Carbon fiber-reinforced polymer (CFRP) composites were fabricated incorporating bio-derived calcium carbonate (CAC) and in-situ grown calcite-graphene hybrid fillers (CACG3, CACG6) to study their dry-sliding tribological performance. The CACG3/CFRP showed improved tribological performance, indicating reductions in the average COF of ∼6, 7.5, and 20 % compared to neat CFRP at applied loads of 10, 20, and 30 N, respectively. At 10 N, the specific wear rate (Ws) of CACG3/CFRP was ∼11.4 % lower than the CFRP composite. Atomic force microscopy revealed severe load-dependent surface degradation in CFRP, whereas CACG-filled composites maintained smoother and more stable wear tracks due to effective load bearing and lubrication. A detailed analysis of the worn surface using SEM, TEM, and XPS confirmed the formation of a compact tribofilm with calcite retention and enhanced graphitic ordering, thereby elucidating the underlying mechanisms of wear reduction. Experimental observations were supported by a finite element simulation of the wear process using the commercial tool ABAQUS.
{"title":"In-situ grown CACG-hybrid fillers for tribological optimization of carbon fiber-reinforced epoxy composites: Experimental and numerical insights","authors":"Chinmoy Kuila , Animesh Maji , Chandra Obulesu Bapanapalle , Abhinaba Chatterjee , Utpala Mukthipudi , Nilrudra Mandal , Rajkumar Wagmare , Naresh Chandra Murmu , Phani Kumar Mallisetty , Tapas Kuila","doi":"10.1016/j.triboint.2026.111686","DOIUrl":"10.1016/j.triboint.2026.111686","url":null,"abstract":"<div><div>Carbon fiber-reinforced polymer (CFRP) composites were fabricated incorporating bio-derived calcium carbonate (CAC) and in-situ grown calcite-graphene hybrid fillers (CACG3, CACG6) to study their dry-sliding tribological performance. The CACG3/CFRP showed improved tribological performance, indicating reductions in the average COF of ∼6, 7.5, and 20 % compared to neat CFRP at applied loads of 10, 20, and 30 N, respectively. At 10 N, the specific wear rate (W<sub>s</sub>) of CACG3/CFRP was ∼11.4 % lower than the CFRP composite. Atomic force microscopy revealed severe load-dependent surface degradation in CFRP, whereas CACG-filled composites maintained smoother and more stable wear tracks due to effective load bearing and lubrication. A detailed analysis of the worn surface using SEM, TEM, and XPS confirmed the formation of a compact tribofilm with calcite retention and enhanced graphitic ordering, thereby elucidating the underlying mechanisms of wear reduction. Experimental observations were supported by a finite element simulation of the wear process using the commercial tool ABAQUS.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"217 ","pages":"Article 111686"},"PeriodicalIF":6.1,"publicationDate":"2026-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145927774","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}
Pub Date : 2026-01-08DOI: 10.1016/j.triboint.2025.111613
Heng Liu , Deyuan Zhang , Daxi Geng
The nickel-based superalloy Inconel 718 is extensively utilized in applications demanding outstanding high-temperature properties, such as maintained strength, exceptional hardness, along with superior creep and corrosion resistance. Nevertheless, these very characteristics contribute to significant cutting forces and temperatures during machining, leading to accelerated tool wear and limiting productivity. While ultrasonic vibration-assisted cutting (UVAC) improves machinability, its application is largely confined to finishing operations due to efficiency constraints and amplitude suppression under high cutting loads. This study aims to comprehensively investigate the tool wear behaviors and underlying mechanisms in self-excited vibration cutting (SVC) of Inconel 718, a technique that spontaneously generates periodic vibration through process-structure coupling, offering advantages of structural simplicity, no need for external excitation, and resistance to amplitude suppression. A dedicated self-excited vibration turning holder (SVTH) was designed, and its vibration characteristics were meticulously characterized. Analysis revealed that the tool's kinematic trajectory approximates a counterclockwise-rotating flattened ellipse, primarily in the cutting speed and depth of cut directions. The scientific significance of this work lies in elucidating the primary wear reduction mechanism in SVC, which is the periodic separation and the significant reduction in the friction coefficient at the tool-workpiece interface, corroborated by cutting force reductions of up to 20 %. For the first time, the influence of self-excited vibration on tool wear is systematically examined under varying cutting parameters (cutting areas S=0.04, 0.06, and 0.09 mm²). Results demonstrate that SVC significantly prolongs tool life by approximately 238 %, 297 %, and 135 % at the respective cutting areas compared to conventional cutting (CC). Although adhesive wear remains the dominant mechanism for both CC and SVC tools, SVC substantially mitigates its severity. Furthermore, SVC tools exhibit a propensity for notch wear and crater wear, the manifestation of which is highly dependent on cutting parameters. This research provides fundamental insights into the wear mechanisms of SVC and establishes a scientific basis for enhancing machining efficiency and tool life in the processing of difficult-to-cut materials.
