modifiers in non-polar oils: AOT-mediated solubilization and boundary film formation","authors":"Haiyang Gu,Tomoko Hirayama,Lin Sun,Masako Yamada","doi":"10.26599/frict.2026.9441307","DOIUrl":"https://doi.org/10.26599/frict.2026.9441307","url":null,"abstract":"Abstract Polar organic friction modifiers can form effective boundary-lubrication films, but their limited compatibility with non-polar oils restricts their delivery to sliding interfaces. In this study, LCC was selected as a model polar additive to evaluate the ability of AOT reverse micelles in n-dodecane to act as nanocarriers for oil-incompatible friction modifiers. Increasing the water-to-surfactant molar ratio, w, expanded the transparent solubilization range of the model additive and increased the hydrodynamic size of the reverse micellar aggregates. Neutron reflectometry showed that hydrated AOT aggregates formed an adsorbed layer at the FeOx/oil interface, and incorporation of the model additive increased the fitted adsorbed-layer thickness from 3.05 to 3.43 nm under the same fixed-SLD fitting condition. Ball-on-disk tests showed lower friction after additive incorporation, and XPS detected chlorine-containing LCC-derived species on the worn surfaces, indicating that LCC was delivered to and retained at the sliding interface. Molecular dynamics simulations were used to observe the structural response of additive-loaded reverse micelles under high-pressure shear. These results support a reverse-micelle-assisted delivery mechanism in which hydrated AOT aggregates solubilize polar additives in the bulk oil, adsorb at the interface, and release additive-derived species under sliding.","PeriodicalId":12442,"journal":{"name":"Friction","volume":"30 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148894828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of pearl shell-inspired biomimetic textured rollers and their tribological performance during roller hemming","authors":"Xiyu Zhang,Liwu Miao,Ziqiang Zhang,Hongwei Zhao,Jianwei Sun,Juntao Guo,Changyi Liu,Tianye Yang","doi":"10.26599/frict.2026.9441311","DOIUrl":"https://doi.org/10.26599/frict.2026.9441311","url":null,"abstract":"Abstract The wear condition of the roller surface on the roll-forming end effector significantly affects the quality of automotive body molds and the service life of the corresponding equipment. To address these issues, this study proposes a biomimetic roller design strategy based on the microstructure of the pearl shell surface. A corresponding texture-morphology mapping model was established, followed by multi-scale mechanical and tribological performance analysis. Simulation results indicate that, under the same depth-to-width ratio conditions, the roller with arcuate grooves exhibits the lowest friction energy loss and the highest principal stress compared to rollers with vertical and rhombic grooves. Friction wear tests further validate the advantages of this structure, showing significantly lower coefficients of friction, wear depth, and wear mass than those of rollers with vertical and rhombic textures, demonstrating superior wear resistance. Based on this, the depth-to-width ratio structure of the arcuate striped roller was further optimized using the golden section method, determines a global optimal depth-to-width ratio of 0.775. Compared to ordinary rollers, the maximum principal stress along the rolling direction increased by 18.3% for the optimized roller, while rolling friction energy decreased by 70.28%. This study demonstrates that biomimetic textures can significantly improve the surface stress distribution and tribological performance of rollers, provide theoretical support and innovative solutions for enhancing the stability of automotive body manufacturing processes and the reliability of intelligent devices.","PeriodicalId":12442,"journal":{"name":"Friction","volume":"11 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148894804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Achieving macroscopic superlubricity on the steel surfaces with a functionally designed Ce‑based emulsion","authors":"Jinjin Li,Rui Zhang,Wen Zhong,Yun Chen,Yongqiang Xin,Yongfeng Yang","doi":"10.26599/frict.2026.9441310","DOIUrl":"https://doi.org/10.26599/frict.2026.9441310","url":null,"abstract":"Abstract This study explored the achievement of macroscopic liquid superlubricity using a Ce-based emulsion at the steel/steel interface. The Ce-based emulsion was prepared with Poly-L-lysine (PLL), oleic acid (OA), and a cerium-based emulsifier. After an initial running-in period of approximately 300 s, a superlubricity state characterized by a minimum coefficient of friction (COF) of 0.001 and a maximum contact pressure up to 197 MPa was achieved. The superlubricity originated from the synergistic adsorption of OA, PLL, and the emulsifier, driven by the C=C/COOH groups in OA, the amino-rich chains of PLL, and the Ce3+ containing head of the emulsifier. This cooperative adsorption promoted the formation of a hierarchical tribofilm that effectively separated the sliding surfaces under boundary lubrication. The study demonstrated the potential of emulsion-based lubricants for achieving ultra-low friction and wear in mechanical engineering applications.","PeriodicalId":12442,"journal":{"name":"Friction","volume":"12 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148894825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tribological performance of catalytic ceramic conversion treated Ti-15-3 β-Ti alloy under multi-lubrication conditions","authors":"Tong Pan,Diandian Wu,Ke Ren,Xiaoying Li,Kan Ma,Hanshan Dong","doi":"10.26599/frict.2026.9441312","DOIUrl":"https://doi.org/10.26599/frict.2026.9441312","url":null,"abstract":"Abstract The tribological behaviour of Ti-15-3 β-titanium alloy treated by integrating bulk treatment with surface functionalisation (IBTSF) was systematically investigated under unlubricated, oil-lubricated, deionised water and simulated seawater conditions. Reciprocating sliding tests were performed against a WC ball under loads of 10 N or 20 N for 10,000 cycles. The results demonstrate that the tribological performance strongly depends on both the IBTSF treatments and the test environments. Under unlubricated conditions, the catalytic ceramic conversion treatments (C3TAu32 and C3TAg32) exhibited significantly lower friction and wear than the conventional ceramic conversion treatment (C2T32), owing to the self-lubricating effect of Au/Ag and the formation of thicker oxide layers. Hence, under the most severe unlubricated sliding condition (20 N), C3TAu32 reduced the wear factor by 99% compared with C2T32. In contrast, C2T32 showed superior wear resistance in oil, deionised water and simulated seawater because of its dense oxide layer and strong oxide/substrate bonding, while C3TAg32 suffered from corrosive wear in simulated seawater. Thus, C2T32 exhibited a wear factor 90% lower than C3TAg32 under simulated seawater. These findings establish application-oriented guidelines for selecting IBTSF treatments under different service environments, with C3TAu32 recommended for unlubricated applications and C2T32 for oil-lubricated and marine environments. The possible wear mechanisms are discussed to advance scientific understanding.","PeriodicalId":12442,"journal":{"name":"Friction","volume":"6 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148894827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}