{"title":"Effects of self-excited vibration on tool wear behaviors in cutting of Inconel 718 superalloy","authors":"Heng Liu , Deyuan Zhang , Daxi Geng","doi":"10.1016/j.triboint.2025.111613","DOIUrl":"10.1016/j.triboint.2025.111613","url":null,"abstract":"<div><div>The nickel-based superalloy Inconel 718 is extensively utilized in applications demanding outstanding high-temperature properties, such as maintained strength, exceptional hardness, along with superior creep and corrosion resistance. Nevertheless, these very characteristics contribute to significant cutting forces and temperatures during machining, leading to accelerated tool wear and limiting productivity. While ultrasonic vibration-assisted cutting (UVAC) improves machinability, its application is largely confined to finishing operations due to efficiency constraints and amplitude suppression under high cutting loads. This study aims to comprehensively investigate the tool wear behaviors and underlying mechanisms in self-excited vibration cutting (SVC) of Inconel 718, a technique that spontaneously generates periodic vibration through process-structure coupling, offering advantages of structural simplicity, no need for external excitation, and resistance to amplitude suppression. A dedicated self-excited vibration turning holder (SVTH) was designed, and its vibration characteristics were meticulously characterized. Analysis revealed that the tool's kinematic trajectory approximates a counterclockwise-rotating flattened ellipse, primarily in the cutting speed and depth of cut directions. The scientific significance of this work lies in elucidating the primary wear reduction mechanism in SVC, which is the periodic separation and the significant reduction in the friction coefficient at the tool-workpiece interface, corroborated by cutting force reductions of up to 20 %. For the first time, the influence of self-excited vibration on tool wear is systematically examined under varying cutting parameters (cutting areas S=0.04, 0.06, and 0.09 mm²). Results demonstrate that SVC significantly prolongs tool life by approximately 238 %, 297 %, and 135 % at the respective cutting areas compared to conventional cutting (CC). Although adhesive wear remains the dominant mechanism for both CC and SVC tools, SVC substantially mitigates its severity. Furthermore, SVC tools exhibit a propensity for notch wear and crater wear, the manifestation of which is highly dependent on cutting parameters. This research provides fundamental insights into the wear mechanisms of SVC and establishes a scientific basis for enhancing machining efficiency and tool life in the processing of difficult-to-cut materials.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"217 ","pages":"Article 111613"},"PeriodicalIF":6.1,"publicationDate":"2026-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979104","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}
Pub Date : 2026-01-07DOI: 10.1016/j.triboint.2026.111682
Penghui Xu , Pu Li , Qinghua Zhou , Xiaowu Luo , Lin Yang , Chaowen Deng , Yanmin Liu , Qiang Zhang
This study explores the dynamic self-healing of sliding wear in slip rings using liquid metal (LM). Molecular dynamics (MD) simulations were employed to systematically investigate the effects of scratch depth and sliding velocity on the repair performance of Ga coatings. The deformation behavior of the Cu–Ag alloy substrate during scratching is also analyzed at the atomic scale. The results reveal that the friction force increases approximately linearly with scratch depth, whereas the average coefficient of friction stabilizes once the indenter contacts the substrate surface. The Ga coating exhibits a self-healing effect against scratching, and the repairing rate increases as the scratch velocity is augmented. However, local solidification limits complete repair. Remarkably, the accumulation morphology of Ga, projected onto the X–Y plane and the distribution of regions exceeding its melting point, forms a ring-like structure, with the outer diameter exhibiting a near-linear correlation with scratch depth. Moreover, there are two velocity thresholds, at which both the Ga pile-up height and the dislocation density in the substrate reach their maxima. These findings provide comprehensive microscopic insights into the nano-scratch mechanisms of Cu–Ag alloys and underscore the potential of LM for high-performance, self-repairing surfaces.
{"title":"Dynamic self-healing of liquid metal in Cu–Ag alloy nano-scratch with molecular dynamics and experimental study","authors":"Penghui Xu , Pu Li , Qinghua Zhou , Xiaowu Luo , Lin Yang , Chaowen Deng , Yanmin Liu , Qiang Zhang","doi":"10.1016/j.triboint.2026.111682","DOIUrl":"10.1016/j.triboint.2026.111682","url":null,"abstract":"<div><div>This study explores the dynamic self-healing of sliding wear in slip rings using liquid metal (LM). Molecular dynamics (MD) simulations were employed to systematically investigate the effects of scratch depth and sliding velocity on the repair performance of Ga coatings. The deformation behavior of the Cu–Ag alloy substrate during scratching is also analyzed at the atomic scale. The results reveal that the friction force increases approximately linearly with scratch depth, whereas the average coefficient of friction stabilizes once the indenter contacts the substrate surface. The Ga coating exhibits a self-healing effect against scratching, and the repairing rate increases as the scratch velocity is augmented. However, local solidification limits complete repair. Remarkably, the accumulation morphology of Ga, projected onto the X–Y plane and the distribution of regions exceeding its melting point, forms a ring-like structure, with the outer diameter exhibiting a near-linear correlation with scratch depth. Moreover, there are two velocity thresholds, at which both the Ga pile-up height and the dislocation density in the substrate reach their maxima. These findings provide comprehensive microscopic insights into the nano-scratch mechanisms of Cu–Ag alloys and underscore the potential of LM for high-performance, self-repairing surfaces.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"217 ","pages":"Article 111682"},"PeriodicalIF":6.1,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979107","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}
Pub Date : 2026-01-07DOI: 10.1016/j.triboint.2025.111652
Xinmin Zhu , Wenbin Zheng , Bingqing Liu , Yang Liu , Shitong Jiang , Shuaijun Zhang , Shiyuan Pei
Modeling hydrodynamic lubrication with concurrent surface texture and roughness remains a multiscale challenge, as their coupled effects cannot be captured by existing homogenization approaches that account for only one microscale (texture or roughness), nor affordably resolved by direct numerical simulation (DNS). This work introduces a generalized reiterated homogenization method (GRHM) that unifies macroscopic geometry, texture, and roughness into a single three-scale framework. A two-tiered validation — against classical homogenization and DNS — confirms algorithmic correctness and high predictive fidelity in pressure, load-carrying capacity, and friction force. GRHM captures directional coupling and geometric nonlinearity while maintaining scale-independent computational cost, establishing a verified framework for multiscale lubrication analysis and surface design.
{"title":"Generalized reiterated homogenization method for multiscale modeling of surface texture and roughness in hydrodynamic lubrication","authors":"Xinmin Zhu , Wenbin Zheng , Bingqing Liu , Yang Liu , Shitong Jiang , Shuaijun Zhang , Shiyuan Pei","doi":"10.1016/j.triboint.2025.111652","DOIUrl":"10.1016/j.triboint.2025.111652","url":null,"abstract":"<div><div>Modeling hydrodynamic lubrication with concurrent surface texture and roughness remains a multiscale challenge, as their coupled effects cannot be captured by existing homogenization approaches that account for only one microscale (texture or roughness), nor affordably resolved by direct numerical simulation (DNS). This work introduces a generalized reiterated homogenization method (GRHM) that unifies macroscopic geometry, texture, and roughness into a single three-scale framework. A two-tiered validation — against classical homogenization and DNS — confirms algorithmic correctness and high predictive fidelity in pressure, load-carrying capacity, and friction force. GRHM captures directional coupling and geometric nonlinearity while maintaining scale-independent computational cost, establishing a verified framework for multiscale lubrication analysis and surface design.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"217 ","pages":"Article 111652"},"PeriodicalIF":6.1,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145927769","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}
Pub Date : 2026-01-07DOI: 10.1016/j.triboint.2026.111683
Chao Jia , Chengxiong Liu , Ligang Yao , Yanming Mu , Zongde Fang
Under high-speed and heavy-load conditions, the lubrication performance of asymmetric helical face gears has a crucial impact on the reliability of the transmission system. For asymmetric gears, an important issue to note is that while increasing the pressure angle helps reduce the curvature of the meshing contact point and thus improves lubrication load capacity, it also leads to a decrease in the contact ratio, thereby increasing the load density of a single tooth and reducing lubrication performance. Therefore, to systematically evaluate the influence of pressure angle on the lubrication characteristics of asymmetric helical face gears, a mathematical model combining loaded tooth contact analysis (LTCA) and thermal-elastohydrodynamic lubrication (TEHL) is established in this paper. A numerical example is given, and the pressure distribution, temperature distribution, and film thickness distribution on the tooth surface of the mesh-in area, mesh-mid area and mesh-out area are calculated under a pressure angle of 30°/20°. Calculation results show that the worst lubrication conditions are found in the meshing-in area. Furthermore, the maximum contact temperature and minimum oil film thickness along the meshing line are calculated and compared for four cases with pressure angles of 20°/20°, 25°/20°, 30°/20°, and 35°/20°. The comparison results show that increasing the pressure angle can improve the lubrication in the meshing-in and meshing-out areas, but it will worsen the lubrication of the middle area of the tooth surface.
{"title":"An investigation on the lubrication characteristics of asymmetric helical face gear drives: An emphasis on balance between pressure angle and contact ratio","authors":"Chao Jia , Chengxiong Liu , Ligang Yao , Yanming Mu , Zongde Fang","doi":"10.1016/j.triboint.2026.111683","DOIUrl":"10.1016/j.triboint.2026.111683","url":null,"abstract":"<div><div>Under high-speed and heavy-load conditions, the lubrication performance of asymmetric helical face gears has a crucial impact on the reliability of the transmission system. For asymmetric gears, an important issue to note is that while increasing the pressure angle helps reduce the curvature of the meshing contact point and thus improves lubrication load capacity, it also leads to a decrease in the contact ratio, thereby increasing the load density of a single tooth and reducing lubrication performance. Therefore, to systematically evaluate the influence of pressure angle on the lubrication characteristics of asymmetric helical face gears, a mathematical model combining loaded tooth contact analysis (LTCA) and thermal-elastohydrodynamic lubrication (TEHL) is established in this paper. A numerical example is given, and the pressure distribution, temperature distribution, and film thickness distribution on the tooth surface of the mesh-in area, mesh-mid area and mesh-out area are calculated under a pressure angle of 30°/20°. Calculation results show that the worst lubrication conditions are found in the meshing-in area. Furthermore, the maximum contact temperature and minimum oil film thickness along the meshing line are calculated and compared for four cases with pressure angles of 20°/20°, 25°/20°, 30°/20°, and 35°/20°. The comparison results show that increasing the pressure angle can improve the lubrication in the meshing-in and meshing-out areas, but it will worsen the lubrication of the middle area of the tooth surface.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"217 ","pages":"Article 111683"},"PeriodicalIF":6.1,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145927766","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}
Pub Date : 2026-01-07DOI: 10.1016/j.triboint.2026.111680
Wentao Liu , Wuji Zhang , Zehua Hu , Jinyuan Tang , Yuansheng Zhou , Feng Yin , Zhenyu Zhou , Zhiwei Wang
To address the complex frictional environment of face gear transmissions—characterized by high contact stress, wear, and scuffing risks under boundary or mixed lubrication—surface micro-textures are introduced to enhance lubrication and tribological performance. A transient mixed thermo-elastohydrodynamic lubrication (transient MTEHL) model is innovatively proposed, integrating surface micro-texture distribution during instantaneous meshing to resolve synergistic effects with transient meshing. The model is solved using efficient numerical methods (semi-system method, GC-FFT, and PMD method) and validated against existing literature, confirming the reliability of its solutions. Surface micro-textures significantly enhance lubrication performance through improved oil storage and hydrodynamic effects, drastically reducing the dry contact area and suppressing critical temperature peaks. Comprehensive parametric studies on micro-textures depth, angle, shape, and density reveal a critical tribological trade-off: analysis indicates that the geometric configuration maximizing oil film thickness does not necessarily achieve the minimum friction coefficient or optimal temperature control. Furthermore, the benefits of micro-textures are strictly conditional—improper micro-textures distribution may induce severe local fluid shear hotspots and pressure concentrations under different surface conditions, necessitating precise optimization design tailored to specific surface conditions.
{"title":"Transient mixed thermo-elastohydrodynamic lubrication of surface micro-textured face gear pair","authors":"Wentao Liu , Wuji Zhang , Zehua Hu , Jinyuan Tang , Yuansheng Zhou , Feng Yin , Zhenyu Zhou , Zhiwei Wang","doi":"10.1016/j.triboint.2026.111680","DOIUrl":"10.1016/j.triboint.2026.111680","url":null,"abstract":"<div><div>To address the complex frictional environment of face gear transmissions—characterized by high contact stress, wear, and scuffing risks under boundary or mixed lubrication—surface micro-textures are introduced to enhance lubrication and tribological performance. A transient mixed thermo-elastohydrodynamic lubrication (transient MTEHL) model is innovatively proposed, integrating surface micro-texture distribution during instantaneous meshing to resolve synergistic effects with transient meshing. The model is solved using efficient numerical methods (semi-system method, GC-FFT, and PMD method) and validated against existing literature, confirming the reliability of its solutions. Surface micro-textures significantly enhance lubrication performance through improved oil storage and hydrodynamic effects, drastically reducing the dry contact area and suppressing critical temperature peaks. Comprehensive parametric studies on micro-textures depth, angle, shape, and density reveal a critical tribological trade-off: analysis indicates that the geometric configuration maximizing oil film thickness does not necessarily achieve the minimum friction coefficient or optimal temperature control. Furthermore, the benefits of micro-textures are strictly conditional—improper micro-textures distribution may induce severe local fluid shear hotspots and pressure concentrations under different surface conditions, necessitating precise optimization design tailored to specific surface conditions.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"217 ","pages":"Article 111680"},"PeriodicalIF":6.1,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979142","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}
Pub Date : 2026-01-07DOI: 10.1016/j.triboint.2026.111684
Ziheng Wang , Qian Qi , Lujie Wang , Xiquan Zhang , Xiaoqi Yang , Kangping Sun
The in-situ formation of tribo-oxide layer rich in oxides lubricants is one effective method to simultaneously achieve self-lubricating and wear resistance of materials. In this study, the TaC/Hastelloy composites with different TaC contents (70–85 wt%) were fabricated by in-situ reactive sintering technique. With the increase of TaC content, the hardness of composite increases from 866 HV to 1244 HV, due to the dispersion strengthening and fine grain strengthening of TaC particles. The oxidation resistance of composites at 600 ℃ is reduced, resulted from the more content of Ta oxides with high PBR to induce cracks in oxide scale. The TaC/Hastelloy composite present excellent self-lubricating property (COF: 0.22–0.31) by generating in-situ tribo-oxide layer rich in MoO3, Ta2O5 and NiO. Notably, the oxides lubricants are same to the phase composition of oxide scale on composites oxidized at 600 ℃, indicating the generation of oxides lubricants by frictional heat at room temperature. One dense and continuous tribo-oxide layer is fast formed on the worn surface of 85TaC, because of the synergistic effect of highest hardness and oxidation rate. The oxidation reaction quickly occurs during the frictional process, and the high hardness improves the load bearing capacity of tribo-oxide layer. The wear mechanism of 70TaC is dominated by abrasive wear, oxidation wear and delamination wear, while the primary wear mechanism of 85TaC is oxidation wear. As a result, 85TaC presents lowest COF (0.22) and wear rate (2.91 × 10−6 mm³/N·m), 29 % and 78 % lower than those (0.31 and 12.96 × 10−6 mm³/N·m) of 70TaC.
{"title":"One novel self-lubricating TaC/hastelloy composite through in-situ formation of tribo-oxide layer rich in oxides lubricants","authors":"Ziheng Wang , Qian Qi , Lujie Wang , Xiquan Zhang , Xiaoqi Yang , Kangping Sun","doi":"10.1016/j.triboint.2026.111684","DOIUrl":"10.1016/j.triboint.2026.111684","url":null,"abstract":"<div><div>The in-situ formation of tribo-oxide layer rich in oxides lubricants is one effective method to simultaneously achieve self-lubricating and wear resistance of materials. In this study, the TaC/Hastelloy composites with different TaC contents (70–85 wt%) were fabricated by in-situ reactive sintering technique. With the increase of TaC content, the hardness of composite increases from 866 HV to 1244 HV, due to the dispersion strengthening and fine grain strengthening of TaC particles. The oxidation resistance of composites at 600 ℃ is reduced, resulted from the more content of Ta oxides with high PBR to induce cracks in oxide scale. The TaC/Hastelloy composite present excellent self-lubricating property (COF: 0.22–0.31) by generating in-situ tribo-oxide layer rich in MoO<sub>3</sub>, Ta<sub>2</sub>O<sub>5</sub> and NiO. Notably, the oxides lubricants are same to the phase composition of oxide scale on composites oxidized at 600 ℃, indicating the generation of oxides lubricants by frictional heat at room temperature. One dense and continuous tribo-oxide layer is fast formed on the worn surface of 85TaC, because of the synergistic effect of highest hardness and oxidation rate. The oxidation reaction quickly occurs during the frictional process, and the high hardness improves the load bearing capacity of tribo-oxide layer. The wear mechanism of 70TaC is dominated by abrasive wear, oxidation wear and delamination wear, while the primary wear mechanism of 85TaC is oxidation wear. As a result, 85TaC presents lowest COF (0.22) and wear rate (2.91 × 10<sup>−6</sup> mm³/N·m), 29 % and 78 % lower than those (0.31 and 12.96 × 10<sup>−6</sup> mm³/N·m) of 70TaC.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"217 ","pages":"Article 111684"},"PeriodicalIF":6.1,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145927763","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}
Pub Date : 2026-01-07DOI: 10.1016/j.triboint.2026.111681
Fangyan Luo , Hongtao Jin , Junbiao Zheng , Wenqing Shi , Jiang Huang
A series of CoCrFeNiMn-x wt% Nb₂AlC (x = 0, 15, 30, 45) coatings were successfully fabricated via laser cladding. Performance tests show that when x = 45, the coating exhibits ultra-high wear resistance under both room temperature (RT) and high temperature (HT) conditions: its RT wear rate is as low as 5.23 × 10−6 mm3/(N·m), while the HT wear rate is further optimized to 2.6 × 10−7 mm3/(N·m). Systematic microstructure analysis reveals that the enhanced wear resistance originates from two synergistic mechanisms. Firstly, Nb2AlC strengthens the coating by regulating its microstructure: it promotes in-situ formation of NbC and Laves phases, which enhance matrix strength via second-phase, grain refinement and dislocation strengthening; meanwhile, Al in Nb2AlC dissolves into the FCC phase, optimizing its mechanical properties through solid solution strengthening and lattice distortion. Secondly, the two hard phases regulate oxide film growth during wear, ensuring its formation rate exceeds consumption, thus constructing a continuous, effective wear-resistant protective layer. This study reveals the multi-mechanism synergistic strengthening mechanism, providing a new technical path for improving HEA coating wear resistance and laying a theoretical and experimental foundation for high-performance HEA coating preparation and engineering application.
{"title":"Laser-cladded CoCrFeNiMn-Nb2AlC HEA coatings: Microstructure-oxide film synergy for ultra-high room/high-temperature wear resistance","authors":"Fangyan Luo , Hongtao Jin , Junbiao Zheng , Wenqing Shi , Jiang Huang","doi":"10.1016/j.triboint.2026.111681","DOIUrl":"10.1016/j.triboint.2026.111681","url":null,"abstract":"<div><div>A series of CoCrFeNiMn-x wt% Nb₂AlC (x = 0, 15, 30, 45) coatings were successfully fabricated via laser cladding. Performance tests show that when x = 45, the coating exhibits ultra-high wear resistance under both room temperature (RT) and high temperature (HT) conditions: its RT wear rate is as low as 5.23 × 10<sup>−6</sup> mm<sup>3</sup>/(N·m), while the HT wear rate is further optimized to 2.6 × 10<sup>−7</sup> mm<sup>3</sup>/(N·m). Systematic microstructure analysis reveals that the enhanced wear resistance originates from two synergistic mechanisms. Firstly, Nb<sub>2</sub>AlC strengthens the coating by regulating its microstructure: it promotes in-situ formation of NbC and Laves phases, which enhance matrix strength via second-phase, grain refinement and dislocation strengthening; meanwhile, Al in Nb<sub>2</sub>AlC dissolves into the FCC phase, optimizing its mechanical properties through solid solution strengthening and lattice distortion. Secondly, the two hard phases regulate oxide film growth during wear, ensuring its formation rate exceeds consumption, thus constructing a continuous, effective wear-resistant protective layer. This study reveals the multi-mechanism synergistic strengthening mechanism, providing a new technical path for improving HEA coating wear resistance and laying a theoretical and experimental foundation for high-performance HEA coating preparation and engineering application.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"217 ","pages":"Article 111681"},"PeriodicalIF":6.1,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145928450","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}
Pub Date : 2026-01-06DOI: 10.1016/j.triboint.2026.111664
Yibin Liu , Konghua Yang , Hongtao Huang , Li Bao , Jingran Wang , Yuchao Luo , Chunbao Liu
The operational environments of rotor systems are intricate, influenced by factors such as high-frequency vibrations and alternating loads, leading to frequent faults. Thus, rotor status monitoring is crucial yet remains challenging. In this work, we propose a novel misalignment identification triboelectric sensor (MITS), engineered for the simultaneous real-time rotor speed monitoring, misalignment direction identification, and fault severity assessment. An external encapsulation structure is designed considering operational reliability, and the output performance and robustness of MITS under various working conditions are investigated. Utilizing the developed rotor speed in-situ monitoring system, MITS enables high-precision real-time speed tracking, achieving a measurement error rate below 0.48 % across a range of 10–2996 rpm. Subsequently, the correlation mechanism between the signal distribution from multiple independent measurement points of MITS and misalignment faults is revealed, and a quantitative analytical model for rotor misalignment faults is established, achieving one-to-one identification of misalignment direction and severity. Under preset distinct fault scenarios, the directional error is less than ±0.77° and the fault severity diagnosis accuracy exceeding 96.44 %. Furthermore, the diagnostic performance of MITS is compared with that of commercial vibration sensors using deep learning algorithms. The findings demonstrate that the MITS-based approach achieves a diagnostic accuracy exceeding 98.60 %, significantly outperforming conventional vibration-based methods. This further validates the feasibility of the MITS-based fault identification strategy.
{"title":"Dynamic contact domain-based triboelectric sensors for rotor status intelligent perception","authors":"Yibin Liu , Konghua Yang , Hongtao Huang , Li Bao , Jingran Wang , Yuchao Luo , Chunbao Liu","doi":"10.1016/j.triboint.2026.111664","DOIUrl":"10.1016/j.triboint.2026.111664","url":null,"abstract":"<div><div>The operational environments of rotor systems are intricate, influenced by factors such as high-frequency vibrations and alternating loads, leading to frequent faults. Thus, rotor status monitoring is crucial yet remains challenging. In this work, we propose a novel misalignment identification triboelectric sensor (MITS), engineered for the simultaneous real-time rotor speed monitoring, misalignment direction identification, and fault severity assessment. An external encapsulation structure is designed considering operational reliability, and the output performance and robustness of MITS under various working conditions are investigated. Utilizing the developed rotor speed in-situ monitoring system, MITS enables high-precision real-time speed tracking, achieving a measurement error rate below 0.48 % across a range of 10–2996 rpm. Subsequently, the correlation mechanism between the signal distribution from multiple independent measurement points of MITS and misalignment faults is revealed, and a quantitative analytical model for rotor misalignment faults is established, achieving one-to-one identification of misalignment direction and severity. Under preset distinct fault scenarios, the directional error is less than ±0.77° and the fault severity diagnosis accuracy exceeding 96.44 %. Furthermore, the diagnostic performance of MITS is compared with that of commercial vibration sensors using deep learning algorithms. The findings demonstrate that the MITS-based approach achieves a diagnostic accuracy exceeding 98.60 %, significantly outperforming conventional vibration-based methods. This further validates the feasibility of the MITS-based fault identification strategy.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"217 ","pages":"Article 111664"},"PeriodicalIF":6.1,"publicationDate":"2026-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145927771","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}
Pub Date : 2026-01-06DOI: 10.1016/j.triboint.2025.111651
Junbin Lai , Peng Dong , Huijun Yue
Gear wear is an inevitable form of damage during long-term operation. However, current research on gear wear prediction primarily relies on quasi-static conditions, which neglects the reciprocal influence of dynamic tooth loads and friction. To address this gap, a dynamic wear evolution model is proposed by integrating sub-models of tooth-loaded contact, gear thermal-elastohydrodynamic lubrication (TEHL), modified gear wear, and gear tribo-dynamic effects. This model not only enables accurate prediction of tooth flank wear evolution but also captures the reciprocal effect of dynamic tooth loads and tribological behavior. The results indicate that gear wear predicted by the dynamic model is more severe than that by the static model. As transmitted load and operating speed increase, this discrepancy becomes more pronounced. This phenomenon is attributed to the decrease in time-varying mesh stiffness and the increase in loaded static transmission error excitation as gear wear accumulates, which in turn leads to higher dynamic tooth loads and friction forces. Additionally, gear wear further exacerbates the system dynamic response. As wear accumulates, the gear pair tends to enter chaotic motion more readily, manifested in phenomena such as tooth contact separation or back contact. These behaviors induce violent vibrations and a significant reduction in the transmission stability of the gear pair.
{"title":"Dynamic wear evolution analysis of spur gear considering tribo-dynamic effect","authors":"Junbin Lai , Peng Dong , Huijun Yue","doi":"10.1016/j.triboint.2025.111651","DOIUrl":"10.1016/j.triboint.2025.111651","url":null,"abstract":"<div><div>Gear wear is an inevitable form of damage during long-term operation. However, current research on gear wear prediction primarily relies on quasi-static conditions, which neglects the reciprocal influence of dynamic tooth loads and friction. To address this gap, a dynamic wear evolution model is proposed by integrating sub-models of tooth-loaded contact, gear thermal-elastohydrodynamic lubrication (TEHL), modified gear wear, and gear tribo-dynamic effects. This model not only enables accurate prediction of tooth flank wear evolution but also captures the reciprocal effect of dynamic tooth loads and tribological behavior. The results indicate that gear wear predicted by the dynamic model is more severe than that by the static model. As transmitted load and operating speed increase, this discrepancy becomes more pronounced. This phenomenon is attributed to the decrease in time-varying mesh stiffness and the increase in loaded static transmission error excitation as gear wear accumulates, which in turn leads to higher dynamic tooth loads and friction forces. Additionally, gear wear further exacerbates the system dynamic response. As wear accumulates, the gear pair tends to enter chaotic motion more readily, manifested in phenomena such as tooth contact separation or back contact. These behaviors induce violent vibrations and a significant reduction in the transmission stability of the gear pair.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"217 ","pages":"Article 111651"},"PeriodicalIF":6.1,"publicationDate":"2026-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145928452","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}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号